FLOOD INSURANCE STUDY

FLOOD INSURANCE STUDY A Report of Flood Hazards in DUPAGE COUNTY, ILLINOIS DuPage County Community Name Community Number River Basin Community Name Community Number River Basin Addison, Village of 7098 Lemont, Village of 707 Aurora, City of 70320 Lisle, Village of 702 Bartlett, Village of 70059 Lombard, Village of 7022 Bensenville, Village of 70200 Naperville, City of 7023 Bloomingdale, Village of 7020 Oak Brook, Village of 7024 Carol Stream, Village of 70202 Oakbrook Terrace, City of 7025 Clarendon Hills, Village of 70203 Roselle, Village of 7026 Darien, City of 70750 Villa Park, Village of 7027 Downers Grove, Village of 70204 Warrenville, City of 7028 DuPage County (Unincorporated Areas) 7097 Elmhurst, City of 70205 Glen Ellyn, Village of 70207 Glendale Heights, Village of 70206 Hinsdale, Village of 7005 Itasca, Village of 7020 Wayne, Village of 70865 West Chicago, City of 7029 Westmont, Village of 70220 Wheaton, City of 7022 Willowbrook, Village of 70222 Winfield, Village of 70223 Wood Dale, City of 70224 Woodbridge, Village of 70737 Federal Emergency Management Agency State of Illinois Flood Insurance Study Number 7043CV000H

FOREwORD This countywide Flood Insurance Study (FIS) Report was produced through a unique cooperative partnership between the DuPage County and the Federal Emergency Management Agency (FEMA). DuPage County has implemented a long-term approach to floodplain management to decrease the costs associated with flooding. As a part of this effort, DuPage County has joined with FEMA in a Cooperating Technical Partner (CTP) agreement to produce and maintain this FIS Report and the accompanying digital Flood Insurance Rate Map (FIRM) for DuPage County.

NOTICE TO FLOOD INSURANCE STUDY USERS Communities participating in the National Flood Insurance Program have established repositories of flood hazard data for floodplain management and flood insurance purposes. This Flood Insurance Study (FIS) may not contain all data available within the repository. It is advisable to contact the community repository for any additional data. Part or all of this FIS may be revised and republished at any time. In addition, part of this FIS may be revised by the Letter of Map Revision process, which does not involve republication or redistribution of the FIS. It is, therefore, the responsibility of the user to consult with community officials and to check the community repository to obtain the most current FIS components. Initial Countywide FIS Effective Date: Revised Countywide FIS Date:

TABLE OF CONTENTS Page.0 INTRODUCTION. Purpose of Study.2 Authority and Acknowledgments.3 Coordination 6 2.0 AREA STUDIED 7 2. Scope of Study 7 2.2 Community Description 8 2.3 Principal Flood Problems 9 2.4 Flood Protection Measures 2 3.0 ENGINEERING METHODS 29 3. Hydrologic Analyses 29 3.2 Hydraulic Analyses 52 3.3 Vertical Datum 68 4.0 FLOODPLAIN MANAGEMENT APPLICATIONS 68 4. Floodplain Boundaries 69 4.2 Floodways 70 5.0 INSURANCE APPLICATIONS 8 6.0 FLOOD INSURANCE RATE MAP 82 7.0 OTHER STUDIES 83 8.0 LOCATION OF DATA 86 9.0 BIBLIOGRAPHY AND REFERENCES 86 ii

TABLE OF CONTENTS - continued Page FIGURES Figure - Floodway Schematic 63 TABLES Table - Initial and Final CCO Meetings 6-7 Table 2 - Flooding Sources Studied by Detailed Methods 7-8 Table 3 - Summary of Discharges 2-27 Table 4 Manning s n Values 32-33 Table 5 - Floodway Data 37-62 Table 6 00-Year Flood Data Table No reference made in text for this table! Table 7 - Community Map History 66-68 EXHIBITS Exhibit - Flood Profiles Addison Creek (DPAC) Panel 0P Addison Creek Tributary No. (DPAC) Panel 02P Addison Creek Tributary No. 2 (DPAC) Panel 03P Addison Creek Tributary No. 3 (DPAC) Panels 04P-05P Armitage Ditch (EBAR) Panels 30P-3P Armitage Fork (EBAR) Panel 32P Bensenville Ditch (DPBP) Panels 06P-07P Brewster Creek (FRBC) Panels 85P-86P Briarwood Ditch (SCGC) Panel 98P Bronswood Cemetary Tributary (SCBW) Panels 9P-93P Crabtree Creek (EBCR) Panels 33P-35P Cress Creek (WBCC) Panel 50P Des Plaines River (DPDP) Panels 08P-09P Devon Avenue Tributary (SCDA) Panel 94P East Branch Du Page River (EBEB) Panels 36P-43P East Branch Sawmill Creek (SWSW) Panels 44P-45P East Branch Tributary No. (EBE) Panels 44P-45P East Branch Tributary No. 2 (EBE2) Panel 46P East Branch Tributary No. 3 (EBEB) Panels 47P-48P East Branch Tributary No. 4 (EBGL) Panels 49P-50P East Branch Tributary No. 5 (EBWI) Panels 5P-53P St. Procopius Creek (EBE6) Panels 54P-55P iii

TABLE OF CONTENTS - continued EXHIBITS continued Exhibit - Flood Profiles (continued) East Branch Tributary No. 7 (EBE7) Panels 56P-57P Ferry Creek (WBFE) Panels 5P-54P Ferry Creek Tributary No. (WBFE) Panels 55P-57P Flagg Creek (DPFC) Panel 2P Ginger Creek (SCGC) Panels 95P-97P Heritage Oaks Tributary (SCGC) Panel 99P Klein Creek Tributary No. (WBKC) Panels 67P-68P Klein Creek Tributary No. 2 (WBKC) Panel 69P Klein Creek Tributary No. 3 (WBKC) Panel 70P Klein Creek (WBKC) Panels 6P-66P Kress Creek (WBKR) Panels 7P-77P Lacey Creek (EBLA) Panels 58P-60P Lombard Tributary (SCGC) Panel 00P Mays Lake Tributary (SCGC) Panels 0P-02P Meacham Creek (SCSB) Panels 4P-5P Midwest Club Tributary (SCGC) Panel 03P North Branch St. Joseph Creek (EBSJ) Panel 80P Norton Creek (FRNC) Panel 87P Norton Creek Tributary (FRNC) Panel 88P North Unnamed Creek (DPWL) Panel 24P Plainfield Road Ditch (DPFC) Panels 7P-8P Prentiss Creek (EBPR) Panels 6P-64P Rott Creek (EBRC) Panels 65P-68P Salt Creek (SCSC) Panels 6P-30P Sawmill Creek (SWSW) Panels 36P-40P Sawmill Creek Tributary No. (SWSW) Panels 48P-49P Sawmill Creek Tributary No. 3 (DPDP) Panels 0P-5P South Branch St. Joseph Creek (EBSJ) Panels 8P-82P South Fork Westwood Creek (SCWC) Panel 35P South Unnamed Creek (DPWL) Panel 23P Spring Brook Creek (SCSB) Panels 06P-2P Spring Brook No. (WBSP) Panels 80P-84P Spring Brook No. 2 (DUSG) Panels 25P-29P Spring Road Tributary (SCOB) Panels 04P-05P St. Joseph Creek (EBSJ) Panels 69P-75P St. Joseph Creek Tributary (EBSJ) Panel 83P Sugar Creek (SCSU) Panels 3P-32P Sugar Creek Tributary A (SCSU) Panel 33P Tributary (A) (EBSJ) Panels 76P-78P Tributary 2(B) (EBSJ) Panel 79P Unnamed Creek (South of Foxcroft Road) (WBFX) Panels 58P-59P Unnamed Stream (North of 22 nd Street) (EBTS) Panel 84P Unnamed Creek (South of 87 th Street) (WBFX) Panel 60P Unnamed Tributary to Kress Creek (WBKR) Panels 78P-79P Wards Creek (SWSW) Panels 46P-47P Waubansee Creek (FRWA) Panels 89P-90P iv

TABLE OF CONTENTS - continued EXHIBITS continued Exhibit - Flood Profiles (continued) West Branch DuPage River (WBWB) Panels 85P-96P West Branch Sawmill Creek (SWSW) Panels 4P-43P West Branch Tributary No. (WBW) Panels 97P-98P West Branch Tributary No. 2 (Country Creek) (WBW2) Panels 99P-200P West Branch Tributary No. 3 (WBW3) Panels 20P-202P West Branch Tributary No. 4 (WBW4) Panels 203P-204P West Branch Tributary No. 5 (WBW5) Panel 205P West Branch Tributary No. 6 (WBW6) Panels 206P-208P West Branch Tributary No. 7 (WBW7) Panels 209P-2P West Branch Tributary to Spring Brook Creek (SCSB) Panel 3P Westwood Creek (SCWC) Panel 34P Winfield Creek (WBWF) Panels 22P-27P Winding Creek (WBWG) Panels 28P-29P 59 th Street Ditch (DPFC) Panel 22P 63 rd Street Ditch (DPFC) Panels 9P-20P 79 th Street Ditch (DPFC) Panel 6P Exhibit 2 - Flood Insurance Rate Map Index Flood Insurance Rate Map v

FLOOD INSURANCE STUDY LINOIS.0 INTRODUCTION. Purpose of Study This countywide Flood Insurance Study (FIS) investigates the existence and severity of flood hazards in, or revises and updates previous FISs/Flood Insurance Rate Maps (FIRMs) for the geographic area of DuPage County, Illinois, including: the Villages of Addison, Bartlett, Bensenville, Bloomingdale, Carol Stream, Clarendon Hills, Downer s Grove, Glen Ellyn, Hinsdale, Itasca, Lisle, Lombard, Oakbrook, Villa Park, Wayne, Westmont, Willowbrook, Winfield, and Woodridge; the Cities of Aurora, Darien, Elmhurst, Oakbrook, and West Chicago, and the unincorporated areas of DuPage County (hereinafter referred to collectively as DuPage County). The FIS and FIRMs for DuPage County will also show the portion of the Villages of Burr Ridge, Elk Grove, Hanover Park, Schaumburg, and Wayne; the Cities of Chicago and St. Charles that lie within DuPage County. The remaining portions of these communities lie within other counties; these communities have, therefore, been shown on DuPage County FIRMs for informational purposes only. The information contained on the DuPage County FIS for these communities is not to be used for flood insurance purposes. This FIS aids in the administration of the National Flood Insurance Act of 968 and the Flood Disaster Protection Act of 973. This FIS has developed flood risk data for various areas of the county that will be used to establish actuarial flood insurance rates. This information will also be used by DuPage County to update existing floodplain regulations as part of the Regular Phase of the National Flood Insurance Program (NFIP), and will also be used by local and regional planners to further promote sound land use and floodplain development. Minimum floodplain management requirements for participation in the NFIP are set forth in the Code of Federal Regulations at 44 CFR, 60.3. In some States or communities, floodplain management criteria or regulations may exist that are more restrictive or comprehensive than the minimum Federal requirements. In such cases, the more restrictive criteria take precedence and the State (or other jurisdictional agency) will be able to explain them..2 Authority and Acknowledgments The sources of authority for this FIS are the National Flood Insurance Act of 968 and the Flood Disaster Protection Act of 973. This FIS was prepared to include the unincorporated areas of, and incorporated communities within, DuPage County in a countywide format. Information on the authority and acknowledgments for each jurisdiction included in this countywide FIS, as compiled from their previously printed FIS reports, is shown below.

Addison, Village of: Aurora, City of: Bloomingdale, Village of: Burr Ridge, Village of: the hydrologic and hydraulic analyses for this study were performed by Harza Engineering Company of Chicago, Illinois, for the FIA, under Contract No. H-3809. That work was completed in September 976. the hydrologic and hydraulic analyses for the original December 978, study wasperformed by Harza Engineering Company for the FIA under Contract No. H- 3809. That work was completed in October 976. the hydrologic and hydraulic analyses for this study were performed by the Illinois State Water Survey for the FIA under Contract No. H-4522. Analysis of the East Branch DuPage River was coordinated with the USACE, Chicago District. That study was completed in September 979. the hydrologic and hydraulic analyses for this study were performed by Harza Engineering Company for the FIA under Contract No. H-3978. That study was completed in August 978. For the May 5, 986, revision, the hydraulic analyses were obtained from the Illinois Department of Transportation (IDOT). For the January 5, 989, study, the hydrologic and hydraulic analyses were taken from the FISs for the City of Aurora and the unincorporated areas of Kane and DuPage Counties, and from a Soil Conservation Service (SCS) floodplain management study for Indian Creek and Tributaries. For this revision, the hydrologic and hydraulic analyses were prepared by the SCS and the Illinois Department of Transportation, Division of Water Resources (IDOT/DWR). That work was completed in June 989. 2

Carol Stream, Village of: Clarendon Hill, Village of: Darien, City of: Downer s Grove, Village of: Elmhurst, City of: the hydrologic and hydraulic analyses for this study were performed by the USACE, Chicago District, for the FIA, under Inter- Agency Agreement No. IAA-H-6-75, Project Order No. 9 and Inter-Agency Agreement No. IAA-H-7-76, Project Order No.. That study was completed in April 977, and was partially revised in January 98. the hydrologic and hydraulic analyses for this study were performed by Harza Engineering Company for the FIA, under Contract No. H-4562. That study was completed in January 979. the hydrologic and hydraulic analyses for this study were performed by Harza Engineering Company for the FIA, under Contract No. H-3978. That work was completed in April 978. the hydrologic and hydraulic analyses in this study represent a revision of the original analyses by the USACE, Chicago District, for FEMA, under Inter-Agency Agreement No. IAA-H-6-75, Project Order No. 9 and Inter-Agency Agreement No. IAA-H-7-76, Project Order No.. The updated version was prepared by Dewberry & Davis under agreement with FEMA. the hydrologic and hydraulic analyses for the original August 4, 980, study, were prepared by the Illinois State Water Survey (ISWS) for the FIA under Contract No. H- 3942. That work was completed in September 978. For this revision, the hydrologic and hydraulic analyses were prepared by Harza Engineering Company. That work was completed in April 994. Glen Ellyn, Village of: the hydrologic and hydraulic analyses for this study were performed by the Chicago District of the USACE for the FIA, under Inter-Agency Agreement No. IAA-H-7-76, 3

Project Order No. 9. That work was completed in June 977. Hanover Park, Village of: Itasca, Village of: Lisle, Village of: Lombard, Village of: Naperville, City of: Oakbrook, Village of: Oakbrook Terrace, City of: the hydrologic and hydraulic analyses for this study were performed by the USACE, Chicago District, for the FIA, under Inter- Agency Agreement No. IAA-H-7-76, Project Order No. 9. That work was completed in September 977. the hydrologic and hydraulic analyses for this study were performed by the SCS for the FIA, under Inter-Agency Agreement No. IAA-H-7-75, Project Order No. 4. That work was completed in November 976. the hydrologic and hydraulic analyses for this study were performed by the USACE, Chicago District, for the FIA, under Inter- Agency Agreement Nos. IAA-H-6-75, Project Order No. 2; IAA-H-7-76, Project Order No. ; and IAA-H-7-76, Amendment No. 3 to Project Order No.. That work was completed in September 977. the hydrologic and hydraulic analyses for this study were performed by the Chicago District of the USACE for the FIA, under Inter-Agency Agreement No. IAA-H-7-76, Project Order No. 9. That work was completed in June 977. the hydrologic and hydraulic analyses for this study were prepared by the Chicago District of the USACE for the FIA under Inter-Agency Agreement Nos. IAA-H-6-75, Project Order No. 2 and IAA-H-7-76, Project Order No.. That work was completed in February 978. the hydrologic and hydraulic analyses for this study were performed by the Illinois State Water Survey for the FIA, under Contract No. H-3942. That study was completed in September 978. the hydrologic and hydraulic analyses for this study were performed by the Illinois State Water Study for the Federal Insurance 4

Administration, under Contract No. H-4522. This study was completed in September 978. Schaumburg, Village of: St. Charles, City of: Villa Park, Village of: Wayne, Village of: West Chicago, City of: Westmont, Village of: Wheaton, City of: the hydrologic and hydraulic analyses for this study were performed by Harza Engineering Company for the FIA, under Contract No. 3809. That work was completed in October 977. the hydrologic and hydraulic analyses for this study were performed by the USACE, Chicago District, for the FIA, under Inter- Agency Agreement No. IAA-H-8-78, Project Order No. 3. That study was completed in March 980. the hydrologic and hydraulic analyses for this study were performed by the Illinois State Water Survey for the FIA, under Contract No. H-3942. That study was completed in September 978. the hydrologic and hydraulic analyses for this study were performed by the USACE, Chicago District, for the FIA, under Inter-Agency Agreement No. IAA-H-8-78, Project Order No. 3. That study was completed in February 980. the hydrologic and hydraulic analyses for his study were performed by the USACE, Chicago District, USACE, for the FIA, under Inter-Agency Agreement No. IAA-H- 7-76, Project Order No. 9, and Amendment No. 2 to this same agreement. That work was completed in April 977. the hydrologic and hydraulic analyses for this study were performed by Harza Engineering Company for the FIA, under Contract No. H-4562. That study was completed in May 979. the hydrologic and hydraulic analyses for this study were done by the USACE, Chicago District, for the FIA, under Inter- Agency Agreement No. IAA-H-7-76, 5

Project Order No. 9, with amendment. That work was completed in June 977. Willowbrook, Village of: Wooddale, City of: Woodridge, Village of: the source of authority for this FIS is the National Flood Insurance Act of 968, as amended. the hydrologic and hydraulic analyses for this study were performed by the U.S. Department of Agriculture, SCS, for the FIA under Inter-Agency Agreement No. IAA-H- 8-75, Project Order No. 6. That work was completed in August 976. the source of authority for this FIS is the National Flood Insurance Act of 968, as amended..3 Coordination An initial Consultation Coordination Officer s (CCO) meeting is held with representatives of the communities, FEMA, and the study contractors to explain the nature and purpose of the FIS, and to identify the streams to be studied by detailed methods. A final CCO meeting is held typically with representatives of the communities, FEMA, and the study contractor to review the results of the FIS. The dates of the initial and final CCO meetings held for DuPage County and the incorporated communities within its boundaries are shown in Table, "Initial and Final CCO Meetings." TABLE - INITIAL AND FINAL CCO MEETINGS Community Initial CCO Date Final CCO Date Village of Addison * November 0, 976 City of Aurora November 8, 993 April 24, 996 Village of Bartlett January 976 September 5, 980 Village of Bensenville October 4, 984 October 3, 988 Village of Bloomingdale July 9, 977 May 28, 980 Village of Burr Ridge March 976 May 4, 979 Village of Carol Stream January 975 January 9, 98 Village of Clarendon Hills July 977 August 6, 979 City of Darien * January 29, 979 Village of Downer s Grove January 975 June 30, 977 City of Elmhurst August 4, 980 January 8, 980 Village of Glen Ellyn December 975 * *Data not available 6

TABLE - INITIAL AND FINAL CCO MEETINGS - continued Community Initial CCO Date Final CCO Date Village of Hanover Park January 976 June, 977 Village of Hinsdale July 977 December 3, 979 Village of Itasca January 975 October 26, 976 Village of Lisle December 974 June 2, 977 Village of Lombard December 975 September 2, 977 City of St. Charles December 977 October 4, 980 Village of Schaumburg February 3, 975 November 7, 977 Village of Oak Brook August 976 January 0, 980 City of Oakbrook Terrace March 30, 977 January 30, 980 Village of Villa Park August 976 January 2, 980 Village of Wayne * January 6, 98 Village of Westmont July 977 October 29, 979 City of West Chicago January 2, 976 September 5, 977 Village of Willowbrook * January 0, 979 Village of Winfield January 5, 976 June 2, 977 Village of Woodridge * July 22, 976 *Data not available 2.0 AREA STUDIED 2. Scope of Study This FIS covers the geographic area of DuPage County, Illinois. Table 2, Flooding Sources Studied by Detailed Methods, lists the flooding sources that have been studied by detailed methods. Limits of detailed study are indicated on the Flood Profiles (Exhibit ) and/or on the FIRM (Exhibit 2). TABLE - FLOODING SOURCES STUDIED BY DETAILED METHODS 59 th Street Ditch 63 rd Street Ditch 79 th Street Ditch Addison Creek Addison Creek Tributary No. Addison Creek Tributary No. 2 Addison Creek Tributary No. 3 Armitage Creek Armitage Fork Brewster Creek Briarwood Ditch Bronswood Cemetery Tributary Crabtree Creek Cress Creek Des Plaines River Devon Avenue Tributary East Branch DuPage River East Branch Lacey Creek East Branch Sawmill Creek East Branch Tributary No. 3 East Branch Tributary No. 4 Ferry Creek Ferry Creek Tributary No. Flagg Creek Ginger Creek Heritage Oaks Tributary Klein Creek Kress Creek Lacey Creek Lombard Tributary 7

TABLE - FLOODING SOURCES STUDIED BY DETAILED METHODS continued Meacham Creek Midwest Club Tributary North Branch St. Joseph Creek North Unnamed Creek Norton Creek Norton Creek Tributary Plainfield Road Ditch Prentiss Creek Salt Creek Sawmill Creek South Branch St. Joseph Creek South Fork of Westwood Creek South Unnamed Creek Spring Brook Creek Spring Brook No. Spring Brook No. 2 Spring Road Tributary St. Joseph Creek St. Joseph Creek Tributary St. Procopius Creek Sugar Creek Sugar Creek Tributary A Tributary (A) Tributary B Unnamed Creek South of Foxcroft Road Unnamed Stream North of 22 nd Street Unnamed Tributary to Kress Creek Waubansee Creek West Branch DuPage River West Branch Sawmill Creek West Branch Tributary No. West Branch Tributary No. 2 West Branch Tributary No. 3 West Branch Tributary No. 4 West Branch Tributary No. 6 West Branch Tributary to Spring Brook Creek Westwood Creek Winding Creek Winfield Creek According to the State Water Survey, East Branch Tributary No. 4 is also known as Glen Crest Tributary. For this revision, 6,300 feet of the main channel of East Branch Tributary No. 2 was studied by detailed methods starting from a detention pond on the north side of James Court serving a subdivision in Glendale Heights north of North Avenue extending up to a point just upstream of Main Street. The areas studied by detailed methods were selected with priority given to all known flood hazard areas, and areas of projected development or proposed construction. Approximate methods of analysis were used to study those areas having a low development potential or minimal flood hazards. The scope and methods of study were proposed to and agreed upon by FEMA and the unincorporated areas of DuPage County. 2.2 Community Description DuPage County is situated in northeastern Illinois, approximately 25 miles directly west of the City of Chicago. DuPage County is bordered by Cook County on the north and east, Will County on the south, and Kane County on the 8

west. The county encompasses 332. square miles and had a 2000 residential population of 904,6 according to the 2000 U.S. Census. The gross residential density of 2000 was 2,722 people per square mile. Approximately 200 square miles or 60 percent of the county is in unincorporated areas. Temperature data is published for two climatological stations in DuPage County, Wheaton, and Argonne National Laboratories. The average annual temperature of Wheaton which is typical for these stations, and for the county as well, is 49.8 degrees Fahrenheit ( F) with an annual monthly high in July of 76.5 F and monthly low in January of 9.2 F. The annual average precipitation at Wheaton is 39.26 inches. The highest monthly average precipitation occurs in August with a value of 7.65 inches (U.S. Department of Commerce, 975). There are four major drainage basins in DuPage County. These are: the West Branch DuPage River, the East Branch DuPage River, Salt Creek, and the Des Plaines River. The West Branch DuPage River, the East Branch DuPage River, and Salt Creek all run from north to south and divide the county into four vertical strips. The Des Plaines River flows along the southeastern boundary of DuPage County. The West Branch DuPage River flows southward near the western edge of the county. This river flows through the communities of Bartlett, Winfield, West Chicago, Warrenville, and Naperville. The East Branch DuPage River flows southward in the central portion of the county. Communities that are adjacent to this river are Glendale Heights, Lombard, Glen Ellyn, Downers Grove, and Lisle. The major tributaries studied in this drainage basin are Prentiss Creek, St. Joseph Creek, and Lacey Creek. Salt Creek is a tributary of the Des Plaines River. It flows southward from the northern section of Cook County to Oak Brook, then eastward to its confluence with the Des Plaines River, at Lyons. The Des Plaines River, located in the southeastern section of the county, flows southwest to its confluence with the Illinois River at Joliet. Sawmill Creek, Illinois and Michigan Canal, Chicago Sanitary and Ship Canal, and some minor tributaries were studied in the Des Plaines River basin. There is a minimal amount of development within the floodplains of DuPage County. This is because all development within the floodplains is regulated by the DuPage County Zoning Ordinance of 935 (DuPage County Zoning Ordinance, 935). 2.3 Principal Flood Problems In the unincorporated areas of DuPage County, flood peaks have been increasing because of recent urbanization of the uplands with resultant greater runoff. 9

Urbanization is often accompanied by filling of the floodplain or by encroachment upon it, which reduces channel conveyance capacity. Increased floods on the main channels cause backwater effects up their tributaries. Additional flood runoff is unable to flow through restricted culverts and bridge openings, which often are clogged with sediment and debris from new construction. The problems associated with urbanization are further complicated by inadequate channel improvements. Flood damages include residential, some business and commercial damage, road closures with corresponding transportation disruption, school closures, and agricultural, with residential absorbing the greatest damage. The floodwater enters sanitary sewers through street manholes, and floods basements and lower levels causing major cleanup problems and health hazards. More severe floods gain direct entrance to basements, subground living areas, and lower-level garages through surface runoff. This type of flood causes some minor structural damage. Very rarely do floods enter first-floor levels by direct surface runoff; however, when this does occur, there is usually major damage to structures and contents. Another major type of flood damage is the flooding of highways and local roads which results in considerable costs incurred by delays in travel. These flooded roads impede emergency vehicles and vehicles providing necessary goods and services, and will often close schools because of lack of access. Another type of flood damage is neighborhood degradation caused by frequent flooding. This type of damage usually results in declining property values within the flooded area. The impact of this type of damage is difficult to determine due to the many factors which influence the way property values change over time. Estimates for flood damages are not available for the unincorporated areas of DuPage County. Floods have occurred in the study reaches of the DuPage River Basin and its tributaries during all seasons of the year. The greatest recorded flood occurred in August 972. Flooding has usually resulted from heavy thunderstorms following a period of prolonged rainfall that had saturated the ground. The major storm of August 972 was preceded by a heavy rainfall for two days. During the winter months, flooding has usually been a result of heavy rainfall on frozen ground. Snowmelt can also be a factor in late winter or early spring. Because of the high runoff associated with saturated or frozen ground, stream flow stages in this area can be expected to rise quickly from normal to flood levels. 0

Principal Flood Problems for the Des Plaines River Watershed Watershed s major tributaries Flagg Creek The past history of flooding on Flagg Creek within the Village of Clarendon Hills indicates that flooding may occur during any season of the year. The majority of floods have occurred during March, April, and May; they are usually the result of spring rains and/or snowmelt. The 00-year discharge varies from 380 cfs at the downstream corporate limit to 90 cfs at the Eastern Avenue bridge. No high water marks are known to exist on Flagg Creek within the study area. Damaging floods on Flagg Creek can be documented from discharge records for the USGS gage on Flagg Creek at Willow Springs (U.S. Department of the Interior, 975). This gage (no. 05533000, drainage area 6.5 square miles) was established in 949, and records are continuous to the present. The most severe floods in the Flagg Creek basin are listed below. Approximate Recurrence Water Discharge Interval Year (cfs) (years) 96 2,680 85 976 2,230 40 975,630 5 959,550 2 957,350 8 955,300 7 The portion of Flagg Creek flowing within the Village of Hinsdale flows through an underground culvert. For small flood events, the flow is contained in the culvert. For large floods, the culvert becomes surcharged and ponding occurs in the low-lying areas above the underground culvert. For a portion of 59 th Street Ditch, the culvert is incapable of containing the 00-year storm, thus causing overland flow. Plainfield Road Ditch Flooding at Plainfield Road Ditch occurs on farmland just west of the Tri-State Tollway and, in a milder form, at the International Harvester Company. No buildings are flooded. In both cases, shallow channels contribute to the flooding.

59 th Street Ditch Flooding occurs on the 59 th Street Ditch when flow from upstream exceeds the capacity of the underground conduit system. Floodwaters flow through the subdivision known as Wood View Estates. On the east side of the subdivision, the water flows into a drainage ditch along the Tri-State Tollway. The water then flows south into 63 rd Street Ditch, then east into Flagg Creek. 63 rd Street Ditch The entire reach of 63 rd Street Ditch east of State Route 83 in the Village of Willowbrook is subject to overbank flooding as described in the Hydrologic Atlases (U.S. Department of the Interior, HA-86, 963; U.S. Department of the Interior, HA-49, 963) and the report of the Des Plaines River Steering Committee (Des Plaines River Watershed Steering Committee, 975). In addition, Wight and Company, in their Stormwater Management Study for Willowbrook, describes two areas draining to the 63 rd Street Ditch which have been flooded (Wight and Company, 977). One of these is at the corner of 59 th Street and Clarendon Hills Road where flooding is due to inadequate drainage. This area flows into Marion Hills Ditch. The other is an area of overbank flooding along 63 rd Street Ditch downstream from Lake Hinsdale to 63 rd Street Ditch near Ridgemoor Drive and Quincy Drive. 79 th Street Ditch Frequent residential damage occurs in one area in the Village of Burr Ridge. Flooding problems principally are caused by development in low lands which formerly served as natural drains. Overflow of the 79 th Street Ditch causes damage to a residence on Hamilton Avenue south of 77 th Street. The channel of this stream is not well defined in many places. This results in flooding of streets and yards in the area south of the intersection of 79 th Street and Drew Avenue. Principal Flood problems for East Branch DuPage River Watershed Flooding along the East Branch DuPage River is minimal due to the construction of Westlake Lake which is designed for a 00-year event. The total drainage area is,350 acres, most of which is residential. Lake Illini, the retention lake for the Indian Lakes subdivision, drains to the East Branch DuPage River. This development is built on a broad, shallow, perched valley. During intense rainfalls, standing water occurs in areas of equal elevation to Lake Illini. Because of a high water table of roughly 778 feet, only two feet of storage is available before the designed 00-year level of 780 feet is exceeded. The Village of Bloomingdale is studying ways to prevent this flooding, but no projects have been built as yet. 2

Flood stages on the East Branch DuPage River are monitored by USGS gage no. 554040. The three highest recorded floods for the stream are summarized in the following tabulation (U.S. Department of the Interior, 978): FLOOD STAGES WATER-SURFACE DISCHARGE RETURN PERIOD DATE ELEVATION (cfs) (years) GAGE NO. 554040 AT ARMY TRAIL ROAD EAST BRANCH DUPAGE RIVER 8/26/72 707.93 204 0 4/8/75 706.97 05 9/26/77 706.78 9 The portion of the East Branch DuPage River flowing through the Village of Glen Ellyn presents the most severe flood hazard within Glen Ellyn. Recent floods along the East Branch DuPage River have occurred in April 950, October 954, September 96, and August 972. The August 972 flood produced a discharge approximately equal to the computed 50-year discharge at Maple Avenue in the Village of Lisle. Recorded crests for this flood at two Illinois Division of Water Resources crest-stage gages near Glen Ellyn are as follows (U.S. Department of the Interior, 973): Location Elevation (feet NGVD) Butterfield Road 676.44 St. Charles Road 69.24 Damages in the Village of Glen Ellyn from overflow of the East Branch DuPage River and accompanying storm sewer back-up problems during the 972 flood totaled approximately $500,000 for private homeowners and $40,000 for the Village of Glen Ellyn (Glen Ellyn News, 972). Since discharge data are not available for the 950, 954, and 96 floods, it is not possible to give an accurate estimate of their frequency. High water marks for these floods are indicated in (U.S. Department of the Interior, 964; U.S. Department of the Interior, 965). The East Branch DuPage River and St. Joseph Creek have been sources of greatest concern in the Village of Lisle. Flooding has been reported on the East Branch DuPage River in 948, 950, 954, 957, and 972. Flooding on St. Joseph Creek and the East Branch DuPage River in October 954 caused the evacuation of many people. Water covered parts of Ogden Avenue, State Highway 53, Burlington Street, McKinley Avenue, Dumoulin Street, and River Drive. Flood waters reached the top of the Burlington Northern Railroad overpass on Main Street. A severe thunderstorm in July 957 reportedly dropped 7.7 inches of rain in six hours in nearby Downers Grove, causing flooding along 3

St. Joseph Creek in Lisle. The August 972 flood, however, proved to be the flood of record on the East Branch DuPage River and the most damaging in the area. The 972 flood is estimated to have a recurrence interval of about 50 years and resulted in a peak discharge on the East Branch DuPage River at village of Lisle of 2,500 cubic feet per second. Torrential rains were reported in excess of 7 inches in three hours in localized measurements. Crabtree Creek Flooding has occurred along Crabtree Creek, although most of the damages incurred during high stages of this stream result from basement flooding caused by sewer back-up. Signs of stream bank and bed erosion, caused by high water velocities, are evident along Crabtree Creek. East Branch Du Page River Tributary No. 2 Flooding problems have occurred at several locations in the Tributary No. 2 watershed, although these problems have generally been limited to yard flooding and road overtopping. Flooding has been reported by residents on Main Street, 2 nd Street west of Forest Avenue, and along Park Avenue. Road overtopping has been reported on Main Street and Glenrise Avenue. Lacey Creek Low-lying areas of the watershed are subject to periodic flooding caused by overflow of the various watercourses within the community. The most severe flooding occurs in late summer as a result of heavy thunderstorms following periods of prolonged rainfall that have saturated the ground. Flooding during the winter months has usually been a result of heavy rainfall on frozen ground. Repeated damage to structures has occurred during past floods, especially those of October 954, July 957, and August 972. The most severe flood of recent record occurred in August 972, when flood waters rose near Belmont Avenue to an elevation of 69.3 feet on St. Joseph Creek (Downers Grove Reporter, 954, et cetera). Based on the past history of floods within the area, this flood had a recurrence interval of 0 years. Prentiss Creek Prentiss Creek presents the most severe flood hazard within the Village of Woodridge. Floods along Prentiss Creek, as well as along the village s other streams, are usually highest in early spring, resulting from heavy rainfall and rapid snowmelt. Flooding along the creek is often aggravated by debris accumulation. Although just outside of the village limits, the constrictive culvert under State Route 53 causes substantial flooding of lands located just upstream of the bridge. Overbank flooding along Prentiss Creek is usually accompanied by back-up of street storm sewers and basement drains, two problems not specifically addressed by this study. Another major cause of flooding along 63 rd Street is the 4

inadequate capacity of the underground pipe which carries a small tributary stream from just upstream of 63 rd Street at Winston Street to Prentiss Creek. A profile of the July 963 flood, Prentiss Creek s flood of record, is available. Recorded flood crest elevations for the USGS crest-stage gage at State Highway 53 are as follows: Prentiss Creek at State Highway 53 (downstream) Flood Flood Crest Elevation (NGVD) July 963 663.94 August 972 663.8 Accurate estimates of the recurrence intervals for these floods cannot be made since the above flood crest elevations were affected by backwaters from the East Branch DuPage River, and corresponding discharges are not available. Unnamed Tributary North of 22 nd Street The principal cause of flooding in the area is the inadequate capacity of the natural channel to contain the runoff resulting from intense thunderstorm precipitation over the basin. Inundation of lands adjoining the river channel has been aggravated over the years by the gradual accumulation of silt. Buildup of sand bars and islands in the channel has resulted in the loss of channel capacity. Another factor lending itself to the poor flow characteristics of the channel in some reaches is the excessive growth of brush, light timber, and aquatic vegetation. In the past, the watershed has experienced almost none of the flood problems associated with the overflow of streams from their natural channels. As discussed above, the reason for this can be attributed to the undeveloped nature of the floodplain areas. However, the watershed has experienced flood damages as a result of the ponding of runoff compounded by the inability of the storm sewer system to convey the storm waters away in a timely manner. Principal Flood problems for the Sawmill Creek Watershed Sawmill Creek and West Branch Sawmill Creek Inadequate storm sewers and out-of-bank flooding along Sawmill Creek and its tributaries, East Branch Sawmill Creek and West Branch Sawmill Creek cause principal flood problems in the City of Darien. Flooding from inadequate sewers occurs in the area bounded roughly by Plainfield Road and Willow Lane. Flood damages include residential damages, traffic disruptions, and associated neighborhood degradation caused by frequent flooding. There are no discharge 5

gages located on Sawmill Creek, and peak discharges for past floods are not available. East Branch Sawmill Creek Flooding occurs along the entire reach of East Branch Sawmill Creek in the Village of Willowbrook. The June 3, 976, flood caused damage along Eleanor Place and Virginia Court south of 75 th Street and north of 79 th Street. Floods on East Branch Sawmill Creek generally occur at the same time as those on Flagg Creek. The Flagg Creek basin borders the Sawmill Creek basin on the north and west. Principal Flood problems for the Salt Creek Watershed Low-lying areas of the City of Wood Dale are subject to periodic flooding caused by overflow of Salt Creek. As a result, storm drain outfalls become blocked and areas along small tributaries are flooded. The blocked storm runoff infiltrates the sanitary sewer system, creating sewer overloads and subsequent basement backup. Repeated damage to structures in the floodplain of Salt Creek has occurred during such floods as those in 957, 960, 96, 966, 967, 968, 972, and 973. The worst floods occurred in 954, 967, and 972. The floods of 954 and 967 both have an estimated recurrence of 0 years as estimated by SCS and the flood of 972 has an estimated recurrence interval of 25 years as estimated by the USGS. Principal flood problems in the Village of Addison are street flooding caused by inadequate storm sewers and out-of-bank flooding along Salt and Westwood Creeks (U.S. Department of Agriculture, 976). A USGS crest-stage recorder is located on Salt Creek at the Lake Street bridge. The flood-of-record occurred on August 27, 972. An official or published discharge value for Salt Creek at Addison is not available. Stage-discharge relationships developed by Harza indicates that this flood had a peak discharge of about 3,340 cubic feet per second (cfs), a 50-year event. A 973 report (U.S. Department of Agriculture, 976) indicated that about 700 homes were within the flooded area of which about 500 applied for Federal aid after the flood had receded. Major damage was attributed to basement flooding by direct overland flow through windows or seepage through wall or foundation cracks. Additional damage occurred in some residences due to back-up through combined sewers. Dollar estimates of the damages are not available. Overflow of Spring Road Tributary and Salt Creek also causes principal flood problems in the City of Oakbrook Terrace. The Spring Road Tributary is ungaged. The best historical data available for flooding in Oakbrook Terrace are from a USGS recorder gage on Salt Creek, just north of Western Springs at Wolf Road about 7,000 feet downstream of the eastern corporate limit (U.S. Department of the Interior, 976). At this point, Salt Creek has a drainage area of 4 square miles, and there is 3 years of data from the Western Springs gage 6

(U.S. Water Resources Council, 976). The 5 most significant floods of record are tabulated below: Discharge Gage Height Total Height Date (cfs) (feet) (feet) March 20, 948,920 8.06 632.99 August 28, 972,790 8.55 633.48 October 0, 954,70 8.27 633.20 April 9, 975,600 8.4 633.07 May 2, 966,460 7.63 632.56 Devon Avenue Tributary Devon Avenue Tributary overflow causes periodic flooding in the low-lying areas of the Village of Itasca. As a result, storm drain outfalls become blocked and areas along small tributaries are flooded. The blocked storm runoff infiltrates the sanitary sewer systems, creating sewer overloads and subsequent basement backup. Repeated damage to structures in the floodplains have occurred during such floods as those in 957, 960, 96, 966, 967, 968, 972, and 973. Spring Brook Creek and West Branch Tributary to Spring Brook Creek Spring Brook Creek drains the north sector of the Village of Bloomingdale. Flooding occurs because of inadequate channel capacities due to increased runoff from developing land to the south and north, the Village of Roselle. In the upper portion of the West Branch Tributary to Spring Brook Creek, flooding occurs because the land is flat, marshy, and has no well-defined course because of considerable debris in the channel. After it crosses Lake Street, the West Branch Tributary to Spring Brook Creek flows northerly where the channel is well defined and flow is less obstructed. Flooding along the mainstem of Spring Brook Creek occurs downstream of the confluence with the West Branch Tributary to Spring Brook Creek. The creek is well defined but is usually clogged with debris. Flooding occurs because the gradient is much less than the upper reaches. Most flooding is confined along a narrow belt, paralleling the channel. Flood stages on Spring Brook Creek are monitored by USGS gages no. 553080. The three highest recorded floods for the stream are summarized in the following tabulation (USGS, 978): 7

FLOOD STAGES WATER-SURFACE DISCHARGE RETURN PERIOD DATE ELEVATION (cfs) (years) GAGE NO. 553080 SPRING BROOK CREEK 8/26/72 74.0 645 50 /27/74 70.25 263 4/8/75 40.6 256 Principal Flood problems for the West Branch Dupage River Watershed Flooding along the West Branch DuPage River in the Village of Hanover Park is frequent and severe. Rapid urbanization in the drainage area since 960 has led to increasing storm runoff, while at the same time, development in the floodplain in the north portion of the village has obstructed overbank flows during floods, raising water-surface elevations in the vicinity and generally worsening the damage conditions. A major storm in October 954 caused record flooding in the Chicago area but Hanover Park was sparsely developed at that time. Other significant floods occurred on June 0, 967, and on September 6, 970, with an estimated 2.7 inches of rainfall in the drainage area. Peak discharges at the crest stage gage at Lake Street on the West Branch DuPage River reached 570 cfs in 967 and 450 cfs in 970. Damages in Hanover Park resulting from the 970 flood were estimated at $470,000. In addition to flooding due to major storms, more frequent flooding occurs due to high waters in the river blocking storm sewer outlets and causing basement flooding (Harza Engineering Company, 97). West Branch DuPage River also causes flooding within the City of Naperville. The amount of land subject to inundation within the City of Naperville from the West Branch DuPage River was significantly reduced by the construction of the Fawell Dam, just north of Naperville, by the Illinois Division of Water Resources in July 972. The natural topography of the City of Naperville, particularly in the north-central portion of the city, has always been inadequate for the removal of storm water without some degree of total surface ponding occurring. This problem has been aggravated, however, by the continued development within Naperville which has decreased the amount of uncovered ground available for saturation by precipitation. Major destructive floods along the West Branch DuPage River occurred in March 948, April 950, October 954, July 957, and August 972. For the Illinois Division of Water Resources stream gage near Warrenville, the maximum recorded discharge occurred on August 26, 972. Although records for this gage begin only in 968, a high-water mark near the Warrenville gage indicates that the October 954 flood conveyed even a greater discharge. 8

Although the Warrenville stream gage crested on August 26 during the August 972 flood, the majority of the damage within Naperville resulted from a storm occurring a few days later, on August 29, when an average of 5.9 inches of rain fell over the West Branch DuPage River Basin over a 5-hour period. Rain gages at two of Naperville s sewage plants registered 4.75 and 5.25 inches of rainfall. As a result of the Fawell Dam s recent construction, the West Branch DuPage River was reported to leave its banks only in the city s southern portions. Some of the most severe flooding within Naperville took place along Huffman and Porter Streets due to storm sewer overflow and local ponding. Property damage from the August 972 flood was estimated in excess of $.5 million for the Naperville area. During the period of October 9-, 954, the West Branch DuPage River Basin received an average of approximately 7.5 inches of rain, while Naperville received in excess of 9 inches. The gage at Shorewood, on the DuPage River, registered its highest recorded discharge for this storm. Klein Creek The principal causes of flooding in the area are the inadequate capacities of the natural channels to contain the runoff resulting from intense thunderstorm precipitation over the watershed. Additional flooding problems are created by the many channel and floodway constrictions resulting from inadequate waterway openings at bridges and the floodplain encroachments in urban areas. Many of the bridges, principally those along Klein Creek, have inadequate waterway openings which cause increased water stages and flooding upstream of the bridge when discharges exceed their capacity. A matter of serious concern has been the growth of urban development on the floodplain of the river. This haphazard occupation of the floodplain has resulted in constriction of both the channel and available floodways. Houses, garages, fences, and related construction have been built on the immediate banks of the river without adequate consideration of their effect on flood flows on the river and are subject to early inundation in high water stages and also serve to block effective flow of the floodwaters. Today, the village uses the Ven Te Chow method (Chow, 964) for computing storage requirements for developing areas, which by its nature is restrictive and alleviates the magnitude of existing flooding. Repeated damage to structures in the floodplains has occurred during such floods as those that occurred in 942, 947, 948, 949, 950, 95, 953, 954, 957, 959, 96, 962, 966, 967, 972, and 975. High water marks available along Klein Creek indicate elevations of approximately 743 feet in October 954 and 743 feet in June 962. Both of these storms have an estimated 0-year recurrence interval. Klein Creek drains the southwest section of the Village of Bloomingdale. Construction commenced on this property in 979 and converted 77 percent of the 9

area north of Army Trail Road from agricultural to commercial/residential use. Flooding occurs here because of a naturally high water table and soil which drains poorly. The worst flooding occurred during the August 972 storm when a watersurface elevation of 765.5 feet was reached at Army Trial Road. This elevation correlated well with a predicted 767.7 00-year elevation from a USACE study (USACE, 975). The flood areas shown on the Flood Boundary and Floodway Map were provided by Mackie Consultants, the engineer for the developer (Mackie Consultants, Inc., 977). Kress Creek Discussions with city representatives revealed that the major flood problems in West Chicago have been along Kress Creek. The greatest flood in the West Chicago area occurred in October 954. Flood delineations for this event in West Chicago, taken from the Hydrologic Investigations Atlases (U.S. Department of the Interior, 965, et cetera), indicate that areas adjacent to Kress Creek were flooded up to widths of,000 feet, while the Unnamed Tributary to Kress Creek was minimally affected. During the 954 flood along the West Branch DuPage River, the portion of West Chicago upstream of State Highway 38 was flooded up to 250 feet from the channel on the right (west) bank, while downstream of the highway the left (east) bank was flooded for a distance of up to 350 feet from the channel. The peak discharge for the 954 flood on the West Branch DuPage River in West Chicago had a recurrence probability of about 50 years. Specific damage estimates in West Chicago during the 954 or 972 floods were not found in the newspaper accounts of the flooding. No photographs of past flooding in West Chicago could be found. Winfield Creek Principal flood problems in the City of Wheaton include overbank flooding from Winfield Creek, as well as local ponding of storm runoff at several locations. Major floods have occurred along Winfield Creek in May 954, October 954, and August 972. Although the May 954 flood caused only minor damage, substantial damages were sustained during the October flood of the same year. The following areas are among those hardest hit in the City of Wheaton during the October 954 flood: areas surrounding Winfield Creek near North Side Park and Gary Avenue, the East Hawthorne subdivision, the area near Wheaton High School and the Wheaton Sanitary District plant on Weisbrook Road (Wheaton Experiences Much Loss, 954). The August 972 flood was the flood of record for Winfield Creek. Several cars were washed into Winfield Creek at Main Street from streets and parking lots. Damages during the 972 flood in Wheaton were set at $5,055,000 ( Damage Estimate Set, 972). Gage readings for the August 26, 972, flood along Winfield Creek are as follows (U.S. Department of the Interior, 973): 20

Record Elevation Gage Location (NGVD) Spring Brook Creek Winfield Road 70.57 Warrenville Road 73.23 Winfield Creek Route 38 72.28 Gary Avenue 73.67 A discharge of 455 cfs was estimated at the Warrenville Road gage for Spring Brook Creek during the 972 flood (U.S. Department of the Interior, 973). This figure is slightly larger than the computed 00-year flood peak discharge of 430 cfs. No discharge data are available for Winfield Creek. 2.4 Flood Protection Measures After experiencing the damaging effects of flooding from the August 987 flood event, the county began to take measures to protect against future flooding. In 989, the county began construction of over $00 million in flood control projects, the strict enforcement of a comprehensive stormwater and floodplain ordinance, and the development of updated regulatory floodplain maps throughout the county. These principal improvements were managed by a new entity, the Stormwater Management Division (SMD). This new organization is a division of the DuPage County Department of Environment Concerns (DEC). The SMD has managed the planning, design, and construction of many major flood control facilities over the last 2 years. The main purpose of the SMD implements the countywide stormwater ordinance. The SMD developed the countywide stormwater and floodplain ordinance in 99, and started enforcement of the ordinance in February 992. In 2000, DEC became the Department of Development and Environmental Concerns, and is still known as the DEC. Streams that had less than one square mile of drainage area were studied using limited detailed analysis; therefore, only the 0-year and 00-year water-surface elevations were computed. No floodway was computed for those streams. The streams studied using this method were: East Branch Tributary No. East Branch Tributary No. 2 East Branch Tributary No. 5 East Branch Tributary No. 7 Klein Creek Tributary No. Klein Creek Tributary No. 3 West Branch Tributary No. 5 West Branch Tributary No. 7 Sawmill Creek Tributary No. Wards Creek Some of the streams listed above are known by other names according to the State Water Survey. East Branch Tributary No. 5 is also known as Leask Creek, East Branch Tributary No. 6 is also known as East Branch Tributary No. 2, East Branch Tributary No. 7 is also known as Armitage Ditch, and West Branch No. 2 is also known as Country Creek. 2

Principal Flood Protection Measures for the Des Plaines River Watershed Addison Creek The State of Illinois has proposed a reservoir project on Addison Creek. The County Board has enacted an ordinance amending the DuPage County Zoning Ordinance regulating floodplain and wetland areas (DuPage County Zoning Ordinance, 935). This ordinance provides that no floodplain and/or wetland area shall be disturbed, reshaped, or otherwise affected by: channel relocation, channel deepening, filling or grading of any type, the erection of any structures, or the storage of any materials or equipment, except as permitted by a special use ordinance. The minimum floodplain elevation is defined as that elevation determined from the flood crest profile of the highest flood of record. Flagg Creek There are no dams or reservoirs within the Flagg Creek. The main channel of Flagg Creek was improved in the past by paving a part of the channel between State Route 83 and Harris Avenue. Within the watershed, there are three facilities which provide some flood relief for local areas. These include the two interconnected detention ponds in Prospect Park, the Blue Lake detention area, and a grassed detention area in Hudson Park. These ponds do not have storage capacity for severe flooding events. The stream is not regulated by any floodplain management ordinance. 59 th Street Ditch All of 59 th Street Ditch within the Village of Hinsdale flows through an underground culvert. For small flood events, the flow is contained in a culvert. For large floods, the culvert becomes surcharged and ponding occurs in the lowlying areas above the underground culvert. The culvert is incapable of containing the 00-year storm, thus causing overland flow. There are no existing dams and reservoirs for the portion of the 59 th Street Ditch flowing within the corporate limits of the Village of Hinsdale. Village ordinances require detention of flood discharge in excess of 0. inch per hour for the 00-year storm for any new developments. 63 rd Street Ditch The Village of Burr Ridge has taken an active interest in solving its flooding problems, including contracting with Lindley and Sons, Inc., to investigate the problem. The retention pond near the mouth of 63 rd Street Ditch has been designed to retain 00-year flood flows for a short period of time without affecting the surrounding homes. There is a small lake on the International Harvester Company property along Plainfield Road Ditch. Some flood runoff will spill into this lake, but the lake is too small to reduce the peak flood discharge. For the portion of the stream flowing through the Village of 22

Willowbrook, the community has previously completed several projects, including improving culverts and channels to reduce flood peaks. Lake Hinsdale, with a storage volume of about 35 acre-feet, controls discharges to 63 rd Street Ditch from portions of the watershed west of Kingery Highway. Principal Flood Protection Measures for the East Branch DuPage River Watershed Following the floods of 954 and 957 in the Village of Lisle, new emphasis was given to studies for the East Branch DuPage River. A Survey Report for Flood Control was completed in 962 by the Department of Public Works and Buildings, Division of Waterways, covering this stream (State of Illinois, 962). Subsequently, the East Branch DuPage River channel has been enlarged and levees built on both sides of the channel in the area from the Burlington Northern Railroad crossing to Middleton Avenue. From Maple Avenue to the Burlington Northern Railroad crossing, a levee was constructed on the east bank only. The levees along the East Branch DuPage River at Lisle will be overtopped by the 00-year flood. The USACE, Chicago District, initiated a three-year study, which included the DuPage River Basin, in the spring of 975. This study is investigating the feasibility of solutions to urban water damage problems caused by overbank flooding and poor drainage in northeastern Illinois and northwestern Indiana. The investigation of drainage problems will be limited to sewer back-up caused by surcharging of drainage outlets by high river stages. The Village of Lisle, in December 970, adopted an ordinance regulating construction in floodplain or wetland areas, without appropriate safeguards against flood damage. A permit system through the office of the village engineer is the regulatory medium under this ordinance. For the portion of East Branch DuPage River flowing through the Village of Glen Ellyn, in the past, damages associated with storm sewer back-up have been significant during periods of intense rainfall. In order to avoid these street and basement flooding problems, several detention and retention ponds have been constructed within the Village of Glen Ellyn. These include the retention pond system at the Village Links golf course and the detention ponds at Panfish Park and Glen Ellyn Manor. During the August 972 storm, no significant flooding was reported by areas serviced by the Village Links storm retention system. There are two low-flow dams located on the East Branch DuPage River. One is located in the Morton Arboretum near the Village of Lisle and the other is a controlling structure for the Churchill Hills Lagoon. There are no Federal flood control structures on the East Branch DuPage River or its tributaries within the unincorporated areas of DuPage County. East Branch Tributary No. 2 One of the flood protection measures that has been implemented in East Branch Tributary No. 2 is an overflow channel to handle high flow between Main Street 23

and Park Boulevard. Low flows are carried in a corrugated metal storm sewer, and an overflow channel is provided for high flows. A crossover structure just east of Main Street is designed to assure full flow in the storm sewer before flow enters the overflow channel. There is also an overflow basin located between Forest and Park Street in the south side of Second Street, which detains flow when the capacity of the Second Street storm sewer is reached. Stream bank stabilization was completed by DuPage County on the overflow channel in 994 for the reach between Main Street and Forest Avenue, and the reach between Park Boulevard and Goodrich Avenue. Between Forest Avenue and Park Boulevard, the overflow passes through a wide grassy area that may have been designed for flood storage. Prentiss Creek Development of floodplains for Prentiss Creek flowing within the Village of Woodridge is currently regulated by Article III, Section 3.25 of the village s zoning ordinance. This section stipulates that no buildings may be constructed within those areas delineated as floodplains on the Hydrologic Atlas maps prepared by the USGS, in cooperation with the Northeastern Illinois Planning Commission (U.S. Department of the Interior, HA-48, 965; U.S. Department of the Interior, HA-46, 965). As the areas near Prentiss Creek have been residentially developed, substantial filling has occurred, and portions of the stream have been realigned. This is particularly true in that reach of the stream between State Route 53 rd and 63 rd Street. An independent citizens committee, the Prentiss Creek Flood Committee, has been formed to investigate solutions to flooding along Prentiss Creek. Additionally, the Village of Woodridge has recently begun discussions with neighboring communities to consider the regulation of storm runoff into Prentiss Creek. St. Joseph Creek and St. Joseph Creek Tributary Following the floods of 954 and 957, new emphasis was given to study for St. Joseph Creek. A Survey Report for Flood Control was completed in 962 by the Department of Public Works and Buildings, Division of Waterways, covering this stream (State of Illinois, 962). St. Joseph Creek has been straightened and enlarged from its mouth to Curtiss Street in the portion flowing through the Village of Downers Grove. Channel and culvert improvements along St. Joseph Creek have significantly reduced the flood potential in some areas. During the flood of October 954, extensive damage occurred in the downtown business area of the Village of Downers Grove. The village subsequently dredged a portion of St. Joseph Creek and that, together with clearing of debris from the channel, eliminated the flooding in the downtown area during the July 957 flood. At the present time, a culvert from Mackie Avenue to Carpenter Street prevents the 00- year flood waters from reaching the downtown business area. An earthen berm has been constructed just upstream of 55 th Street to further reduce the flooding of downstream areas. The Village of Downers Grove has established Floodplain Reservation Areas to protect the floodplains within the village limits. New 24

development must be 3 feet above the historical flood of record as shown on the flood-prone area maps for Hinsdale and Wheaton, Illinois, prepared by the USGS in cooperation with the Northeastern Illinois Planning Commission (U.S. Department of the Interior, 963, et cetera). Unnamed Tributary North of 22 nd Street There are no flood protection works on streams in the area. However, the area has an active storm water management program to alleviate some of the problems attributed to the ponding of runoff. Principal Flood Protection Measures for the Fox River Watershed Fox River is a major tributary of the Illinois River. Its watershed covers an area of approximately 2,580 square miles, of which,640 square miles are in Illinois. Two tributaries to this watershed start in DuPage County. Norton Creek There are no flood protection structures or measures such as concrete-lined channels, detention ponds, storage reservoirs, or local laws which affect the Norton Creek. Waubansee Creek There are two on-channel surface reservoirs on Waubansee Creek just upstream of the crossing of the Elgin, Joliet and Eastern Railway. Construction of the reservoirs meets FEMA requirements for consideration in hydraulic analyses. They are being developed by a private development company for flood control related to urbanization. In addition to reservoirs, on-site retention, storage is being installed throughout the watershed wherever substantial residential or commercial construction is taking place (State of Illinois, 975). Principal Flood Protection Measures for the Salt Creek Watershed On Salt Creek, there is an existing low-flow dam at Oak Brook. There are a number of proposed reservoir projects in the Salt Creek watershed. Two reservoirs are proposed on Meacham Creek near Roselle, and another on Salt Creek at Elmhurst. These three projects are currently being sponsored by the SCS. One flood water retarding reservoir on Salt Creek (Busse Woods Reservoir) is under construction approximately one mile upstream of the Village of Itasca. Construction was scheduled for completion in September 976. This reservoir will reduce, but not eliminate, flooding in the Village of Itasca. The Kingery dike has been constructed on the east side of Salt Creek in the northern Village of Villa Park and it contains the 500-year flood. This dike is the eastern boundary of the floodway and is in extreme northern Villa Park. In addition, there is a local zoning ordinance in the Village of Villa Park which restricts development within 25

the floodplain. An Act in Regulation to the Rivers, Lakes, and Streams of the State of Illinois, approved June 0, 9, as amended (Illinois Revised Statutes, Chapter 9, 52 et seq, 975) authorizes the Department of Transportation to define floodplains and establish a permit procedure for regulating construction within such defined floodplains (Illinois Department of Transportation, 973). Ginger Creek Other than the local zoning ordinance, which restricts development within the floodplain, no flood protection methods have been adopted for Ginger Creek Watershed. Principal Flood Protection Measures for the Spring Brook Creek and West Branch Tributary Spring Brook Creek Spring Brook Creek and West Branch Tributary Spring Brook Creek flow through the Village of Bloomingdale and the village has two ordinances which pertain to floodwater management. The first, No. 73-9 (Village of Bloomingdale, 973), provides stormwater detention requirements for new commercial and residential developments. The other, No. 75-0 (Village of Bloomingdale, 975), regulates the interference with existing drainage channels. Detention basins as described in ordinance 73-9 exist and are currently planned for different areas in the village where future development is pending. No structural flood control measures have been built to relieve overbank flooding. Spring Road Tributary Other than the local zoning ordinance, which restricts development within the floodplain, no flood protection methods have been adopted for this watershed. Principal Flood Protection Measures for the West Branch DuPage River Watershed After the damaging floods in 948 and 950, the Illinois Division of Water Resources made flood control studies on the West Branch DuPage River and other streams. After the floods of 954 and 957, these studies were expanded and a report on the DuPage River completed in 962. This report recommended a program of channel improvement, some levee and flood wall construction, and a detention reservoir on the West Branch DuPage River upstream from the City of Naperville. These flood control measures were intended to control flood flows with an expected recurrence frequency of about 50 years. Subsequently, Fawell Dam was constructed approximately 0.25 mile upstream of U.S. Highway 34 (Ogden Avenue). This dam was designed with a flood control storage reservoir of 2,900 acre-feet, adequate for a 50-year flood. On September 8, 970, the Naperville City Council enacted Ordinance No. 336.70, which provides for regulation of Naperville s floodplains and drainage from new subdivisions. This ordinance stipulates that future construction in the floodplain shall be permitted 26

only in those areas outside the limits of a stream s floodway and outside the limits of floodwater detention or retention ponds and basins. In addition, all floodplain construction must be flood proofed to an elevation 2 feet above the established high-water elevation. Floodplain limits and high-water elevations defined by this ordinance are those indicated on the USGS Hydrologic Investigation Atlases (U.S. Department of the Interior, 965). As an additional storm runoff control measure, the City Council adopted Ordinance 72-74 on December, 972. This ordinance requires on-site storage of excess runoff for all developing areas. The volume of required storage is equal to the runoff from a 00-year frequency storm less the safe release capacity of the downstream outlet channel or storm sewer system. A report, Naperville- Northcentral Storm Drainage Report, was prepared for the City of Naperville by Lindley & Sons, Inc., in February 974 (Lindley and Sons, Inc., 974). This report examines existing storm drainage facilities, determines the causes of flooding, and recommends solutions. The recommendations of this report are in accordance with Naperville s Ordinance 72-74. Three detention basins have been constructed by the City of Naperville since 972, all of which have been designed to control runoff from the 00-year frequency rainfall. These basins are: the Jefferson School Basin, at the intersection of Washington Street and Iroquois Avenue; the County Commons Basin, just east of Huffman Street at School Street; and the Pembroke Greens Basin, just south of Cheshire Road between Charles Street and Richard Road. In addition, another basin is proposed for the grounds of North Central College, and plans call for the expansion of an existing quarry, referred to as the Chicago Avenue Basin, to 00-year storm capacity. At the request of the City of Naperville, the Chicago District, USACE, conducted a flood control study under the authority of Section 205 of the 948 Flood Control Act, as amended. A reconnaissance report to determine the Federal interest in continuing that study was scheduled for completion in 976. In addition, the USACE was authorized by Section 206 of Public Act 85-500 to investigate the feasibility of providing solutions to urban water damage problems caused by overbank flooding and poor drainage in northeastern Illinois and northwestern Indiana. The investigation of drainage problems was limited to sewer back-up caused by surcharging of drainage outlets by high river stages. The DuPage River Basin is included within the 2,600 square mile bi-state study area. The USACE initiated a study of the DuPage River Basin under this authority in the summer of 976. The West Branch DuPage River is the major cause of flooding in the Village of Hanover Park, Illinois, downstream from the Village of Schaumburg. Flood control works on the West Branch DuPage River in Hanover Park include extensive channel improvements and two retention basins. Retention Basin A will be located along the West Branch DuPage River near the Hanover Park- Schaumburg corporate boundary, about,500 feet west of Springingsguth Road. This basin will provide about 0 acre-feet of flood control storage, but will not affect flood elevations on the West Branch DuPage River in Schaumburg. 27

Flood protection works planned by local and state agencies, and the Metropolitan Sanitary District are under construction on the West Branch DuPage River at Hanover Park, about 4 miles upstream from West Chicago. These works, consisting of channel improvements and detention ponds, will have no significant effect on flood peak discharges at West Chicago. The USACE was authorized by Section 206 of the Federal Public Act 85-500 to investigate the feasibility of providing solutions to urban water damage problems caused by overbank flooding and poor drainage in northeastern Illinois and northwestern Indiana. The investigation of drainage problems will be limited to severe back-up caused by surcharging of drainage outlets by high river stages. The DuPage River basin is included within the 2,600 square mile bi-state study area. The Chicago District of the USACE initiated a study of the DuPage River basin under this authority in the summer of 976. At present, there are no significant flood-control structures built or planned on the study streams at West Chicago. The City of West Chicago has mapped the flood hazard areas and, by powers vested in the city building inspector by various city building ordinances, regulates construction thereby requiring that first-floor levels be elevated to a point 3 feet above the flood of record. Three dams have been built on the West Branch DuPage River. These are Warrenville Grove Dam, McDowell Forest Preserve Dam, and Fawell Dam. Warrenville Grove and McDowell Forest Preserve Dams are low-flow dams with no storage capacity. The other dam, Fawell Dam, lies north of Naperville and was constructed as a flood control dam. There are no new major flood control projects proposed for the West Branch DuPage River for the near future. Klein Creek There are no flood protection works existing or planned on streams within the Klein Creek Watershed. Unnamed Creek South of Foxcroft Road and Unnamed Creek South of 87 th Street Earthen dikes with.0-foot diameter culverts are located along each of the two unnamed tributaries to the West Branch DuPage River. These dikes were placed by private interests and cause an open field just southwest of the intersection of 87 th Street and Washington Street to act as a detention pond. Because of their questionable construction, however, these dikes cannot be relied upon as flood control structures. Winfield Creek Development of floodplains within the City of Wheaton is currently regulated by Chapter 2.5 of the Wheaton City Code. The problem of overbank flooding along Winfield Creek was recently studied for the City of Wheaton by the engineering firm of Baxter and Woodman, Inc. As a result of these studies (Baxter and Woodman, Inc., 975; Baxter and Woodman, Inc., 976), several suggestions 28

were made to alleviate the flooding situation along the stream. These include construction of berms around properties near Gary Avenue, reconstruction of several culverts, debris clearance, and construction of a retention pond. 3.0 ENGINEERING METHODS For the flooding source studied in detail in the county, standard hydrologic and hydraulic study methods were used to determine the flood hazard data required for this FIS. Flood events of a magnitude which are expected to be equaled or exceeded once on the average during any 0-, 50-, 00-, or 500-year period (recurrence interval) have been selected as having special significance for floodplain management and for flood insurance rates. These events, commonly termed the 0-, 50-, 00-, and 500-year floods, have a 0-, 2-, -, and 0.2-percent chance, respectively, of being equaled or exceeded during any year. Although the recurrence interval represents the long term average period between floods of a specific magnitude, rare floods could occur at short intervals or even within the same year. The risk of experiencing a rare flood increases when periods greater than year are considered. For example, the risk of having a flood which equals or exceeds the 00-year flood (-percent chance of annual exceedence) in any 50-year period is approximately 40 percent (4 in 0), and, for any 90-year period, the risk increases to approximately 60 percent (6 in 0). The analyses reported herein reflect flooding potentials based on conditions existing in the county at the time of completion of this FIS. Maps and flood elevations will be amended periodically to reflect future changes. 3. Hydrologic Analyses Hydrologic analyses were carried out to establish the peak discharge frequency relationships for each flooding source studied in detail affecting the county. Precountywide Analysis Each jurisdiction within DuPage County has a previously printed FIS report. The hydrologic analyses described in these reports have been compiled and are summarized below. Discharge-frequency data for East Branch DuPage River, West Branch DuPage River, mouth of Lacey Creek, Klein Creek, Klein Creek Tributary No. 2 were developed through the use of the Chicago Metropolitan Study, DuPage River Basin performed by the USACE s Hydrologic Engineering Center (USACE, 974). In the Chicago study, the DuPage River Basin above Shorewood, Illinois, was divided into 20 subareas and a generalized HEC- rainfall-runoff computer model was calibrated for the basin (USACE, 973). Using 24-hour rainfall data obtained from Weather Bureau Technical Paper No. 40, one-hour values, in critical order, were entered into the HEC- model of the DuPage River Basin to determine the 0-year, 50-year, and 00-year peak discharges (U.S. Department of Commerce, 963). 29

The 500-year peak discharge was determined from a linear extrapolation of a logprobability curve for the 0-, 50-, and 00-year values. Hydrologic computations for the Village of Glen Ellyn Links storm retention system, as well as other areas in the village which experience shallow flooding, were based on the SCS Technical Release No. 55 (U.S. Department of Agriculture, 975). The drainage basin of the Village Links system was first subdivided into those areas which drain directly into the golf course ponds, and those which first drain into other ponds and eventually discharge into the golf course ponds through storm sewers. For all areas, storage volumes and release rates applicable to a 00-year flood were then determined. The discharge rate available to direct runoff to the golf course was reduced to account for release rates of upstream ponding areas and storm sewers. The final required detention volume and corresponding 00-year flood elevation for the golf course was then determined. Discharges for the 0-year, 50-year, and 00-year floods for the Des Plaines River, East Branch Tributary No., East Branch Tributary No. 2, East Branch Tributary No. 4, East Branch Tributary No. 5, East Branch Tributary No. 7, West Branch Tributary No., West Branch Tributary No. 2, West Branch Tributary No. 3, West Branch Tributary No. 4, West Branch Tributary No. 5, West Branch Tributary No. 6, West Branch Tributary No. 7, Brewster Creek, Ferry Creek, Ferry Creek Tributary No., Klein Creek, Klein Creek Tributary No., Klein Creek Tributary No. 3, Kress Creek, Unnamed Tributary to Kress Creek, Lacey Creek, Meacham Creek, Norton Creek Tributary, Prentiss Creek, St. Joseph Creek, Salt Creek, Sawmill Creek, Sawmill Creek Tributary No., Sawmill Creek Tributary No. 3, Wards Creek, Winfield Creek, Ginger Creek, Crabtree Creek, Unnamed Creek North of 22 nd Street, Waubansee Creek, Winding Creek, Westwood Creek, Sugar Creek, Spring Brook, Spring Brook No., Spring Brook No. 2, Tributary A, Tributary B, Armitage Ditch, and 63 rd Street Ditch studied in detail and for the 0-year and 00-year events for streams studied by the limited detail method were computed using the log-pearson Type III method (U.S. Department of Commerce, 976) for gaged streams and regional equations for ungaged streams (U.S. Department of the Interior, 973; State of Illinois, 973). The 500-year flood discharges for streams studied in detail were estimated by straight line extrapolation. The USGS stream gages used for the hydrologic analyses for the streams studied in detail in the Unincorporated Areas of DuPage County, Illinois, are presented below: USGS Stream Gages USGS Drainage Area Record Flooding Source and Location Gage Number (sq. miles) (years) Brewster Creek at Valleyview 0555030 4.0 4 Des Plaines River at Lockport 05534050 700.0 7 East Branch DuPage River at Lisle 05540230 58.3 2 30

USGS Stream Gages - continued USGS Drainage Area Record Flooding Source and Location Gage Number (sq. miles) (years) East Branch DuPage River at Naperville 05540260 8.0 West Branch DuPage River at Naperville 0554030 23.0 West Branch DuPage River near Warrenville 05540095 90.4 0 Ferry Creek at Warrenville 055400 4.27 5 Klein Creek at Carol Stream 05539950 8.8 5 Kress Creek at West Chicago 05540050 0.0 5 Norton Creek near Wayne 0555050 7.35 5 Prentiss Creek near Lisle 05540240 6.48 5 St. Joseph Creek at Lisle 05540200.8 5 Salt Creek at Elmhurst 0553300 90.6 5 Salt Creek at Oak Brook 0553380 00.0 5 Sawmill Creek near Lemont 05533400 3.0 5 Spring Brook No. near Warrenville 05540090 6.0 5 Winfield Creek at Winfield 05540020 6.95 5 The results of the hydrologic analyses were submitted to the Illinois State Water Survey for review. The 00-year flood discharges computed for the streams studied in detail and the streams studied by limited detail in the unincorporated areas of DuPage County were approved by the SWS and were certified by the DWR. Hydrologic analyses were made to establish the peak discharge-frequency relationships for floods of selected recurrence intervals on Salt and Westwood Creeks in Addison. Base flood elevations and flows for Tributary No. 2 were determined using a continuous simulation approach. Historical series of simulated flood elevations and flow are computed using dynamic hydrologic and hydraulic models. Then, a statistical procedure was used to determine flow and stage quantiles at locations of interest along the stream channel. Peak flows for the 0-, 50-, 00-, and 500-year floods were determined for Bronswood Cemetery Tributary, Ginger Creek, and Spring Road Tributary by the ISWS in accordance with the USGS report Technique for Estimating Magnitude and Frequency of Floods in Illinois (U.S. Department of the Interior, 977). This report described a technique for estimating flood magnitudes at recurrence intervals ranging from 2 to 500 years, for unregulated rural streams in Illinois, having drainage areas ranging from 0.002 to 0,000 square miles. The 3

independent variables, drainage area, slope, rainfall intensity, and an aerial factor were used to define the flood-frequency relationship. In addition, a provision included allowed for weighting the estimate to an existing gage record. The discharges used in this study were determined by the SCS and the ISWS and were approved by the DOWR. For Crabtree Creek, flood peak discharges were computed using the multiple regression equations stated in Magnitude and Frequency of Floods in Illinois (Illinois Department of Transportation, 973). Discharges for the 500-year floods were determined by straight-line extrapolation of a log-probability curve of flood discharges computed for frequencies up to 00 years. For Cress Creek and Winding Creek, synthetic frequency-discharge curves were derived using regional statistics developed in the Chicago study. These discharges assume zero skew. Discharges for the 500-year floods of all streams were determined by linear extrapolation of a log probability curve of flood discharges computed for frequencies of up to 00 years. For Devon Avenue Tributary, and Meacham Creek, a gauging station on Salt Creek located about 20 miles downstream of Itasca was one source of data for defining discharge-frequency relationships. This gage has been operated since 945. A gauging station on Meacham Creek at Medinah in the northwest part of Itasca was used in defining discharge-frequency relationships. This gage was operated from 953-972. Values of the 0-, 50-, and 00-year peak discharges were obtained from a log-pearson Type III distribution of annual peak flow data (U.S. Water Resources Council Hydrologic Committee, 976). However, much channel work has been performed on Salt Creek and rapid urbanization of the watershed has occurred during the operation period of the stream gages, especially in the past 0 years. The effect of these changes has not been adequately recorded. Water from large floods has overflowed into a quarry about 0 miles upstream of the gage. Therefore, peak discharge-drainage area relationships were developed from a combination of historic flood data and unit hydrograph rainfall-runoff relationships. Flood routing was done with the SCS- TR-20 Project Formulation Computer Program (U.S. Department of Agriculture, 974). Linear regression analysis was used to determine the 0-, 50-, and 00- year peak discharges as a function of the drainage area at any given cross section. The 500-year peak discharge was determined by a log-log extrapolation of peak discharges computed for frequencies up to 00 years. The peak discharges obtained were substantiated by regional flood flow equations for northeastern Illinois. Discharges for the 500-year flood for East Branch DuPage River, North Branch St. Joseph Creek, South Branch St. Joseph Creek, and Lacey Creek were determined by linear extrapolation of a log-probability graph of flood discharges computed for frequencies up to 00 years. Peak discharges for the upstream reaches of Lacey Creek were obtained by applying the square root of the drainage area ratio method to discharge values obtained from the HEC- computer model. 32

This method consists of calculating upstream discharges from a known downstream station by multiplying the discharge values from that downstream station by the square root of the ratio of the drainage area of the upstream station in question to the drainage area of the downstream station. Harza prepared hydrologic analyses using the State Standard Method, and discharges for 0- and 00-year floods were estimated for Flagg Creek using the regional urbanized equations for Illinois (U.S. Department of the Interior, 974). The 00-year discharges calculated by Harza were sent to the Illinois SWS for review. The discharges were approved by the SWS and certified by the DOWR. Data are located in a repository of flood-related data administered by the SWS. For each cross section of Flagg Creek, discharges for the 0- and 00-year floods were plotted on log-normal probability paper. The 50- and 500-year flood discharges were estimated by straight-line interpolation and extrapolation, respectively. The 500-year flood discharge is less reliable than the others because the period of record for discharge gages used to develop the regional urban equations is about 30 years. The hydrologic analysis of Klein Creek Tributary No. 3 was directly transferred from the DuPage County FIS (FEMA, 982). Discharges for the 0-year and 00-year floods of Klein Creek Tributary No. 3 were computed using the log- Pearson Type III method (U.S. Water Resources Council, 976). Discharges for the 500-year floods of all streams were determined by linear extrapolation of a log-probability graph of flood discharges computed for frequencies up to 00 years. Kress Creek is within sub area 6 of the Chicago Metro Study. Peak flows for this sub area, previously derived by the Chicago District, were utilized to derive peak flood flows on Kress Creek and the Unnamed Tributary to Kress Creek. A discharge-frequency relationship was developed for Kress Creek at State Highway 38, and peak flows for Kress Creek at the mouth were obtained by applying the square root of the drainage area ratio. The frequency-discharge drainage area relationships for the streams studied in detail in the community are presented in Table, Summary of Discharges. The peak discharge for a portion of the headwater area of Kress Creek studied by approximate methods was determined from a regional curve which indicated the 00-year peak discharge as a function of average streambed slope. This curve was determined by solving and plotting solutions to the multiple regression equation adopted by the State of Illinois for several streams within DuPage County (State of Illinois, 973). There are no stream flow recording gages on Norton Creek. In order to simulate flows for Norton Creek and Norton Creek Tributary, a regional frequency analysis has been completed for the gages in the vicinity of the Norton Creek drainage basin. Thirteen USGS gages with one to 20 years of records in the DuPage River drainage basin provided data for the regional frequency analysis. To enable the regional frequency model to more accurately predict the flows for a small basin, the DuPage data have been augmented by records from gages with small drainage 33

areas. Also included in the study are six gages from DuPage County basin having drainage areas of less than 20.0 square miles and six gages from basins within the region having drainage areas less than 2.0 square miles. The technique for a regional frequency analysis outlined in Bulletin No. 7 from the U.S. Water Resources Council (U.S. Water Resources Council, 976) has been used to calculate the discharges for Norton Creek and Norton Creek Tributary. The discharges for Prentiss Creek were derived from a regional frequency analysis using two Illinois Division of Water Resources stage recording gages located on the East Branch DuPage River, and five damage index stations used in the above Chicago Metro Study. Of these damage index stations, three were located along St. Joseph Creek, and one each along the East Branch DuPage River and Armitage Ditch. The analysis of the two Division of Water Resources gages, no. D W-C-3 at Naperville in Will County and No. D W-C-4 near Lisle in DuPage County, with individual recording periods of 4 and 5 years, respectively, followed the standard log-pearson Type III method as outlined by the Water Resources Council (U.S. Water Resources Council, 967). For the damage index stations, synthetic frequency-discharge curves were derived using regionalized statistics developed in the Chicago Metro Study. Flood peak discharges were obtained from regional drainage area-peak discharge curves computed from the results of the above gage and station analyses. Discharges for the 500-year floods were determined by straight-line extrapolation of a logprobability curve of flood discharges computed for frequencies up to 00 years. For Rott Creek and St. Joseph Creek, synthetic frequency-discharge curves were derived for three stations used in the Chicago Metropolitan study using regionalized statistics developed in that study and assuming zero skew. Discharges for the 0-, 50-, 00-, and 500-year floods on St. Joseph Creek in the Village of Westmont were derived by extrapolation of discharge-drainage area relationship for the creek in Downers Grove. Discharges for Tributaries, 2, and 3 in Lisle were derived from DWR multiple regression equations (State of Illinois, 973). Discharges for Saint Procopius Creek were computed by using the square root of the drainage area ratio applied to the results for Lacey Creek. The peak discharges for Tributary 4 were derived using the square root of drainage area ratio with Prentiss Creek applied to peak discharges for the East Branch DuPage River. Discharges for the 500-year floods of all streams were determined by linear extrapolation of a log-probability graph plotted for calculated peak discharges. Flood frequency curves for Salt Creek and Westwood Creek were prepared for this study and are based on discharges calculated by the SCS. The SCS has completed, recently, a comprehensive flood management study of the Salt Creek watershed as part of the Chicago Metropolitan Area River Basin Plan. That study included detailed watershed modeling utilizing the SCS watershed model TR-20 (U.S. Department of Agriculture, 974). It is an advanced hydrologic model which accurately simulates the historical flood stage- and discharge-hydrographs. The model was used for a regional analysis of the entire watershed. The model 34

included consideration of the Busse Woods and Kingery Detention Reservoirs. Elevation-capacity and outlet rating data were included in the model and were utilized in routing the hydrographs through the watershed. Estimates of flood discharge resulting from that study are the most current, and the 00-year discharges have been approved by the State of Illinois for use in the state s floodplain regulation program. Data are located in the Illinois State Water Survey Floodplain Repository. Harza prepared additional hydrologic analyses which provided an independent review of the suitability of the results in concurrence with FIA s guidelines. Discharges for the 00-, 50-, and 0-year floods were computed for Salt Creek and Westwood Creek by Harza using regional flood frequency equations for Illinois (Illinois Department of Transportation, 979). The discharges determined for Salt Creek are higher than the historic discharges because they are based on conditions projected to exist in the year 2000. The Salt Creek discharges decrease moving downstream as a result of overbank storage. The calculated unit flood discharges were compared to those for neighboring watersheds. This review by Harza established that the flood discharges computed by the SCS using their TR-20 program and certified by the State of Illinois are suitable for use in this FIS. The SCS discharges for the 0-, 25-, and 00-year floods for the two streams were plotted on log-normal probability paper. The 50- and 500-year flood discharges were estimated by straight-line interpolation and extrapolation, respectively. A frequency-discharge, drainage area table for the streams investigated in Addison is shown in Table. The flood discharges of specified return periods were compared with those calculated by the SCS using the TR-20 program for Sawmill Creek and East Branch Sawmill Creek. The SCS discharges for Sawmill Creek were found suitable, but the discharges for East Branch Sawmill Creek were found to be lower than the acceptable range of discharges calculated using the State Standard Method. Therefore, the discharges submitted to the SWS for East Branch Sawmill Creek are Harza values. All of the discharges for the detailed study areas were sent to the SWS for review and approval, and the 00-year discharges were certified by the DOWR for use in its floodplain regulation program. Data are located in a repository of flood-related data administered by the SWS. Discharges for the 2-, 5-, 0-, 25-, and 00-year floods were available from the SCS TR-20 model of Sawmill Creek (U.S. Department of Agriculture, 965). Discharges for the 0- and 00-year floods on East Branch Sawmill Creek and West Branch Sawmill Creek in the City of Darien were calculated by Harza using regional flood frequency equations (Illinois Department of Transportation, Magnitude and Frequency of Floods in Illinois, 973). Data for the three detailed study streams were plotted separately on log-normal probability paper, and the 50- and 500-year floods were estimated by straight-line interpolation and extrapolation, respectively. The 500-year flood discharge estimates are less reliable than the others because: ) the precipitation-frequency relationship, required for the TR- 20 program, is not well defined for this rare event, and 2) the average period of record for stream gages used to derive the regional equations is about 30 years. 35

Peak flows for the 0-, 50-, 00-, and 500-year floods on Spring Brook Creek and the West Branch Tributary Spring Brook Creek were computed using the TR-20 computer program (U.S. Department of Agriculture, 965) with data furnished by the SCS. Discharges for this study were coordinated with the ISWS and approved by the IDWR. The discharges for St. Joseph Creek Tributary were derived using the State Standard Method. Discharges for the 0- and 00-year floods were computed using regional equations for Illinois (U.S. Department of the Interior, 974). Hydrologic and hydraulic analysis of the detention ponds on the stream showed that their effect on floods greater than or equal to the 0-year event is minimal. Therefore, no adjustments were applied to the discharges developed from the regional equations. Discharges for the 0- and 00-year floods were plotted on log-normal probability paper. The 50- and 500-year flood discharges were estimated by straight line interpolation and extrapolation, respectively. The 00- year discharges estimated for the two detailed study streams were sent to the SWS for review. The discharges were approved by the SWS and certified by the DOWR. Data are located in a repository of flood-related data administered by the SWS. Peak flows for the 0-, 50-, 00-, and 500-year floods on Sugar Creek were computed using the Soil Conservation Service (SCS) Technical Release No. 20 (U.S. Department of Agriculture, 965). Peak flows for the 0-, 50-, 00-, and 500-year floods on Sugar Creek Tributary A were computed by the Illinois State Water Survey in accordance with the USGS report, Technique for Estimating Magnitude and Frequency of Floods in Illinois (U.S. Department of the Interior, 977). This report describes a technique for estimating flood magnitudes at recurrence intervals ranging from 2 to 500 years, for unregulated rural streams in Illinois, having drainage areas ranging from 0.002 to 0,000 square miles. The independent variables drainage area, slope, rainfall intensity, and an aerial factor are used to define the flood frequency relationship. In addition, a provision included allows for weighting the estimate to an existing gage record. The discharges used in this study were coordinated with the Illinois State Water Survey and approved by the Illinois Division of Water Resources. The DuPage County Department of Development and Environmental Concerns has been working with the Northeastern Illinois Planning Commission (NIPC) to perform the regional hydrologic analysis for various watersheds since early 980. A continuous hydrologic model, Hydrologic Simulation Program, FORTRAN (HSPF), was used to simulate the hydrologic characteristics of the Tributary No. 2 watershed. HSPF uses a Watershed Data Management (WDM) file for storing input and output data. Hydrologic modeling for the Tributary No. 2 watershed is documented in Hydraulic Evaluation of HSPF Model for East Branch DuPage River Watershed (Price and Chang, 200). This document describes the development and calibration of an HSPF model used to represent runoff from land 36

covers throughout the East Branch watershed. The calibrated HSPF model generates unit runoff in inches per hour for six typical land covers. The land covers were developed for soil and vegetative conditions typically found in DuPage County. These land covers represent impervious area, flat medium and steep-sloped grassed areas, forest and agricultural land. HSPF was regionally calibrated to five stream flow gages in the three primary watersheds in DuPage County (Salt Creek, East Branch of the DuPage River, and West Branch of the DuPage River) and then verified using a separate period of record and additional stream flow gates. Discharges for the Unnamed Creek south of Foxcroft Road and Unnamed Creek south of 87 th Street in the City of Naperville two unnamed tributaries to the West Branch DuPage River were adjusted to reflect interbasin flow between the two streams. The Hydrologic Investigations Atlas for the Normantown quadrangle indicates that interbasin flow occurred during the October 954 flood (U.S. Department of the Interior, 965). Discharges for the two streams were adjusted on a trial-and-error basis until corresponding water-surface elevations in the area of interbasin flow were within 0.5 foot of each other, reflecting gently sloping sheet flow between the two streams. As a result, discharges for the unnamed creek in the area south of 87 th Street were decreased, while those for the creek in the area south of Foxcroft Road were increased. For the Waubansee Creek, estimates of the 0-, 50-, and 00-year floods were plotted on log-normal probability paper, and the 500-year flood discharges were estimated by straight line extrapolation. The 500-year flood discharge is less reliable than the others because the average period of record for stream gages used to prepare the regional equations is approximately 30 years. The reliability of the 00-year flood discharge is between those of the 50- and 500-year floods. The 00-year discharge value that was used in the 978 FIS for Waubansee Creek was adopted for the May 5, 986, restudy. The analysis did not include the 0-, 50-, or 500-year frequency flood events. To allow for zone calculations, the 0- year flood elevation was generated by approximate methods. Frequency-discharge data for Winfield Creek were developed through the use of the Chicago Metropolitan Study, DuPage River Basin (USACE, 973) performed by the USACE s Hydrologic Engineering Center. In the Chicago Metro Study, the DuPage River basin above Shorewood, Illinois, was divided into 29 subareas and a generalized HEC- rainfall-runoff computer model was calibrated for the basin (USACE, 973). One-hour increments of a 24-hour storm rainfall, obtained from the U.S. Weather Bureau Technical Paper No. 40 (U.S. Department of Commerce, 96), were entered into the HEC- model of the basin to obtain the 0-, 50-, and 00-year flood peak discharges. Point rainfall-frequency curves derived from Technical Paper No. 40 were extrapolated to obtain a 500-year rainfall distribution, from which the 500-year flood peak discharges were computed. Since the discharges computed by this method applied to the total subarea tributary to the West Branch DuPage River in which each stream was located, the corresponding subarea discharges were reduced by the square root of 37

the drainage area ratio for each stream. Discharges for Winfield Creek below Main Street, computed by the above methods, were decreased following a reservoir routing analysis for the area between Chicago and North Western railroad bridges and Main Street. (A reservoir routing analysis was used because of the large ponding area that is very flat.) Frequency-discharge data for the Unnamed Tributary North of 22 nd Street were developed through the use of the SCS Urban Hydrology for Small Watersheds, Technical Release No. 55 (U.S. Department of Agriculture, 975). This method was considered the most appropriate because the drainage areas were small, and the method accounted for the diversity and irregularity of the land use within the basin. Harza prepared the hydrologic analysis for the 59 th Street Ditch. Discharges for the 2- and 00-year floods for this stream were computed using the Illinois State Standard Method Urbanized Equations (U.S. Department of the Interior, 974). The 00-year discharges were sent to the SWS for review. The discharges were approved by the SWS and certified by the DOWR. These data are located in a repository of flood-related data administered by the SWS. For each cross section, discharges for the 2- and 00-year floods were plotted on log-normal probability paper. The 0-, 50-, and 500-year flood discharges were estimated by straight line interpolation and extrapolation. Discharges for the 0-, 50-, and 00-year floods for the 63 rd Street Ditch were determined using regional equations developed by the Illinois SWS. The principal factors considered in this method were soil types, land uses, watershed slope, channel slope and dimensions, and rainfall distributions (Illinois Department of Transportation, Magnitude and Frequency of Floods in Illinois, 973). The discharges were adjusted using factors recommended by the SWS which were developed from data for the USGS gage on Flagg Creek at Willow Springs, Illinois. The 00-year flood discharges for 63 rd Street Ditch and East Branch Sawmill Creek in Willowbrook were sent to the SWS for review. These discharges were approved by the SWS and certified by the DOWR for use in the State s floodplain regulation program. Data are located in the Illinois Floodplain Repository which is administered by the SWS. Discharges for the 0-, 50-, 00-, and 500-year floods of each flooding source studied in detail in the community are shown in Table. Discharges for the 0-, 50-, and 00-year floods on 79 th Street Ditch and Plainfield Road Ditch were determined by Harza using regional flood-frequency equations. The parameters used were channel slope, drainage area, and the percent of urbanization and nearby gage records using methods recommended by the Illinois SWS. These methods were determined by the log-pearson Type III analysis and the regional discharge equation at gage location (Baranecki, Vigilio, and Associates, 977). The adjustment coefficients were developed from data for the USGS gage (No. 05533000, established in 95), located at the 6.2-mile marker on Flagg Creek at Willow Springs, Illinois. The 00-year discharges for 38

the streams were sent to the Illinois SWS for review. They were approved by the Illinois SWS and certified by the Illinois DWR for use in the state s floodplain regulation program (Des Plaines River Watershed Steering Committee, 975). Data are located in the State Floodplain Repository administered by the Illinois SWS. The flood discharges on Plainfield Road Ditch are much higher than the discharges of 79 th Street Ditch because the slope of Plainfield Road Ditch is 30 percent greater than the slope of 79 th Street Ditch, thereby increasing the rate of runoff. A summary of the drainage area-peak discharge relationships for the portions of the streams studied by detailed methods is shown in Table 3, Summary of Discharges. TABLE 3 - SUMMARY OF DISCHARGES FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR ADDISON CREEK At downstream corporate Limits 0.82 90 522 96 * ADDISON CREEK TRIBUTARY NO. At George Street Reservoir 0.93 54 96 22 85 ADDISON CREEK TRIBUTARY NO. 2 At York Road.8 56 88 06 46 At Church Road 0.33 28 44 50 68 ADDISON CREEK TRIBUTARY NO. 3 Approximately 300 feet Downstream of George Street.20 50 62 86 5 At Church Road 0.23 8 28 34 43 ARMITAGE CREEK At mouth 2. 320 550 75,420 Above confluence with Armitage Fork 0.8 95 325 435 865 At Ardmore Avenue 0.4 40 235 305 605 Above Placid Avenue 0.2 60 35 225 540 *Data not available 39

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR ARMITAGE FORK At mouth 0.7 85 35 45 820 BENSENVILLE DITCH Just downstream of Garden Avenue.82 367 663 774 * Just downstream of York Road.56 296 527 60 * Just downstream of Mason Street.32 283 50 564 * At Church Street.07 246 470 520 * BREWSTER CREEK At river mile 4.6 2.90 94 9 393 BRIARWOOD DITCH Approximately 360 feet upstream of confluence with Ginger Creek * * * 339 * Approximately 950 feet upstream of confluence with Ginger Creek * * * 447 * Approximately 80 feet downstream of Briarwood Central Road * * * 32 * BRONSWOOD CEMETERY TRIBUTARY At confluence with Ginger Creek 02 2,72 3,277 3,698 4,488 At Roosevelt Road 95 2,87 3,294 3,698 4,488 At confluence with Salt Creek.25 298 408 448 526 East of Adams Road 0.95 255 350 384 45 East of State Route 83 0.3 48 203 223 262 CRABTREE CREEK Within Village of Woodridge corporate limits.45 325 575 740,430 CRESS CREEK At mouth.90 95 325 385 560 *Data not available 40

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR DES PLAINES RIVER At river mile 26.75 684 6,060 7,800 9,000 0,000 DEVON AVENUE TRIBUTARY At lower corporate limit for the Village of Itasca.20 30 200 240 320 Approximately 00 feet upstream of Pierce Road 0.80 05 65 200 270 EAST BRANCH DUPAGE RIVER At Mile 30.6 80. 2,000 2,90 3,375 4,700 Just downstream of Crabtree Creek 75.3,850 2,630 3,080 4,270 At Hobson Road bridge 7.,840 2,600 3,05 4,75 At Maple Avenue 58.3,80 2,50 2,900 3,880 At East-West Tollway 40.,370,850 2,200 2,890 At Butterfield Road 27.2,00,325,630 2,090 At Glen Ellyn Sewage Disposal Plant 22.9 885,50,435,820 At St. Charles Road 4.2 60 760 990,220 Above confluence with Armitage Creek 6.4 280 330 350 40 EAST BRANCH SAWMILL CREEK At 79 th Street 2.0 253 40 48 690 At 75 th Street 0.99 78 290 340 480 At Elm Street 0.55 23 200 235 332 At Janet Road 0.32 89 40 70 239 At Rodger Road 0.24 75 20 40 200 At 68 th Street 0.20 65 03 20 70 EAST BRANCH TRIBUTARY NO. At mouth 0.44 85 55 20 330 EAST BRANCH TRIBUTARY NO. 2 At mouth 0.97 80 35 420 620 4

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR EAST BRANCH DUPAGE RIVER TRIBUTARY 3 At the mouth 0.34 30 245 325 600 Above Winchester Avenue 0.4 85 55 20 385 EAST BRANCH TRIBUTARY NO. 4 At Leask Lane 4.34 455 730 870,200 At mouth 2.60 370 485 550 750 EAST BRANCH TRIBUTARY NO. 5 At mouth 4.95 455 730 870,200 EAST BRANCH TRIBUTARY NO. 7 At mouth 0.7 80 330 425 650 FERRY CREEK At East-West Tollway 8.60 380 540 65 805 FERRY CREEK TRIBUTARY NO. At mouth 2.39 50 265 300 390 FLAGG CREEK At mouth 8.,660 2,650 3,80 4,500 Approximately 600 feet upstream of 79 th Street Ditch 5.3,420 2,300 2,720 3,850 At State Route 83.40 202 32 380 530 At Eastern Avenue 0.40 0 60 90 265 GINGER CREEK Downstream of Jorie Boulevard * * *,256 * Approximately 250 feet Upstream of Gabion Wier * * *,275 * Downstream of Route 83 * * *,277 * Downstream of Briarwood Lake * * *,27 * *Data not available 42

TABLE 2 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR GINGER CREEK (continued) Upstream of confluence With Briarwood Ditch * * * 742 * Downstream of Regent Drive * * * 708 * Upstream of Regent Drive * * * 695 * Upstream of Sheet Pile Weir * * * 643 * Approximately 300 feet upstream of Sheet Pile Weir * * * 63 * Approximately 300 feet Downstream of confluence With Trinity Lakes 2 Tributary * * * 566 * Downstream of Midwest Road * * * 554 * Upstream of Baybrook Lane * * * 405 * Downstream of Meyers Road * * * 34 * Upstream of Baybrook (West) * * * 75 * HERITAGE OAKS TRIBUTARY Approximately 680 feet upstream of confluence with Ginger Creek * * * 60 * KLEIN CREEK Downstream of Thunderbird Trail in the Village of Carol Stream 6.37 445 592 655 947 Approximately,000 feet upstream of Dam A in the Village of Carol Stream 4.90 400 542 69 87 *Data not available 43

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR KLEIN CREEK TRIBUTARY NO. At mouth.2 33 60 95 240 KLEIN CREEK TRIBUTARY NO. 2 At confluence with Klein Creek.22 220 300 355 55 KLEIN CREEK TRIBUTARY NO. 3 At mouth 0.78 40 * 208 * KRESS CREEK Mouth at West Branch DuPage River 8.3 760,060,70,470 At mouth 6.5 760,060,70,470 At Town Road 4.8 655 95,000,270 Approximately.4 miles downstream of Lies Road 2.3 580 80 890,25 At Roosevelt Road (State Highway 38) 0. 50 70 780 985 At Indian Boundary Road 5.40 365 50 560 705 At Hawthorne Lane 4.20 330 460 505 635 At river mile 7.66.46 40 45 52 63 LACEY CREEK At mouth 4.80 450 720 860,80 LOMBARD TRIBUTARY Downstream of Royal Drive * * * 475 * Upstream of Royal Drive * * * 475 * MAYS LAKE TRIBUTARY Upstream of 3 st Street * * * 70 * Approximately 250 feet Upstream of 3 st Street * * * 67 * MEACHAM CREEK At Lake Kadijah 5.0 92 283 325 426 At Thorndale Avenue 3.60 5 95 235 328 *Data not available 44

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR MIDWEST CLUB TRIBUTARY Approximately 450 feet upstream of confluence with Ginger Creek * * * 43 * Approximately,000 feet upstream of confluence with Ginger Creek * * * 24 * Approximately,500 feet upstream of confluence with Ginger Creek * * * 06 * Approximately 200 feet downstream of 3 st Street * * * 75 * NORTH BRANCH ST. JOSEPH CREEK At confluence with St. Joseph Creek 2.05 250 395 465 650 NORTH UNNAMED CREEK At York Road 3.54 77,264,576 2,479 At downstream end of culvert 0.80 98 345 439 688 NORTON CREEK At Dunham Road 4.82 438 665 77,038 Upstream of the confluence of Norton Creek Tributary 3.46 365 555 645 870 NORTON CREEK TRIBUTARY At mouth.78 365 555 645 870 PLAINFIELD ROAD DITCH At mouth.0 97 30 367 50 At County Line Road.00 4 223 262 365 PRENTISS CREEK At mouth 6.60 540 850,020,40 At 63 rd Street bridge 3.97 420 665 795,00 *Data not available 45

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR ROTT CREEK At mouth 5.06 405 640 745,025 At Yackley Avenue 4.94 395 620 725 995 Below Old Tavern Road 3.9 275 430 505 695 Below East-West Tollway 3.44 88 269 306 382 SALT CREEK At York Road 2 2,58 3,258 3,650 4,427 At 3 st Street 06 2,62 3,258 3,655 4,434 At confluence of Ginger Creek 02 2,72 3,277 3,680 4,450 At confluence of Spring Road Tributary 99.2 2,86 3,290 3,696 4,480 At confluence of Sugar Creek 95.0 2,87 3,30 3,698 4,495 At St. Charles Road 90.7,9 2,724 3,7 4,520 At Chicago and Northeastern Railway 88.8,95 2,730 3,78 4,530 At State Route 83 88.0 2,90 3,306 3,70 4,502 Approximately 0.67 mile downstream of Interstate 90 85.7 2,263 3,34 3,846 5,224 Approximately 250 feet downstream of Fullerton Avenue 85.7 2,248 3,308 3,803 5,55 At Fullerton Avenue 84.0 2,247 3,390 3,803 4,65 Approximately 4,800 feet upstream of Lake Street 82.7 2,267 3,350 3,857 5,240 Approximately 660 feet upstream of Elizabeth Drive in City of Wood Dale 73 2,20 3,00 3,524 4,500 Approximately 528 feet downstream of Irving Park Road 7.4 2,0 3,090 3,502 4,490 Approximately 792 feet upstream of Chicago, Milwaukee, St. Paul and Pacific Railroad 70.86 2,0 3,070 3,484 4,470 Upper corporate limit for City of Wood Dale 54.4,650 2,30 2,590 3,260 At Plum Grove Road 0.8 522 792 93,225 46

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR SAWMILL CREEK Approximately 80 feet upstream of Bluff Road 3.0,363 * 2,588 * At 79 th Street.24 294 476 566 800 At 75 th Street 0.97 243 394 467 660 SAWMILL CREEK TRIBUTARY At river mile 0.23 2.33 324 * 67 * SAWMILL CREEK TRIBUTARY 3 At mouth.4 24 427 559 960 SOUTH BRANCH ST. JOSEPH CREEK At confluence with St. Joseph Creek 0.75 80 285 335 465 SOUTH UNNAMED CREEK At York Road.68 426 736 95,42 At Fairway Drive.2 202 346 429 693 SPRING BROOK CREEK Approximately,76 feet upstream of Route 53 2.0 642,040,264,800 At mouth 4.4 493 880,090,650 At mile 2.97 3.30 350 480 555 800 At Aurora Way 2.78 305 425 490 705 At Warrenville Road 2.0 265 370 430 65 SPRING BROOK NO. At mouth 7.0 495 685 795,40 SPRING BROOK NO. 2 At river mile 2.78 9.99 545 825 960,290 Approximately,660 feet upstream of 75 th Street 3.30 90 330 400 600 *Data not available 47

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR SPRING BROOK CREEK At Medinah Road 6.55 58 790 90,208 At Circle Avenue 4.97 408 64 704 926 At Foster Avenue 2.60 97 296 340 446 SPRING ROAD TRIBUTARY At mouth.25 320 440 48 565 Just upstream of State Route 83 0.82 265 365 395 465 ST. JOSEPH CREEK At mouth.80 730,60,365,900 At Main Street.0 70,25,320,830 At the Burlington Northern Railroad 0.40 690,090,290,770 Downstream of Maple Avenue 3.28 405 645 760,055 At Cumnor Road.65 290 460 540 750 At 63 rd Street 0.80 205 330 390 55 Downstream of 55 th Street 2.83 55 250 295 405 ST. JOSEPH CREEK TRIBUTARY At confluence 0.30 54 87 0 40 TRIBUTARY (A) At mouth 0.50 25 95 230 320 Above Warrenville Road 0.20 55 90 05 45 TRIBUTARY 2 (B) At the Burlington Northern Railroad 0.47 45 230 275 385 At Ogden Avenue 0.9 90 45 75 245 ST. PROCOPIUS CREEK Approximately 600 feet downstream of Mill Bridge Lane 0.68 70 265 320 440 *Data not available 48

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR SOUTH FORK OF WESTWOOD CREEK Just downstream of Army Trail Road 3.60 68 02 220 Just downstream of control structure 3.40 65 99 08 27 Just downstream of Fullerton Avenue 2.60 7 282 323 438 SUGAR CREEK At confluence with Salt Creek 4.0 650 890 966,43 At Villa Avenue 3.65 570 780 850,000 At State Route 83.58 400 542 596 700 SUGAR CREEK TRIBUTARY A At southern corporate limits for Village of Villa Park 0.3 205 265 290 335 UNNAMED CREEK SOUTH OF FOXCROFT ROAD At mouth 0.30 85 250 285 380 Approximately,000 feet downstream of 87 th Street 0.20 85 50 85 280 UNNAMED CREEK SOUTH OF 87 TH STREET At mouth.30 80 2 225 2 295 2 505 2 Approximately 80 feet downstream of Ring Road 0.60 25 2 25 2 70 2 320 2 UNNAMED STREAM NORTH OF 22 ND STREET IN At mouth 0.88 235 340 390 605 At Finley Road 0.49 75 254 29 45 UNNAMED TRIBUTARYTO KRESS CREEK At mouth at Kress Creek.00 95 35 55 95 Increased due to interbasin flow 2 Decreased due to interbasin flow *Data not available 49

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR WARDS CREEK At Interstate Highway 55 0.75 7 * 207 * WAUBANSEE CREEK At Kane-Kendall County boundary 6.50 770,220,447,950 WEST BRANCH DUPAGE RIVER Approximately 475 feet upstream of confluence with Unnamed Creek (south of 87 th Street) 24.5 3,545 4,970 5,655 7,575 At DuPage-Will County line 23.0 3,50 4,920 5,600 7,500 At Hillside Road 07.3 3,075 4,000 4,400 5,250 At Ogden Avenue 05.0 2,880 3,740 3,960 5,000 Upstream of Fawell Dam 00.0 2,900 4,00 4,600 5,850 At confluence with Kress Creek 80.3 2,460 3,460 3,850 4,900 Above mouth, Kress Creek 62.0,800 2,600 2,900 3,900 At Roosevelt Road (State Highway 38) 58.5,700 2,400 2,700 3,550 At North Avenue 28.5 970,360,540,980 Downstream limit of study (near Jefferson Street) in Village of Hanover Park 6.4 730,00,60,460 At Lake Street 0. 600 830 930,70 At Irving Park Road 4.70 335 460 505 640 WEST BRANCH SAWMILL CREEK At Interstate Highway 55 0.75 78 290 345 495 Near Cass School 0.58 49 245 290 420 Near Bay View 0.42 46 238 285 402 WEST BRANCH TRIBUTARY NO. Just upstream of Forest Preserve Road.4 65 40 90 305 *Data not available 50

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR WEST BRANCH TRIBUTARY NO. 2 (COUNTRY CREEK) At mouth 3.70 278 390 430 569 WEST BRANCH TRIBUTARY NO. 3 At mouth.32 90 335 430 650 WEST BRANCH TRIBUTARY NO. 4 At mouth 2.9 275 475 590 880 WEST BRANCH TRIBUTARY NO. 5 At mouth 0.07 35 * 95 * WEST BRANCH TRIBUTARY NO. 6 At mouth 0.8 55 240 285 675 WEST BRANCH TRIBUTARY NO. 7 At mouth 0.6 55 0 50 20 WEST BRANCH TRIBUTARY TO SPRING BROOK CREEK At Roselle Road.50 24 86 2 275 WESTWOOD CREEK At confluence with Salt Creek 5.62 37 550 648 860 Approximately 320 feet upstream of Lincoln Street 4.25 239 345 394 570 At Lake Street 4.22 236 343 389 520 Approximately 200 feet downstream of Country Club 0.66 49 66 74 87 *Data not available 5

TABLE 3 - SUMMARY OF DISCHARGES - continued FLOODING SOURCE DRAINAGE AREA PEAK DISCHARGES (cfs) AND LOCATION (sq. miles) 0-YEAR 50-YEAR 00-YEAR 500-YEAR WINDING CREEK At mouth.5 95 340 420 630 WINFIELD CREEK At Roosevelt Road at Schaffner Road 6.95 430 585 665 935 At Beverly Avenue 6.35 340 450 50 70 At Chicago and North Western Railroad 5.60 225 290 320 425 At low flow dam at mile 4.60 4.30 320 430 490 695 At Main Street 3.69 370 50 590 855 At downstream corporate limits for Village of Carol Stream 2.9 330 455 530 760 59 TH STREET DITCH At County Line Road 0.5 2 83 22 293 63 RD STREET DITCH At mouth 4.90 70,30,330,850 At County Line Road 3.70 565 900,070,490 At Madison Street 2.20 390 620 729,00 At Lake Hinsdale 0.60 85 295 349 490 79 TH STREET DITCH At County Line Road.00 9 4 65 226 At 79 th Street 0.90 77 8 40 90 At Hamilton Street 0.80 57 90 05 45 *Data not available 3.2 Hydraulic Analyses Analyses of the hydraulic characteristics of flooding from the source studied were carried out to provide estimates of the elevations of floods of the selected recurrence intervals. Users should be aware that flood elevations shown on the FIRM represent rounded whole-foot elevations and may not exactly reflect the elevations shown on the Flood Profiles or in the Floodway Data tables in the FIS report. For construction and/or floodplain management purposes, users are encouraged to use the flood elevation data presented in this FIS in conjunction with the data shown on the FIRM. 52

Precountywide Analyses Each jurisdiction within DuPage County has a previously printed FIS report. The hydraulic analyses described in these reports have been compiled and are summarized below. Locations of selected cross sections used in the hydraulic analyses are shown on the Flood Profiles (Exhibit ). For stream segments for which a floodway was computed (Section 4.2), selected cross section locations are also shown on the Flood Boundary Floodway Map (Exhibit 2). Cross-section data for the streams studied in detail were obtained by field measurement. All bridges and culverts were surveyed to obtain structural geometry and elevation data. The hydraulic analyses for this study were based on the effects of unobstructed flow. The flood elevations shown on the profiles are considered valid only if hydraulic structures remain unobstructed, other planned flood control structures operate properly, and do not fail. All elevations are referenced to National Geodetic Vertical Datum of 929 (NGVD) formerly referred to as mean sea level with the 929 General Adjustment; elevation reference marks used in the study are shown on the maps. Qualifying bench marks within a given jurisdiction that are cataloged by the National Geodetic Survey (NGS) and entered into the National Spatial Reference System (NSRS) as First or Second Order Vertical and have a vertical stability classification of A, B, or C are shown and labeled on the FIRM with their 6- character NSRS Permanent Identifier. Bench marks cataloged by the NGS and entered into the NSRS vary widely in vertical stability classification. NSRS vertical stability classifications are as follows: Stability A: Monuments of the most reliable nature, expected to hold position/elevation well (e.g., mounted in bedrock) Stability B: Monuments which generally hold their position/elevation well (e.g., concrete bridge abutment) Stability C: Monuments which may be affected by surface ground movements (e.g., concrete monument below frost line) Stability D: Mark of questionable or unknown vertical stability (e.g., concrete monument above frost line, or steel witness post) 53

In addition to NSRS bench marks, the FIRM may also show vertical control monuments established by a local jurisdiction; these monuments will be shown on the FIRM with the appropriate designations. Local monuments will only be placed on the FIRM if the community has requested that they be included, and if the monuments meet the aforementioned NSRS inclusion criteria. To obtain current elevation, description, and/or location information for bench marks shown on the FIRM for this jurisdiction, please contact the Information Services Branch of the NGS at (30) 73-3242, or visit their Web site at www.ngs.noaa.gov. It is important to note that temporary vertical monuments are often established during the preparation of a flood hazard analysis for the purpose of establishing local vertical control. Although these monuments are not shown on the FIRM, they may be found in the Technical Support Data Notebook associated with this FIS and FIRM. Interested individuals may contact FEMA to access this data. Roughness coefficients (Manning s n ) for the hydraulic computations were assigned on the basis of field inspection, analyses of field photographs (USACE, 973-979) and sound engineering judgment. Starting water-surface elevations for the streams studied in detail and limited detail were determined using corresponding flood elevations on the main stem, flood profiles from previous studies by the State of Illinois and the SCS (State of Illinois, 975; and Des Plaines River Watershed Steering Committee, January 976), normal depth computations, and rating curves. Backwater effects at confluences with larger stream systems are reflected on the flood profiles (Exhibit ). The water-surface elevations for the streams studied in detail and limited detail were computed using either the SCS WSP-2 backwater computer program or the USACE HEC-2 step-backwater computer program (U.S. Department of Agriculture, 974; USACE, HEC-2 Water-Surface Profiles, Computer Program723-X6-L202A, 973). The USACE HEC-2 model was used for all streams studied in detail and limited detail except for Meacham Creek, Sawmill Creek, Salt Creek, Spring Brook, and Westwood Creek, which were modeled utilizing the SCS WSP-2 program (U.S. Department of Agriculture, 974). Flood profiles were drawn showing computed water-surface elevations for floods of the selected recurrence intervals (Exhibit ). Streams studied in detail have flood profiles drawn for the 500-year, 00-year, 50-year, and 0-year storm events, with the exception of Upper Salt Creek, Klein Creek Tributary No., Klein Creek Tributary No. 2, Sawmill Creek, Sawmill Creek Tributary No., Wards Creek, West Branch Tributary No. 5, West Branch Tributary No. 7, East Branch Tributary No., and East Branch Tributary No. 2, which have only the 0-year and 00-year profiles. 54

Data for the flooding area along the eastern boundary of the Village of Glen Ellyn, near Route 53, designated as Zone AH, was taken from the Glen Ellyn FIS. Channel cross-section data for Addison Creek, Addison Creek Tributary No., Addison Creek Tributary No. 2, Addison Creek Tributary No. 3, Bensenville Ditch, North Unnamed Creek, and South Unnamed Creek were obtained from field surveys. All bridges and culverts were surveyed to obtain elevation data and structural geometry. Water surface profiles for present conditions on Addison Creek were determined for the 0-, 50-, and 00-year floods using the HEC-2 step-backwater computer program. Water-surface profiles for present conditions on the Addison Creek tributaries were determined for the 0-, 50-, 00-, and 500-year floods using the WSP-2 computer program (USACE, 984). Water-surface elevations for floods of the selected recurrence intervals on Bensenville Ditch, South Unnamed Creek, and North Unnamed Creek were computed using the HEC-2 step-backwater computer program(usace, 984). Starting water-surface elevations on the Addison Creek tributaries were determined using the slope/area method. Starting water-surface elevations for Bensenville Ditch, South Unnamed Creek, and North Unnamed Creek were determined by performing a routing at restrictive culverts that cause ponding at York Road and the Chicago and North Western railroad embankment. Roughness coefficients for Addison Creek, Addison Creek Tributary No., Addison Creek Tributary No. 2, Addison Creek Tributary No. 3, Bensenville Ditch, North Unnamed Creek, and South Unnamed Creek were assigned based on field inspection, photographs, and engineering judgment (USGS, 967, and Chow, Ven Te, 959). Cross-section data for the backwater analyses of Bronswood Cemetery Tributary, Ginger Creek, and Spring Road Tributary were obtained by field surveys during October 977. At this time, the ISWS crew conducting the field work also obtained elevation data and structural geometry for the bridges on each creek. Water-surface elevations on Bronswood Cemetery Tributary and Spring Road Tributary, for all designated recurrence intervals, were computed through use of the USACE HEC-2 step-backwater computer program (USACE, 976). Elevations for the approximate flooding areas were determined by field inspection. Flood profiles on Ginger Creek for the 0-, 50-, and 500-year floods were computed by the ISWS with the SCS WSP-2 step-backwater program (U.S. Department of Agriculture, 976), necessary input information was supplied by the SCS. The 00-year flood elevations and resulting floodplains, floodways, and profiles were computed by the ISWS and reported in a January 980 flood study of Salt Creek and its tributaries (Illinois Department of Transportation, 980). 55

Starting water-surface elevations for Bronswood Cemetery Tributary, Ginger Creek, and Spring Road Tributary were taken from the Salt Creek profiles for the corresponding recurrence intervals. Channel roughness factors (Manning s n ) used in the hydraulic computations of Bronswood Cemetery Tributary, Ginger Creek, and Spring Road Tributary were selected by engineering judgment and from field observations of the stream and floodplain areas. The factors were chosen to be consistent with commonly reported values (Dougherty, R. L, 977; Chow, V. T., 964; Chow, V. T., 959). Cross-section data for Crabtree Creek and Prentiss Creek were obtained from field surveys. Water-surface profiles for Crabtree Creek and Prentiss Creek were computed through use of the USACE s HEC-2 step-backwater computer program (USACE, HEC-2 Water-Surface Profiles, Computer Program 723-X6-L202A, 973). Profiles were determined for the 0-, 50-, 00-, and 500-year floods (Exhibit ). Starting elevations at the downstream corporate limits for Crabtree Creek and Prentiss Creek were determined from profiles of these streams computed for the FIS of the unincorporated areas of DuPage County (FEMA, 982). Roughness coefficients (Manning s n ) for Crabtree Creek and Prentiss Creek were estimated from field inspection at cross-section locations, and from model calibration based on high water marks. Both overbank and channel cross sections for Cress Creek, Winding Creek, Unnamed Creek South of Foxcroft Road, and Unnamed Creek South of 87 th Street were field surveyed. Water-surface elevations for Cress Creek, Winding Creek, Unnamed Creek South of Foxcroft Road, and Unnamed Creek South of 87 th Street were computed for the 0-, 50-, 00-, and 500-year floods using a HEC-2 computer step-backwater model (USACE, HEC-2 Water-Surface Profiles, Computer Program 723-X6- L202A, 973). The depth of shallow flooding along Bailey Road from Winding Creek in the City of Naperville was also computed using a HEC-2 model. The excess 00-year discharge which the underground storm sewer was incapable of handling was routed across surveyed ground-surface cross sections. Starting water-surface elevations for Cress Creek, Unnamed Creek South of Foxcroft Road, Winding Creek were calculated using the slope/area method. Roughness coefficients (Manning s n ) for Cress Creek were estimated by field inspection and by comparison of computed profiles with high-water marks. Cross-section data for Devon Avenue Tributary, and Meacham Creek, and bridges in the area were obtained from field surveys by the Illinois Division of Water 56

Resources supplemented with field surveys by a contractor for the SCS. In some cases, these cross sections were extended using topographic maps with a 2-foot contour interval (Floodplain Topographic Maps, 973). Water-surface profiles for Devon Avenue Tributary, and Meacham Creek were developed using the SCS WSP-2 Water-Surface Profile Computer Program (U.S. Department of Agriculture, 974). Profiles were determined for the 0-, 50-, 00-, and 500-year floods for all flooding sources. Starting elevations for Devon Avenue Tributary, and Meacham Creek were taken from previously published data (Des Plaines River Steering Committee, 975). Valley and channel roughness coefficients for Devon Avenue Tributary, and Meacham Creek were determined from field observations, USGS Water Supply Paper 849 (U.S. Department of the Interior, 967), and the SCS Guide for Selecting Roughness Coefficients (U.S. Department of Agriculture, 963). Cross-section data for East Branch DuPage River, North Branch St. Joseph Creek, South Branch St. Joseph Creek, and Lacey Creek were obtained by field measurement. The 00-year water-surface elevation on the East Branch DuPage River was computed through use of the USACE HEC-2 step-backwater computer program (USACE, HEC-2 Water-Surface Profiles, 976). Water-surface profiles for North Branch St. Joseph Creek, South Branch St. Joseph Creek, and Lacey Creek were developed using the USACE HEC-2 step-backwater computer model (USACE, HEC-2 Water-Surface Profiles, Computer Program 723-X6-L202A, 973). For North Branch and South Branch of St. Joseph Creek, starting elevations were determined from concurrent flowlines with the main stem. Roughness coefficients (Manning s n ) for East Branch Dupage River, North Branch St. Joseph Creek, South Branch St. Joseph Creek, and Lacey Creek were estimated by field inspection at the various cross sections. Stream cross sections and bridge sections for East Branch Sawmill Creek, Sawmill Creek, and West Branch Sawmill Creek were surveyed using land survey techniques. All of the cross sections on Sawmill Creek and the cross sections downstream from 75 th Street on East Branch Sawmill Creek were surveyed by the SCS; upstream sections were surveyed by Harza. All sections on West Branch Sawmill Creek were surveyed by Harza. Water-surface elevations for floods of the selected recurrence intervals were computed using hydraulic models for East Branch Sawmill Creek and Sawmill Creek prepared by the SCS (Des Plaines River Watershed Steering Committee, 976). Both models were extended by Harza to cover the entire stream within the City of Darien. The models were developed using the SCS WSP-2 57

step-backwater program (U.S. Department of Agriculture, 976). Mathematical relationships used in the model include the standard step-backwater procedure which estimates total energy at each cross section and accounts for friction losses between sections using Manning s formula. The model requires discharge, crosssection geometry, bridge geometry, starting water-surface elevation, and roughness data to simulate flood flow conditions. West Branch Sawmill Creek was modeled by Harza using the WSP-2 program. Starting water-surface elevations for East Branch Sawmill Creek, Sawmill Creek, and West Branch Sawmill Creek were determined from previous studies by the SCS (Des Plaines River Watershed Steering Committee, 976). Roughness coefficients for East Branch Sawmill Creek, Sawmill Creek, and West Branch Sawmill Creek were assigned on the basis of field inspection and previous analyses by the SCS. The cross-sectional data of the stream and floodplain, hydraulic structures such as bridges, culverts, dams, weirs, and other hydraulic controls for East Branch Tributary No. 2 were surveyed in 987 and 994 by Donohue and Associates. As they were surveyed, State Plane Coordinates were determined for each surveyed elevation location. Where possible, all of the surveyed cross-section points were used in the analysis. If any extra information was needed, such as horizontal extensions, the County s XDI software and digital topography were used as needed. In addition to the surveyed cross-sections, there were also fabricated cross sections used in the analysis. The fabricated cross sections were created for various reasons. Some of the surveyed cross sections were surveyed with no state plane coordinates. For this situation, the approximate location is determined and the State Plane Coordinates were assumed. This data was then used along with the surveyed elevations. There were also fabricated sections generated from existing surveyed sections. Hydraulic analysis for East Branch Tributary No. 2 was conducted using the continuous simulation hydraulic analysis software FEQ. Using FEQ, a detailed model of the Tributary 2 drainage network was developed. The model simulates flow storage in detention ponds, natural storage areas and floodplains. It also calculates the depth and discharge of flow through open channels, storm sewers, and overflow paths. Cross-section data for Flagg Creek were obtained from field measurements by Harza personnel. All hydraulic information for Flagg Creek was obtained from the Cook County FIS (FEMA, 2000). Water-surface elevations for floods of selected recurrence intervals were computed using a hydraulic model for Flagg Creek prepared by Harza. The model was developed using the WSP-2 backwater program of the U.S. 58

Department of Agriculture, Soil Conservation Service (SCS) (U.S. Department of Agriculture, 976). Mathematical relationships used in the model include the standard step-backwater procedure which estimates total energy at each cross section and accounts for friction losses between sections using Manning s formula. The model requires discharge, cross-section geometry, bridge geometry, starting water-surface elevations, and roughness data to simulate flood conditions. Profiles of water-surface elevations were computed for floods of the selected recurrence intervals (Exhibit ). On the profile for Flagg Creek, the 50- and 00- year flood profiles converge at station 5490 and are shown coincident to the upstream limit of detail study. The starting water-surface elevation for Flagg Creek was the 0-year flood elevation for the Des Plaines River (Des Plaines River Steering Committee, 975). Roughness coefficients for Flagg Creek were assigned on the basis of field inspection. Cross-section data for Klein Creek, Klein Creek Tributary No. 2, and Klein Creek Tributary No. 3 were obtained by field measurement. Water-surface elevations of floods of the selected recurrence intervals were computed using the USACE HEC-2 step-backwater computer program (USACE, HEC-2 Water-Surface Profiles, Computer Program 723-X6-L202A, 973) for Klein Creek, Klein Creek Tributary No. 2, and Klein Creek Tributary No. 3. Flood profiles were drawn showing computed water-surface elevations to an accuracy of 0.5 foot for floods of the selected recurrence intervals. Starting water-surface elevations for Klein Creek, Klein Creek Tributary No. 2, and Klein Creek Tributary No. 3 were calculated using the slope/area method. Roughness coefficients for the hydraulic computations of Klein Creek, Klein Creek Tributary No. 2, and Klein Creek Tributary No. 3 were assigned on the basis of field inspection of floodplain areas. Cross-section data for part of Kress Creek and for the entire Unnamed Tributary of Kress Creek were obtained by field measurement. Cross sections for Kress Creek up to Hawthorne Lane are identical to those used for a previous USACE Flood Plain Information Report (USACE, 975). In addition, channel modifications to Kress Creek for a distance of 600 feet upstream of the Elgin, Joliet, and Eastern Railroad, and culverts at the railroad crossing were inspected in March 978 and incorporated into the hydraulic model. Water-surface profiles for Kress Creek, and Unnamed Tributary to Kress Creek were developed through use of the USACE HEC-2 step-backwater computer program (USACE, HEC-2 Water-Surface Profiles, Computer Program 723-X6- L202A, 973). 59

Starting water-surface elevations for Kress Creek and Unnamed Tributary to Kress Creek were calculated using the slope/area method. Roughness coefficients for the hydraulic computations of Kress Creek and Unnamed Tributary to Kress Creek were assigned on the basis of field inspection of floodplain areas. Cross sections for the backwater analyses of Norton Creek and Norton Creek Tributary were determined from field surveys with some overbank cross sections being determined from topographic maps at a scale of :4,800, with a contour interval of four feet (U.S. Department of the Interior, 972). Cross-section locations were at close intervals above and below bridges, dams, and culverts in order to compute the significant backwater effects of these structures. Water-surface elevations of floods of the selected recurrence intervals on Norton Creek and Norton Creek Tributary were computed through use of the USACE HEC-2 step-backwater computer program (U.S. Army Corps of Engineers, February 972). This program relates stream geometry, characteristics, and discharge to stream elevation. The starting downstream water-surface elevations for Norton Creek and Norton Creek Tributary used in the HEC-2 step-backwater program were computed by the normal depth methods (USACE, February 972). Roughness coefficients for Norton Creek and Norton Creek Tributary were determined by field inspection and engineering judgment. Cross sections for the backwater analyses on Salt Creek and Westwood Creek were field surveyed by the SCS. Cross-section data for Salt Creek were obtained from Regulation of Construction Within the Floodplain of Lower Salt Creek and Tributaries (Illinois Department of Transportation, 980). Additional cross sections on the upper portion of Westwood Creek not included in the SCS studies were surveyed by Harza. Sections were located at close intervals above and below bridges and culverts in order to compute the significant backwater effects of these structures. Water-surface elevations of floods for selected recurrence intervals were computed using hydraulic models for Westwood Creek prepared by the SCS. The models were developed using the SCS WSP-2 backwater program (U.S. Department of the Interior, 963). The models involve a standard step-backwater computation procedure which estimates total energy at each stream cross section and accounts for friction losses between sections using Manning s formula. The model requires discharge, stream channel and floodplain geometry, starting watersurface elevation, and roughness data to simulate flood flow conditions. 60

Starting water-surface elevations for Salt Creek were developed by the slope/area method. Starting elevations for Westwood Creek were determined from the Salt Creek hydraulic model. Channel roughness factors for Salt Creek and Westwood Creek were assigned on the basis of field inspection of floodplain areas and from previous studies by the SCS. Cross-section data for the backwater analyses of Spring Brook Creek and the West Branch Tributary to Spring Brook Creek were obtained by field surveys during April-May 979. At that time, the ISWS crew conducting the field work also obtained elevation data and structural geometry for the bridges on each creek. Elevation data for portions of Spring Brook Creek were also provided by the SCS. Flood profiles on Spring Brook Creek and the West Branch Tributary to Spring Brook Creek for the 0-, 50-, 00-, and 500-year floods were computed by the ISWS with the SCS WSP-2 step-backwater program (Wight Consulting Engineers, Inc., 978); the necessary input information was supplied by SCS and the field surveys by ISWS. Starting water-surface elevations on Spring Brook Creek for all designated recurrence intervals were determined from downstream profiles of Spring Brook Creek. Starting water-surface elevations for the West Branch Tributary Spring Brook Creek were taken from profiles of the mainstem Spring Brook Creek. Channel roughness factors (Manning s n ) used in the hydraulic computations, for Spring Brook Creek and West Branch Tributary Spring Brook Creek were selected on the basis of field inspection of floodplain areas. The factors were chosen to be consistent with commonly reported values (U.S. Department of Agriculture, 965; Chow, V. T., 964; Chow, V. T., 959). Cross sections for St. Joseph Creek, Rott Creek, St. Procopius Creek, Tributary (A), Tributary 2 (B), East Branch Tributary No. 3, and East Branch Tributary 4 were field surveyed. For St. Joseph Creek, the below water sections were obtained by field measurement and the overbank sections were obtained from aerial photographs (Northeastern Illinois Planning Commission, 975). In all cases, cross sections were located at close intervals above and below bridges and culverts in order to compute the significant backwater effects of these structures. Water-surface elevations of floods of the selected recurrence intervals were computed for St. Joseph Creek, Rott Creek, St. Procopius Creek, Tributary (A), Tributary 2 (B), East Branch Tributary No. 3, and East Branch Tributary No. 4 through use of the USACE HEC-2 step-backwater computer model (USACE, HEC-2 Water-Surface Profiles, Computer Program 723-X6-L202A, 973). Starting water-surface elevations for St. Joseph Creek were calculated using the slope/area method. 6

Roughness coefficients for St. Joseph Creek, Rott Creek, St. Procopius Creek, Tributary (A), Tributary 2 (B), East Branch Tributary No. 3, and East Branch Tributary No. 4 were estimated by field inspection of the streams and floodplains. Cross-section data for St. Joseph Creek Tributary were obtained from field measurements. Hydraulic analyses for the St. Joseph Creek Tributary were made using the backwater program WSP-2 of the U.S. Department of Agriculture, Soil Conservation Service (SCS) (U.S. Department of Agriculture, 976). Mathematical relationships used in the model include the standard step method for backwater computations which estimates total energy at each cross section and accounts for friction losses between sections using Manning s formula. The model requires discharge, cross-section geometry, bridge geometry, starting water-surface elevations, and roughness data to simulate flood flow conditions. The starting water-surface elevations for St. Joseph Creek Tributary are the watersurface elevations on St. Joseph Creek at the confluence of the two streams. Cross sections for Sugar Creek were obtained from topographic maps (USDA, SCS, 975). Water-surface elevations for Sugar Creek were computed using the USACE HEC- 2 step-backwater computer program (USACE, 99). Flood profiles were drawn showing computed water-surface elevations for floods of the selected recurrence intervals. Starting water-surface elevations for Sugar Creek were taken from the Salt Creek profiles for the corresponding recurrence intervals. Roughness factors (Manning s n ) used in the hydraulic computations for Sugar Creek were chosen by engineering judgment and were based on field inspections of the streams and floodplain areas. The factors were chosen to be consistent with commonly reported values (Chow, V. T., 964; Chow, V. T., 959). Cross-section data for the backwater analysis of Sugar Creek Tributary A were obtained by field surveys during September 977. At this time, the Illinois State Water Survey crew conducting the field work also obtained elevation data and structural geometry for all bridges on the creek. Water-surface elevations on Sugar Creek Tributary A for all designated recurrence intervals were computed through use of the USACE HEC-2 stepbackwater computer program (USACE, November 976). Channel roughness factor (Manning s n ) used in the hydraulic computations of Sugar Creek Tributary A was selected by engineering judgment and from field observations of the stream and floodplain areas. The factor was chosen to be 62

consistent with commonly reported values (Dougherty, R. L, 977; Chow, V. T., 964; Chow, V. T., 959). Cross sections for Waubansee Creek were resurveyed to reflect development within the floodplain that had occurred subsequent to the previous FIS. The 00-year water-surface elevation for the restudy of Waubansee Creek was calculated using the USACE HEC-2 step-backwater program (U.S. Department of Agriculture, 965). Starting water-surface elevations for Waubansee Creek were calculated using the slope/area method. Cross sections used for the West Branch DuPage River are identical to those used in a previous Floodplain Information Report (USACE, 975). Channel portions of these cross sections were field surveyed, while overbank portions were determined photogrammetrically. Water-surface profiles for West Branch DuPage River were developed through use of the USACE HEC-2 step-backwater computer program (USACE, HEC-2 Water-Surface Profiles, Computer Program 723-X6-L202A, 973). Starting elevations for the West Branch DuPage River were derived from the Flood Plain Information Report (USACE, 975). Stream mileages for the West Branch DuPage River and Kress Creek were obtained from the Hydrologic Investigations Atlases (U.S. Department of the Interior, 965). Starting watersurface elevations for the tributaries were determined from the West Branch hydraulic model (U.S. Department of Agriculture, 973). Starting water-surface elevations for the West Branch DuPage River model in Schaumburg were obtained from downstream flood profiles prepared by the USACE for the Hanover Park FIS (U.S. Department of Housing and Urban Development, unpublished). Starting elevations were determined from the Poplar Creek hydraulic model. Roughness coefficients (Manning s n ) for West Branch DuPage River were estimated by field inspection and by comparison of computed profiles with highwater marks. Cross-section data for Winfield Creek were obtained from field surveys. Water-surface profiles for Winfield Creek were computed through use of the USACE HEC-2 step-backwater computer program (USACE, HEC-2 Water- Surface Profiles, Computer Program 723-X6-L202A, 973). Profiles were determined for the 0-, 50-, 00-, and 500-year floods (Exhibit ). For Winfield Creek between the Chicago and North Western Railroad and Main Street, two sets of profiles were computed using different sets of assumptions: () maximum inflow at Main Street and corresponding starting water-surface elevations at the 63

railroad, and (2) maximum pond elevations behind the railroad bridge and corresponding discharges through the reach. The profiles for the second case were used since they were higher for the entire reach. Starting water-surface elevations for Winfield Creek were calculated using the slope/area method. Roughness coefficients (Manning s n ) for Winfield Creek were estimated by field inspection. Cross-section data for the Unnamed Stream North of 22 nd Street were obtained by field measurement. Water-surface profiles for Unnamed Tributary North of 22 nd Street were developed using a HEC-2 computer step-backwater model (USACE, HEC-2 Water-Surface Profiles, Computer Program 723-X6-L202A, 973). Profiles were determined for the 0-, 50-, 00-, and 500-year floods (Exhibit ). Flood elevations for the Unnamed Tributary of 22 nd Street may be raised by debris blockage of bridges or culverts. Starting water-surface elevations Unnamed Tributary North of 22 nd Street were calculated using the slope/area method. Roughness coefficients for Unnamed Tributary North of 22 nd estimated by field inspection at the various cross section locations. Street were Channel and overbank cross sections for the 59 th Street Ditch were determined by land surveying. Water-surface elevations for floods of selected recurrence intervals for 59 th Street Ditch were computed using the WSP-2 and HEC-2 backwater programs (U.S. Department of Agriculture, 976; USACE, November 976). Mathematical relationships used in the models include the standard step-backwater procedure which estimates total energy at each cross section and accounts for friction losses between sections using Manning s formula. The model requires discharge, crosssection geometry, bridge geometry, starting water-surface elevation, and roughness data to simulate flood flow conditions. The hydraulic model for the 59 th Street Ditch was prepared by Harza. The starting water-surface elevations for the 59 th Street Ditch were estimated using the slope/area method at the Hinsdale boundary with Burr Ridge. Roughness coefficients (Manning s n values) for 59 th Street Ditch were assigned on the basis of field inspection and previous analysis by the SCS. Cross-section data for the 63 rd Street Ditch were obtained from the SCS Floodplain Information Maps and Profiles (Des Plaines River Steering 64

Committee, 975) and were supplemented with data from the Improvement Plan for Burr Ridge Meadows (Baranecki, Vigilio, and Associates, 977). Hydraulic analyses for the 63 rd Street Ditch and East Branch Sawmill Creek were made using the SCS backwater program WSP-2 (U.S. Department of Agriculture, 974). Mathematical relationships used in the model include the standard stepbackwater procedure which estimates total energy at each cross section and accounts for friction losses between sections using Manning s formula. The model requires discharge, cross-section geometry, bridge geometry, starting water-surface elevations, and roughness data to simulate flood flow conditions. The SCS previously had developed backwater simulation models for much of 63 rd Street Ditch and for East Branch Sawmill Creek (Des Plaines River Watershed Steering Committee, 975). Harza extended the model for 63 rd Street Ditch to include the reach upstream from Madison Street. Lake Hinsdale elevations were determined from a continuation of the analyses from 63 rd Street Ditch. Starting water-surface elevations for 63 rd Street Ditch were calculated by operation of the WSP-2 model of Flagg Creek developed by the SCS and used by the Des Plaines River Steering Committee (Des Plaines River Watershed Steering Committee, 975). Roughness coefficients (Manning s n values) for 63 rd assigned on the basis of field inspection. Street Ditch were Land surveys provided cross-section data for 79 th Street Ditch, Plainfield Road Ditch. Water-surface elevations for 79 th Street Ditch and Plainfield Road Ditch, floods of the selected recurrence intervals were computed using the SCS WSP-2 stepbackwater computer program (U.S. Department of Agriculture, 976). The starting water-surface elevation for Plainfield Road Ditch was obtained from the Indian Head Park FIS (U.S. Department of Housing and Urban Development, November, 2000). Roughness coefficients (Manning s n values) for 79 th assigned on the basis of field inspection. Street Ditch were All bridges and culverts were surveyed to obtain elevation data and structural geometry. Table 4, Manning s n Values, shows the channel and overbank n values for the streams studied by detailed methods. 65

TABLE 4 - MANNING'S "n" VALUES Stream Channel "n" Overbank "n" Addison Creek 0.030-0.075 0.030-0.095 Addison Creek Tributary No. 0.030-0.075 0.030-0.095 Addison Creek Tributary No. 2 0.030-0.075 0.030-0.095 Addison Creek Tributary No. 3 0.030-0.075 0.030-0.095 Armitage Fork Bensenville Ditch 0.030-0.075 0.030-0.095 Brewster Creek 0.035 0.060-0.070 Briarwood Ditch Bronswood Cemetery Tributary 0.05-0.080 0.040-0.200 Crabtree Creek 0.035 0.065 Cress Creek 0.030 0.800 Des Plaines River 0.030 0.060 Devon Avenue Tributary 0.045-0.065 0.065-0.085 East Branch DuPage River 0.035-0.055 0.055-0.090 East Branch DuPage River Tributary No. 0.045-0.070 0.045-0.080 East Branch DuPage River Tributary No. 2 0.035-0.065 0.035-0.085 East Branch DuPage River Tributary No. 3 0.035-0.040 0.060-0.080 East Branch DuPage River Tributary No. 4 0.065-0.085 0.055-0.070 East Branch DuPage River Tributary No. 5 0.035-0.040 0.060-0.080 East Branch DuPage River Tributary No. 6 0.035-0.040 0.060-0.080 East Branch DuPage River Tributary No. 7 0.055-0.080 0.080-0.00 East Branch Sawmill Creek 0.035-0.075 0.040-0.095 Ferry Creek 0.05-0.040 0.045-0.080 Ferry Creek Tributary 0.055-0.065 0.065-0.085 Flagg Creek 0.035-0.070 0.060-0.085 Ginger Creek 0.03-0.040 0.040-0.060 Heritage Oaks Tributary Klein Creek 0.030-0.045 0.060-0.080 Klein Creek Tributary No. 2 0.035 0.065 Klein Creek Tributary No. 3 0.055 0.070 Kress Creek 0.05-0.080 0.040-0.00 Lacey Creek 0.040-0.060 0.040-0.080 Lombard Tributary Meacham Creek 0.045-0.065 0.065-0.085 Midwest Club Tributary North Branch St. Joseph Creek 0.035 0.070 North Unnamed Creek 0.030-0.075 0.030-0.095 Norton Creek 0.045-0.50 0.050-0.50 Norton Creek Tributary 0.030-0.055 0.045-0.055 Plainfield Road Ditch 0.035-0.050 0.030-0.090 Prentiss Creek 0.035-0.040 0.060-0.070 Rott Creek 0.035-0.040 0.060-0.080 Salt Creek 0.020-0.070 0.020-0.300 66

TABLE 4 - MANNING'S "n" VALUES - continued Stream Channel "n" Overbank "n" Sawmill Creek 0.055-0.065 0.065-0.090 Sawmill Creek Tributary No. 0.035-0.080 0.070-0.090 Sawmill Creek Tributary No. 3 0.040-0.00 0.050-0.20 South Branch St. Joseph Creek 0.035 0.060 South Fork of Westwood Creek 0.035-0.075 0.035-0.075 South Unnamed Creek 0.030-0.075 0.030-0.095 Spring Brook No. 0.035-0.055 0.070-0.00 Spring Brook No. 2 0.035 0.035 Spring Brook Creek 0.035-0.070 0.035-0.00 Spring Road Tributary 0.025-0.050 0.075 St. Joseph Creek 0.028-0.038 0.035-0.050 St. Joseph Creek Tributary 0.028-0.038 0.035-0.050 St. Procopius Creek 0.035-0.040 0.060-0.080 Sugar Creek 0.05-0.042 0.055-0.065 Sugar Creek Tributary A 0.020-0.042 0.060 Tributary (A) 0.035-0.040 0.060-0.080 Tributary 2 (B) 0.035-0.040 0.060-0.080 Unnamed Creek South of Foxcroft Road 0.300 0.050 Unnamed Stream North of 22 nd Street 0.045-0.080 0.050-0.070 Unnamed Tributary of Kress Creek 0.05-0.065 0.035-0.070 Waubansee Creek 0.035-0.055 0.050-0.070 West Branch DuPage River 0.035-0.050 0.040-0.00 West Branch Sawmill Creek 0.040-0.060 0.035-0.045 West Branch Tributary No. 0.050-0.080 0.095 West Branch Tributary No. 2 0.05-0.035 0.035-0.20 West Branch Tributary No. 3 0.040-0.070 0.085 West Branch Tributary No. 4 0.065 0.085-0.00 West Branch Tributary No. 5 0.050-0.070 0.065-0.085 West Branch Tributary No. 6 0.070 0.00 West Branch Tributary No. 7 0.050-0.060 0.065-0.00 West Branch Tributary to Spring Brook Creek 0.040-0.050 0.040-0.20 Westwood Creek 0.045-0.055 0.070-0.075 Winfield Creek 0.05-0.055 0.045-0.00 59th Street Ditch 0.030-0.035 0.035-0.065 63rd Street Ditch 0.07-0.040 0.025-0.060 79th Street Ditch 0.048-0.055 0.025-0.085 Several approximate study areas in the Village of Bloomingdale are a result of determined ponding from historical flooding. Flooding along the Bloomingdale Grove Tributary is caused from backwater from the West Branch Tributary to Spring Brook Creek. 67

The approximate flood elevations in the City of Darien were determined by field inspection and historic data. The 00-year flood elevation on the streams studied by approximate methods in the Villages of Downer s Grove, Carol Stream, and Woodridge was determined by solving Manning s equation for depth of flow in the channels (Woodward, Sherman M., 94). These streams were inspected in the field to obtain typical stream cross sections, average streambed slope, Manning s n values, and measurements at bridges and culverts. In the Village of Woodridge, these streams were inspected in the field to obtain typical stream cross sections, and measurements at bridges and culverts. Elevations for the approximate flooding areas in the Village of Oakbrook were determined by field inspection. For areas studied by approximate methods in the Village of Schaumburg, the extent of 00-year flooding was delineated using the USGS Hydrologic Atlas for the Palatine area and the FIA Flood Hazard Boundary Maps (U.S. Department of the Interior, 964; U.S. Department of Housing and Urban Development, 975). 3.3 Vertical Datum All FISs and FIRMs are referenced to a specific vertical datum. The vertical datum provides a starting point against which flood, ground, and structure elevations can be referenced and compared. Until recently, the standard vertical datum in use for newly created or revised FISs and FIRMs was the National Geodetic Vertical Datum of 929 (NGVD 29). With the finalization of the North American Vertical Datum of 988 (NAVD 88), many FIS reports and FIRMs are being prepared using NAVD 88 as the referenced vertical datum. All flood elevations shown in this FIS report and on the FIRM are referenced to NGVD 29. Structure and ground elevations in the community must, therefore, be referenced to NGVD 29. It is important to note that adjacent communities may be referenced to NAVD 88. This may result in differences in base flood elevations across the corporate limits between the communities. For more information on NAVD 88, see Converting the National Flood Insurance Program to the North American Vertical Datum of 988, FEMA Publication FIA- 20/June 992, or contact the Vertical Network Branch, National Geodetic Survey, Coast and Geodetic Survey, National Oceanic and Atmospheric Administration, Rockville, Maryland 2090 (Internet address http://www.ngs.noaa.gov). 4.0 FLOODPLAIN MANAGEMENT APPLICATIONS The NFIP encourages State and local governments to adopt sound floodplain management programs. To assist in this endeavor, each FIS provides 00-year floodplain data, which 68

may include a combination of the following: 0-, 50-, 00-, and 500-year flood elevations; delineations of the 00-year and 500-year floodplains; and 00-year floodway. This information is presented on the FIRM and in many components of the FIS, including Flood Profiles, Floodway Data tables, and Summary of Stillwater Elevation tables. Users should reference the data presented in the FIS as well as additional information that may be available at the local community map repository before making flood elevation and/or floodplain boundary determinations. 4. Floodplain Boundaries To provide a national standard without regional discrimination, the -percent annual chance (00-year) flood has been adopted by FEMA as the base flood for floodplain management purposes. The 0.2-percent annual chance (500-year) flood is employed to indicate additional areas of flood risk in the community. For the stream studied in detail, the 00- and 500-year floodplains have been delineated using the flood elevations determined at each cross section. Between cross sections, the boundaries were interpolated using topographic maps at a scale of :4,800, with contour intervals of 2 to 0 feet (State of Illinois, 976; USGS, 972, et cetera; State of Illinois, Floodplain Topographic Map for Salt Creek Watershed, 975). Approximate Methods Starting water-surface elevations for Klein Creek Tributary No. 3 studied by limited detail methods in the Village of Carol Stream were calculated using the slope/area method. Flood boundaries for several unnamed tributaries to the West Branch DuPage River were determined using approximate analyses. Depths of flooding along these streams were computed using the slope/area method. A small portion of Spring Brook southwest of the City of Naperville between 87 th and 95 th Streets was also studied by approximate analysis. Depth of the 00-year flood at this location was calculated from a stage-frequency curve prepared for a USGS crest stage gage at 83 rd Street. Part of the flood boundary just north of cross section E, for the Unnamed Creek South of Foxcroft Road, was delineated approximately using the contour map and the known water-surface elevation at the limit of detailed study. Also delineated by approximate methods were the limits of several detention ponds in the City of Naperville. Although many of these areas are residential lawns, they are designed to detain water during periods of heavy rainfall. Delineation of these areas was performed using information obtained from the city engineer s office and from Lindley and Sons, Inc. Flood boundaries for Zone AH near the Glen Ellyn eastern boundary were extrapolated from the boundaries shown in the Village of Glen Ellyn FIS using topographic maps (USGS, 972, et cetera). 69

Flood boundaries for areas studied by approximate methods were delineated using USGS Flood Prone Area Maps, and Regulatory Flood Plain Maps (USGS, 972, et cetera; USACE, 975). The 00- and 500-year floodplain boundaries are shown on the FIRM (Exhibit 2). On this map, the 00-year floodplain boundary corresponds to the boundary of the areas of special flood hazards (Zones A, AH, and AE), and the 500-year floodplain boundary corresponds to the boundary of areas of moderate flood hazards. In cases where the 00- and 500-year floodplain boundaries are close together, only the 00-year floodplain boundary has been shown. Small areas within the floodplain boundaries may lie above the flood elevations but cannot be shown due to limitations of the map scale and/or lack of detailed topographic data. 4.2 Floodways Encroachment on floodplains, such as structures and fill, reduces flood-carrying capacity, increases flood heights and velocities, and increases flood hazards in areas beyond the encroachment itself. One aspect of floodplain management involves balancing the economic gain from floodplain development against the resulting increase in flood hazard. For purposes of the NFIP, a floodway is used as a tool to assist local communities in this aspect of floodplain management. Under this concept, the area of the 00-year floodplain is divided into a floodway and a floodway fringe. The floodway is the channel of a stream, plus any adjacent floodplain areas, that must be kept free of encroachment so that the 00-year flood can be carried without substantial increases in flood heights. Minimum Federal standards limit such increases to.0 foot, provided that hazardous velocities are not produced. The floodway in this FIS is presented to local agencies as a minimum standard that can be adopted directly or that can be used as a basis for additional floodway studies. In Illinois though, under Revised Statutes, Section 65f, Chapter 9 as amended in 973 (Illinois Department of Transportation, 973), encroachment in the floodplain is limited to that which will cause only an insignificant increase in flood heights. Thus, at the recommendation of the Illinois Division of Water Resources, a floodway having no more than a 0.-foot surcharge has been delineated for this study. The floodways for East Branch Sawmill Creek and 63 rd Street Ditch were determined from the HUD-5 computer program (U.S. Department of Agriculture, 977). Floodways were computed without consideration of backwater from the receiving streams. Portions of the floodway for 63 rd Street Ditch lies outside of the corporate limits for the Village of Willowbrook. Conveyance floodways were determined for each modeled open channel cross section for East Branch Tributary No. 2 using the FEQUTL command using the PVSTATS computer program. The equal conveyance option was employed in the command. This command calculates cross-section 70

encroachments that result in equal losses of conveyance from each side of the floodplain. Encroachments are increased until either the water-surface elevation rises 0. foot or the total conveyance loss reaches 0 percent. Flagg Creek, St. Joseph Creek, and 59 th Street Ditch were determined using the HUD-5 computer program. An Act in Relation to the Regulations of the Rivers, Lakes, and Streams of the State of Illinois, approved June 0, 9, as amended (Illinois Revised Statutes, Chapter 9, 52 et. seq.), authorizes the IDOT to define floodplains and establish a permit procedure for regulating construction within such defined floodplains (Illinois Department of Transportation, 980). The floodway for Ginger Creek was taken directly from the IDOT study. Floodway widths for Salt Creek were computed at cross sections. Between cross sections, the floodway boundaries were interpolated. For Salt Creek, because the mapped floodway extends outside the mapped 00-year floodplain, the floodway was delineated within the 00-year floodplain using engineering judgment. The floodway for Salt Creek extends beyond the corporate limits for City of Elmhurst. The floodways for Spring Road Tributary were taken directly from the Illinois Department of Transportation study of Salt Creek (Illinois Department of Transportation, 980). The floodway for Sugar Creek Tributary A was determined using the HUD-5 computer program (U.S. Department of Agriculture, 977). A portion of the floodway for Salt Creek lies outside the corporate limits of Village of Villa Park. Floodways for streams tributary to the West Branch DuPage River were computed without consideration of backwater flooding from the West Branch. Near the mouth of a few of these streams, therefore, floodway surcharge elevations are below rather than above the 00-year elevations determined by the West Branch backwater and indicated on the flood profiles. The floodway along the unnamed tributary north of 22 nd Street was computed without consideration of backwater flooding near its mouth. Floodway surcharge elevations along the lower portion of the unnamed stream, therefore, are below rather than above the 00-year flood elevations as determined by backwater flooding. No floodway was delineated on Rott Creek above the East-West Tollway, as the recent channel improvements in this area contain the 00-year flood. A floodway is not generally appropriate in areas such as that along Bailey Road, where overland flow occurs because existing storm sewers are incapable of conveying flood discharges. For this reason, no floodway was computed along Winding Creek. 7

For all other streams, the floodways were computed on the basis of equal conveyance reduction from each side of the floodplain. The results of these computations are tabulated at selected cross sections for each stream segment for which a floodway is computed (Table 5). The computed floodways are shown on the revised FIRM or FBFM (Exhibit 2). In cases where the floodway and the 00- year floodplain boundaries are either close together or collinear, only the floodway boundary is shown. The area between the floodway and 00-year floodplain boundaries is termed the floodway fringe. The floodway fringe encompasses the portion of the floodplain that could be completely obstructed without increasing the water-surface elevation of the 00-year flood by more than.0 foot at any point. Typical relationships between the floodway and the floodway fringe and their significance to floodplain development are shown in Figure, Floodway Schematic. SCHEMATIC Figure 72

FLOODING SOURCE CROSS SECTION Addison Creek (DPAC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPAC000 6,93 280,46 0.7 657.8 657.8 657.8 0.0 DPAC0002 6,834 305,367 0.7 657.8 657.8 657.8 0.0 DPAC0003 62,384 500 2,70 0.0 657.8 657.8 657.8 0.0 DPAC0004 62,774 523 2,453 0.0 657.8 657.8 657.8 0.0 DPAC0005 63,86 72 432 0.2 657.9 657.9 657.9 0.0 DPAC0006 64,48 7 397 0.2 657.9 657.9 657.9 0.0 DPAC0007 65,006 75,068 0. 657.9 657.9 657.9 0.0 DPAC0008 65,99 254 857 0. 657.9 657.9 657.9 0.0 DPAC0009 66,7 355,325 0. 657.9 657.9 657.9 0.0 In feet above confluence with Des Plaines River TABLE 5 DUPAGE COUNTY DATA ADDISON CREEK (DPAC)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE Addison Creek Tributary No. (DPAC) DPAC000 7,096 2 2 27 0.4 656.5 656.5 656.6 0. In feet above confluence with Des Plaines River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA ADDISON CREEK TRIBUTARY NO. (DPAC)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE Addison Creek Tributary No. 2 (DPAC) DPAC00 69,44 2 38 2.9 662.6 662.6 662.7 0. DPAC002 70,242 65 5 0.0 662.8 662.8 662.9 0. DPAC003 73,465 54 47.5 672.3 672.3 672.4 0. In feet above confluence with Des Plaines River TABLE 5 DUPAGE COUNTY DATA ADDISON CREEK TRIBUTARY NO. 2 (DPAC)

FLOODING SOURCE CROSS SECTION Addison Creek Tributary No. 3 (DPAC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPAC004 70,49 60 82 0.5 662.6 2 662.5 662.6 0. DPAC005 70,640 50 93 0.4 663. 663. 663.2 0. DPAC006 73,887 6 8 3.5 676. 676. 676.2 0. DPAC007 75,994 249,265 0.0 682.5 682.5 682.5 0.0 In feet above confluence with Des Plaines River 2 Elevation computed without consideration of backwater effects from Addison Creek Tributary No. 2 TABLE 5 DUPAGE COUNTY DATA ADDISON CREEK TRIBUTARY NO. 3 (DPAC)

FLOODING SOURCE CROSS SECTION Bensenville Ditch (DPBD) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPBD000 44,858 228 757 0.5 66.8 66.8 66.8 0.0 DPBD0002 45,49 673,78 0.5 66.9 66.9 66.9 0.0 DPBD0003 46,268 4 74 8.2 66.9 66.9 662.2 0.3 DPBD0004 46,448 5 98 3. 667.6 667.6 667.8 0.2 2 DPBD0005 46,669 786 2,852 0.2 667.8 667.8 668.0 0.2 DPBD0006 47,78 485,836 0.3 667.8 667.8 668.0 0.2 DPBD0007 48,048 504 2,360 0.2 667.9 667.9 668. 0.2 2 DPBD0008 48,735 48 2,298 0.2 667.9 667.9 668. 0.2 DPBD0009 49,609 2 284 442.3 667.9 667.9 668. 0.2 DPBD000 50,38 63 85 2.8 668. 668. 668.3 0.2 In feet above confluence with Des Plaines River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA BENSENVILLE DITCH (DPBD)

FLOODING SOURCE CROSS SECTION Des Plaines River (DPDP) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPDP000 33,73,54 8,58.0 594. 594. 594.2 0. DPDP0002 36,340,020 7,53.2 594.2 594.2 594.3 0. DPDP0003 38,993,256 7,388.2 594.3 594.3 594.4 0. DPDP0004 4,634 705 4,78.8 594.5 594.5 594.6 0. DPDP0005 44,255 696 5,468.5 594.6 594.6 594.7 0. DPDP0006 46,93 388 3,268 2.6 594.8 594.8 594.9 0. DPDP0007 49,500,252 7,2.2 595.2 595.2 595.3 0. DPDP0008 5,78,02 6,524.3 595.3 595.3 595.4 0. DPDP0009 54,600 663 5,62.6 595.5 595.5 595.6 0. DPDP000 56,03 674 5,530.5 595.6 595.6 595.7 0. In feet above mouth TABLE 5 DUPAGE COUNTY DATA DES PLAINES RIVER (DPDP)

FLOODING SOURCE CROSS SECTION Sawmill Creek Tributary No. 3 (DPDP) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPDP00 978 368.5 595.2 595.2 595.4 0.2 DPDP002 2,208 3 00 5.6 603. 603. 603. 0.0 DPDP003 2,633 57 260 2. 68. 68. 68. 0.0 DPDP004 4,775 337.7 637.4 637.4 637.5 0. DPDP005 6,269 20 44 3.0 652.0 652.0 652.0 0.0 DPDP006 6,436 80 775 0.7 652.4 652.4 652.4 0.0 DPDP007 7,299 2 37 4. 657.5 657.5 657.6 0. DPDP008 8,464 53 36 3. 670.3 670.3 670.4 0. DPDP009 9,023 48 80 5.2 67.4 67.4 67.5 0. DPDP0020 0,9 67 6 3.6 688.4 688.4 688.5 0. DPDP002,677 66 78 4.4 700.4 700.4 700.4 0.0 DPDP0022 2,4 228 459 0.9 703.5 703.5 703.5 0.0 DPDP0023 3,37 42.4 706.0 706.0 706. 0. DPDP0024 3,630 32 56. 706.4 706.4 706.5 0. In feet above confluence with Des Plaines River TABLE 5 DUPAGE COUNTY DATA SAWMILL CREEK TRIBUTARY NO. 3 (DPDP)

FLOODING SOURCE CROSS SECTION 79th Street Ditch (DPFC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPFC000 75 230 725 0.2 690. 690. 690.2 0. DPFC0002 355 92 27.3 690.5 690.5 690.6 0. DPFC0003 85 03 66 2. 69.5 69.5 69.6 0. DPFC0004,678 323 499 0.3 69.6 69.6 69.7 0. DPFC0005,80 36 47 3.0 69.7 69.7 69.8 0. DPFC0006 2,076 36 55 2.5 692.4 692.4 692.5 0. DPFC0007 2,838 37 70.5 693.5 693.5 693.6 0. DPFC0008 2,98 29 45 2.3 694.0 694.0 694. 0. DPFC0009 3,89 30 5.5 695.2 695.2 695.3 0. In feet above county boundary TABLE 5 DUPAGE COUNTY DATA 79TH STREET DITCH (DPFC)

FLOODING SOURCE CROSS SECTION Plainfield Road Ditch (DPFC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPFC000 09 286 3,050 0. 693.3 693.3 693.4 0. DPFC00,9 53 245 0.8 693.3 693.3 693.4 0. DPFC002,64 63 323 0.6 695.6 695.6 695.6 0.0 DPFC003,799 64 404 0.4 695.6 695.6 695.6 0.0 DPFC004 2,043 35 67 2.4 696.8 696.8 696.8 0.0 DPFC005 2,23 65 02.6 696.9 696.9 697.0 0. DPFC006 2,448 75 95.6 697.3 697.3 697.3 0.0 DPFC007 2,808 34 39 2.9 698.7 698.7 698.7 0.0 DPFC008 3,08 32 50 2.3 699.3 699.3 699.3 0.0 DPFC009 3,398 27 6.8 699.5 699.5 699.5 0.0 DPFC0020 3,708 80 333 0.3 70.4 70.4 70.4 0.0 DPFC002 3,958 34 0.0 70.4 70.4 70.4 0.0 DPFC0022 4,85 265,220 0. 702.0 702.0 702.0 0.0 DPFC0023 4,35 59 846 0. 704.5 704.5 704.5 0.0 DPFC0024 4,689 7 55.9 705.2 705.2 705.2 0.0 DPFC0025 4,904 23 7.2 705.3 705.3 705.3 0.0 DPFC0026 5,394 330 372 0.2 705.3 705.3 705.3 0.0 In feet above county boundary TABLE 5 DUPAGE COUNTY DATA PLAINFIELD ROAD DITCH (DPFC)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE Plainfield Road Ditch (DPFC) DPFC0027 5,898 53 23 0.7 705.6 705.6 705.7 0. DPFC0028 6,068 35 20 0.9 705.8 705.8 705.8 0.0 In feet above county boundary TABLE 5 DUPAGE COUNTY DATA PLAINFIELD ROAD DITCH (DPFC)

FLOODING SOURCE CROSS SECTION 63rd Street Ditch (DPFC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPFC0029,037 0 253 3.2 670.6 670.6 670.6 0.0 DPFC0030 3,57 50 8 2.9 675.2 675.2 675.2 0.0 DPFC003 4,762 00 546.9 683.3 683.3 683.3 0.0 DPFC0032 8,337 83 78 4. 70.8 70.8 70.9 0. DPFC0033 9,755 67 242 3.0 72.0 72.0 72. 0. DPFC0034 0,284 288 870 0.8 74.4 74.4 74.5 0. DPFC0035 2,650 200 709 0.5 723.8 723.8 723.9 0. In feet above county boundary TABLE 5 DUPAGE COUNTY DATA 63RD STREET DITCH (DPFC)

FLOODING SOURCE CROSS SECTION Flagg Creek (DPFC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPFC0036 48,845 83 34.2 72.3 72.3 72.4 0. DPFC0037 49,244 34 08 3. 73.5 73.5 73.6 0. DPFC0038 49,796 26 02 2.8 75.7 75.7 75.8 0. DPFC0039 50,360 2 72 90. 78.6 78.6 78.7 0. In feet above mouth 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA FLAGG CREEK (DPFC)

FLOODING SOURCE CROSS SECTION 59th Street Ditch (DPFC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPFC0040 225 32 23.7 67.2 67.2 67.3 0. DPFC004 960 3 25 7.8 675.2 675.2 675.3 0. DPFC0042,250 42 60 3. 677.2 677.2 677.3 0. DPFC0043,475 5 37 4.8 678.3 678.3 678.4 0. In feet above county boundary TABLE 5 DUPAGE COUNTY DATA 59TH STREET DITCH (DPFC)

FLOODING SOURCE CROSS SECTION South Unnamed Creek (DPWL) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPWL000 34,29 200 597.5 662. 662. 662. 0.0 DPWL0002 35,900 299,08 0.8 666.4 666.4 666.4 0.0 2 DPWL0003 37,357 206 629.3 666.7 666.7 666.7 0.0 DPWL0004 37,57 0 309 2.7 666.8 666.8 666.8 0.0 DPWL0005 38,248 57 93 2.2 669. 669. 669.2 0. DPWL0006 39,05 204 692 0.6 669.4 669.4 669.5 0. DPWL0007 39,8 37 83 0.5 669.4 669.4 669.5 0. In feet above confluence with Des Plaines River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA SOUTH UNNAMED CREEK (DPWL)

FLOODING SOURCE CROSS SECTION North Unnamed Creek (DPWL) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DPWL0008 33,672 2 409 732 2.2 663.8 663.8 663.8 0.0 DPWL0009 33,952 208 467 0.9 664.3 664.3 664.3 0.0 DPWL000 35,922 560 2 2.7 665.8 665.8 665.8 0.0 DPWL00 36,22 90 78.6 666.5 666.5 666.5 0.0 In feet above confluence with Des Plaines River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA NORTH UNNAMED CREEK (DPWL)

FLOODING SOURCE CROSS SECTION Spring Brook No. 2 (DUSG) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE DUSG000 7,272 33 679.4 657.0 657.0 657. 0. DUSG0002 2,42 95 363 2.6 659.0 659.0 659. 0. DUSG0003 25,700 33 946.0 668.5 668.5 668.6 0. DUSG0004 28,095 362,667 0.6 668.7 668.7 668.8 0. DUSG0005 3,75 227 448.6 67.5 67.5 67.6 0. DUSG0006 34,208 300 923 0.8 675.3 675.3 675.4 0. DUSG0007 39,330 855 3,064 0. 68.8 68.8 68.9 0. DUSG0008 40,832 35 335. 682.0 682.0 682. 0. DUSG0009 42,286 87 286.3 682.3 682.3 682.4 0. DUSG000 42,44 228 20.7 684.5 684.5 684.6 0. DUSG00 44,308 20 376 0.5 684.9 684.9 685.0 0. DUSG002 45,425 25 525 0.4 685.0 685.0 685. 0. DUSG003 45,578 256,256 0.2 687. 687. 687.2 0. DUSG004 48,48 3 250 0.6 687.2 687.2 687.3 0. In feet above confluence with West Branch DuPage River TABLE 5 DUPAGE COUNTY DATA SPRING BROOK NO. 2 (DUSG)

FLOODING SOURCE CROSS SECTION Armitage Ditch (EBAR) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBAR000,452 67 80 4.0 707.8 707.8 707.9 0. EBAR0002 2,006 24 83 8.6 70.9 70.9 70.9 0.0 EBAR0003 2,899 54 57 4.6 78.6 78.6 78.6 0.0 EBAR0004 3,50 8 36 2.3 720.8 720.8 720.8 0.0 EBAR0005 3,992 47 69 4.2 722. 722. 722. 0.0 EBAR0006 4,499 27 56.4 725.9 725.9 726.0 0. EBAR0007 5,423 254 587.2 733.2 733.2 733.3 0. EBAR0008 5,940 260 979 0.4 733.5 733.5 733.6 0. EBAR0009 6,579 290 904 0.5 733.5 733.5 733.6 0. EBAR000 7,455 40 92 2.3 737.6 737.6 737.7 0. EBAR00 8,920 35 00 4.3 74. 74. 74. 0.0 EBAR002 0,225 2 53 5.7 752.4 752.4 752.5 0. EBAR003 0,620 70 548 0.6 758.6 758.6 758.6 0.0 EBAR004,200 303,074 0.3 760.0 760.0 760. 0. EBAR005,690 226 477 0.5 760. 760. 760. 0.0 In feet above confluence with East Branch DuPage River TABLE 5 DUPAGE COUNTY DATA ARMITAGE DITCH (EBAR)

FLOODING SOURCE CROSS SECTION Armitage Fork (EBAR) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBAR006,452 50 8 740.5 740.5 740.5 740.5 0.0 EBAR007 2,0 9 2 758.2 758.2 758.2 758.2 0.0 In feet above confluence with Armitage Ditch TABLE5 DUPAGE COUNTY DATA ARMITAGE FORK (EBAR)

FLOODING SOURCE CROSS SECTION Crabtree Creek (EBCR) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBCR000 655 42 85 4.0 655.0 655.0 655.0 0.0 EBCR0002 3,655 40 239 3. 683.3 683.3 683.3 0.0 EBCR0003 5,037 4 03 7.2 698.5 698.5 698.5 0.0 EBCR0004 6,039 94 246 3.0 73. 73. 73. 0.0 In feet above confluence with East Branch DuPage River TABLE 5 DUPAGE COUNTY DATA CRABTREE CREEK (EBCR)

FLOODING SOURCE CROSS SECTION East Branch DuPage River (EBEB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBEB000 39,546 698 2,239.4 652.3 652.3 652.4 0. EBEB0002 42,553 40 876 3.4 655. 655. 655.2 0. EBEB0003 46,276 267,636.8 657.9 657.9 658.0 0. EBEB0004 5,84 530 3,00.0 660.2 660.2 660.2 0.0 EBEB0005 54,64 3 623 4.7 662. 662. 662.2 0. EBEB0006 55,725 0 694 4.2 663.3 663.3 663.3 0.0 EBEB0007 56,77 7 736 3.9 663.7 663.7 663.8 0. EBEB0008 58,385 857 2,852.0 664.5 664.5 664.6 0. EBEB0009 58,527 857 2,87.0 664.5 664.5 664.6 0. EBEB000 59,387 296 3,884 0.6 665.0 665.0 665. 0. EBEB00 60,050 90 728 4.0 665.7 665.7 665.7 0.0 EBEB002 60,23 35 487 6.0 665.8 665.8 665.8 0.0 EBEB003 6,326 9 776 3.7 668. 668. 668. 0.0 EBEB004 62,802 06 787 3.7 669.2 669.2 669.2 0.0 EBEB005 64,0 205,366.6 670.4 670.4 670.4 0.0 EBEB006 64,347 53 2,323 0.9 670.5 670.5 670.6 0. EBEB007 65,098 569 3,82 0.7 670.6 670.6 670.7 0. In feet above confluence with West Branch DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA EAST BRANCH DUPAGE RIVER (EBEB)

FLOODING SOURCE CROSS SECTION East Branch DuPage River (EBEB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBEB008 66,245 273,368.6 67.0 67.0 67. 0. EBEB009 67,569 535 2,234.0 67.6 67.6 67.7 0. EBEB0020 70,769 56 2,399 0.9 673.8 673.8 673.9 0. EBEB002 72,500 22 653 3.4 674.3 674.3 674.4 0. EBEB0022 74,465 368,600.4 676.4 676.4 676.4 0.0 2 EBEB0023 76,235,030,667.3 676.7 676.7 676.8 0. EBEB0024 77,448 200 387 5.7 676.8 676.8 676.9 0. EBEB0025 77,785 60 797 2.0 677.3 677.3 677.4 0. EBEB0026 80,229,008 2,662 0.6 678.4 678.4 678.4 0.0 EBEB0027 83,043 55 273 5.3 680.3 680.3 680.4 0. EBEB0028 83,98 60 346 4. 682. 682. 682.2 0. EBEB0029 85,337 743 2,597 0.6 682.8 682.8 682.9 0. EBEB0030 87,732 460,760 0.8 683.4 683.4 683.5 0. EBEB003 89,69 7 605 2.4 684.5 684.5 684.6 0. EBEB0032 90,56 658 2,629 0.5 684.9 684.9 685.0 0. EBEB0033 9,769 790 770.9 686.7 686.7 686.8 0. EBEB0034 92,385 759 2,763 0.5 686.9 686.9 687.0 0. In feet above confluence with West Branch DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA EAST BRANCH DUPAGE RIVER (EBEB)

FLOODING SOURCE CROSS SECTION East Branch DuPage River (EBEB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBEB0035 94,068 544 2,36 0.6 687.0 687.0 687. 0. EBEB0036 97,486 28 48 3.0 687.6 687.6 687.7 0. 2 EBEB0037 98,482 79 34 4.2 689.8 689.8 689.8 0.0 EBEB0038 99,487 840 642 2.2 69.6 69.6 69.7 0. EBEB0039 0,248 690 3,480 0.4 69.8 69.8 69.9 0. EBEB0040 06,067 329 928. 692.5 692.5 692.6 0. EBEB004 08,486 338 399 2.5 693.6 693.6 693.7 0. EBEB0042 3,097 62 33 2.6 697.7 697.7 697.8 0. EBEB0043 6,8 29 30 2.7 700.6 700.6 700.7 0. EBEB0044 7,099 57 9 3.9 702.0 702.0 702. 0. EBEB0045 8,935,43 6,429 0. 70.5 70.5 70.6 0. EBEB0046 22,553 692 3,98 0. 72.2 72.2 72.3 0. In feet above confluence with West Branch DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA EAST BRANCH DUPAGE RIVER (EBEB)

FLOODING SOURCE CROSS SECTION East Branch Tributary No. 2 (EBE2) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBE2000 494 476 2,255 2.3 699.0 699.0 699. 0. EBE200,073 323 58 2.8 699.4 699.4 699.5 0. EBE2002,50 220 32 7.5 702. 702. 702.2 0. EBE2003,564 548 93 2. 705. 705. 705.2 0. EBE2004,953 0 279 3.4 705.7 705.7 705.8 0. EBE2005 2,35 73 20.4 707.4 707.4 707.5 0. EBE2006 2,379 44 550.8 709.7 709.7 709.8 0. EBE2007 2,834 26 40 2.5 70.2 70.2 70.3 0. EBE2008 3,077 89 326 2.8 70.6 70.6 70.7 0. EBE2009 3,677 96 404.8 74.6 74.6 74.7 0. EBE200 3,925 54 245 2.8 74.7 74.7 74.8 0. EBE20 4,024 54 77 0.9 76.9 76.9 77.0 0. EBE202 4,207 44 524. 76.9 76.9 77.0 0. EBE203 4,376 97 294 6.7 77.0 77.0 77. 0. EBE204 4,469 35 543 2.8 79.9 79.9 720.0 0. EBE205 4,85 30 59 5.6 720.4 720.4 720.5 0. EBE206 4,998 93 220.8 722.6 722.6 722.7 0. In feet above Confluence with East Branch DuPage River TABLE 5 DUPAGE COUNTY DATA EAST BRANCH TRIBUTARY NO. 2 (EBE2)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE East Branch Tributary No. 2 (EBE2) EBE207 5,33 28 260.0 722.9 722.9 723.0 0. EBE208 5,576 5 272. 723.0 723.0 723. 0. EBE209 6,049 94 344. 723.2 723.2 723.3 0. In feet above Confluence with East Branch DuPage River TABLE 5 DUPAGE COUNTY DATA EAST BRANCH TRIBUTARY NO. 2 (EBE2)

FLOODING SOURCE CROSS SECTION East Branch Tributary No. 3 (EBEB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBEB0047 684 2 64 239.4 670.2 670.2 670.2 0.0 EBEB0048,03 2 84 97 3.4 674.9 674.9 674.9 0.0 EBEB0049,426 0 273.2 686.0 686.0 686. 0. EBEB0050,754 57 26 2.6 686. 686. 686.2 0. EBEB005,890 57 62 5.2 686.5 686.5 686.5 0.0 EBEB0052 2,63 25 264.2 699. 699. 699.2 0. EBEB0053 3,263 9 98. 73.7 73.7 73.7 0.0 In feet above confluence with East Branch DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA EAST BRANCH TRIBUTARY NO. 3 (EBEB)

FLOODING SOURCE CROSS SECTION East Branch DuPage River Tributary No. 4 (EBGL) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBGL000 557 28 94 5.9 684.5 684.5 684.5 0.0 EBGL0002 2,362 93 267 2. 700.4 700.4 700.5 0. EBGL0003 3,293 25 367.3 709.9 709.9 709.9 0.0 EBGL0004 4,398 58 8 2.7 75.9 75.9 75.9 0.0 EBGL0005 4,684 2 0 327.5 728.2 728.2 728.2 0.0 EBGL0006 5,72 82 78 2.8 729.9 729.9 729.9 0.0 In feet above confluence with East Branch DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA EAST BRANCH TRIBUTARY NO. 4 (EBGL)

FLOODING SOURCE CROSS SECTION East Branch Tributary No. 5 (EBWI) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBWI000,390 2 2 2 678.7 2 2 2 EBWI0002 2,452 2 2 2 68.5 2 2 2 2 2 2 2 2 2 EBWI0003 3,499 686.6 2 2 2 2 2 2 EBWI0004 4,363 689.5 2 2 2 2 2 2 EBWI0005 5,240 69.4 EBWI0006 6,566 24 534.6 70.0 70.0 70. 0. EBWI0007 7,05 33 94 9.2 702.6 702.6 702.6 0.0 2 2 2 2 2 2 EBWI0008 8,579 74.2 2 2 2 2 2 2 EBWI0009 9,244 76.7 2 2 2 2 2 2 EBWI000 9,862 79.0 EBWI00 0,39 2 2 2 79.7 2 2 2 EBWI002 2,220 2 2 2 724.2 2 2 2 In feet above confluence with East Branch DuPage River 2 Data not available TABLE 5 DUPAGE COUNTY DATA EAST BRANCH TRIBUTARY NO. 5 (EBWI)

FLOODING SOURCE CROSS SECTION St. Procopius Creek (EBE6) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBE6000 8,498 2 62 5.2 704.9 704.9 704.9 0.0 EBE60002 8,87 40 44 2.2 708.6 708.6 708.6 0.0 EBE60003 9,724 04 224.4 74.4 74.4 74.5 0. EBE60004 0,270 38 70 4.6 77.8 77.8 77.8 0.0 In feet above confluence with East Branch DuPage River TABLE 5 DUPAGE COUNTY DATA ST. PROCOPIUS CREEK (EBE6)

FLOODING SOURCE CROSS SECTION Lacey Creek (EBLA) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBLA000 686 3 285 873.0 676.7 2 676.0 676. 0. EBLA0002 2,483 85 623.4 677.0 677.0 677. 0. EBLA0003 4,382 3 285,597 0.5 680.5 680.5 680.6 0. EBLA0004 4,804 3 700 956 0.9 680.7 680.7 680.8 0. EBLA0005 5,068 3 445 584.5 68.7 68.7 68.8 0. EBLA0006 6,09 450 465.9 683.5 683.5 683.6 0. EBLA0007 7,579 280 582.5 689.2 689.2 689.3 0. EBLA0008 8,760 25,64 0.4 69.5 69.5 69.5 0.0 EBLA0009 9,27 90 638. 69.9 69.9 69.9 0.0 EBLA000 0,65 60 35 5. 692.0 692.0 692.0 0.0 EBLA00 0,894 70 427.6 695. 695. 695. 0.0 EBLA002,989 85 439.6 696.5 696.5 696.5 0.0 EBLA003 2,972 20,477 0.5 696.7 696.7 696.7 0.0 EBLA004 4,000,020 3,42 0.2 696.8 696.8 696.8 0.0 EBLA005 5,66 675 4,703 0. 696.8 696.8 696.8 0.0 EBLA006 6,83 25 540.0 697.2 697.2 697.3 0. EBLA007 7,362 00 38.4 698. 698. 698.2 0. EBLA008 7,785 55 373.4 699.0 699.0 699. 0. In feet above confluence with East Branch DuPage River 2 Elevation computed without consideration of backwater effects from East Branch DuPage River 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA LACEY CREEK (EBLA)

FLOODING SOURCE CROSS SECTION Lacey Creek (EBLA) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBLA009 8,049 60 67 2.9 702.3 702.3 702.3 0.0 In feet above confluence with East Branch DuPage River 2 Elevation computed without consideration of backwater effects from East Branch DuPage River 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA LACEY CREEK (EBLA)

FLOODING SOURCE CROSS SECTION Prentiss Creek (EBPR) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBPR000 6,589 69 585.7 664.8 664.8 664.8 0.0 EBPR0002 3,600 2 20 603.5 697.9 697.9 697.9 0.0 EBPR0003 4,395 2 00 49 2.2 699.7 699.7 699.7 0.0 EBPR0004 6,520 50 335 2.7 7.7 7.7 7.7 0.0 EBPR0005 7,057 45 08 8.3 77.7 77.7 77.7 0.0 EBPR0006 7,694 60 297 3.0 720.9 720.9 720.9 0.0 EBPR0007 8,280 2 30,3 0.5 722.2 722.2 722.2 EBPR0008 9,22 2 85 44.4 722.7 722.7 722.7 EBPR0009 2,05 2 95 409.5 730.0 730.0 730.0 0.0 EBPR000 22,848 2 75 398.5 744. 744. 744. 0.0 EBPR00 23,5 45 96 6.3 744. 744. 744. 0.0 In feet above East Branch DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA PRENTISS CREEK (EBPR)

FLOODING SOURCE CROSS SECTION Rott Creek (EBRC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBRC000,73 256 58 4.7 664.5 2 658.9 2 659.0 0. EBRC0002 2,505 08 305 2.4 668.4 668.4 668.4 0.0 EBRC0003 3,206 47 35 5.5 670.0 670.0 670. 0. EBRC0004 4,08 44 2 6.0 675.5 675.5 675.5 0.0 EBRC0005 4,330 37 24 5.8 677. 677. 677. 0.0 EBRC0006 6,390 59 5 4.8 687.2 687.2 687.3 0. EBRC0007 7,204 65 85 3.9 692. 692. 692.2 0. EBRC0008 7,743 94 249 2.9 694.2 694.2 694.3 0. EBRC0009,200 95 53.4 7.4 7.4 7.5 0. EBRC000 2,25 50 33 5.4 77.7 77.7 77.7 0.0 EBRC00 2,425 54 425.7 720.8 720.8 720.8 0.0 EBRC002 3,90 20 333 2.2 722.2 722.2 722.3 0. EBRC003 3,407 20 399.8 722.5 722.5 722.6 0. EBRC004 3,978 83 245 2. 722.8 722.8 722.8 0.0 EBRC005 4,25 86 585 0.9 724.6 724.6 724.6 0.0 EBRC006 4,465 278,205 0.4 724.6 724.6 724.6 0.0 EBRC007 5,498 354,068 0.5 724.6 724.6 724.6 0.0 EBRC008 6,62 95 532 0.9 724.7 724.7 724.7 0.0 In feet above confluence with East Branch DuPage River 2 Elevations computed without consideration of backwater effects from East Branch DuPage River TABLE 5 DUPAGE COUNTY DATA ROTT CREEK (EBRC)

FLOODING SOURCE CROSS SECTION St. Joseph Creek (EBSJ) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE 2 EBSJ000 897 80 44 3. 668.6 667.8 667.9 0. EBSJ0002,256 67 623 2.2 669.2 669.2 669.2 0.0 EBSJ0003,49 4 390 3.5 669.2 669.2 669.2 0.0 EBSJ0004,736 4 435 3. 669.6 669.6 669.6 0.0 EBSJ0005 2,42 54 398 3.4 670.0 670.0 670.0 0.0 EBSJ0006 3,73 47 558 2.4 67.0 67.0 67. 0. EBSJ0007 3,537 83 376 3.5 67.0 67.0 67.0 EBSJ0008 3,960 64 387 3.4 67.6 67.6 67.7 0. EBSJ0009 4,488 20 479 2.8 673.7 673.7 673.8 0. 4 EBSJ000 5,06 49 452 2.9 674. 674. 674.2 0. EBSJ00 5,334 47 8 7.3 674.4 674.4 674.4 0.0 4 EBSJ002 5,492 52,050.3 675.6 675.6 675.6 0.0 4 EBSJ003 5,702 03 595 2.2 676.4 676.4 676.5 0. EBSJ004 6,547 27 479 2.7 676.5 676.5 676.6 0. EBSJ005 6,969 47 267 4.8 676.7 676.7 676.8 0. EBSJ006 7,920 69 332 3.9 678.4 678.4 678.5 0. EBSJ007 8,923 70 375 3.4 680.0 680.0 680. 0. In feet above confluence with East Branch DuPage River 2 Elevation considered without backwater effects from East Branch DuPage River 3 Floodway coincident with channel banks 4 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA ST. JOSEPH CREEK (EBSJ)

FLOODING SOURCE CROSS SECTION St. Joseph Creek (EBSJ) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBSJ008 9,29 52 329 3.9 680.5 680.5 680.6 0. EBSJ009 0,02 50 30 4.2 68.5 68.5 68.5 0.0 EBSJ0020 0,400 50 30 4.2 68.9 68.9 68.9 0.0 EBSJ002 2,59 50 450 2.9 684.0 684.0 684.0 0.0 EBSJ0022 2,828 40,3.2 688.0 688.0 688. 0. EBSJ0023 4,59 60 464 2.7 690.8 690.8 690.9 0. EBSJ0024 5,054 70 446 2.8 692.7 692.7 692.8 0. EBSJ0025 6,06 48 745.7 694.7 694.7 694.8 0. EBSJ0026 8,304 85 844.5 696.8 696.8 696.9 0. EBSJ0027 9,42 05 876.4 697.4 697.4 697.5 0. EBSJ0028 9,834 40 730.7 697.9 697.9 698.0 0. EBSJ0029 20,362 90,07.2 698.4 698.4 698.5 0. EBSJ0030 2,589 0 504 2.5 699.7 699.7 699.8 0. EBSJ003 22,223 05 239 5.2 700.2 700.2 700.3 0. EBSJ0032 22,440 45 78.7 70.3 70.3 70.4 0. EBSJ0035 27,625 3 89 3.3 709.8 709.8 709.8 0.0 EBSJ0036 27,998 3 98 3.0 70. 70. 70. 0.0 In feet above confluence with East Branch DuPage River 2 Elevation considered without backwater effects from East Branch DuPage River 3 Floodway coincident with channel banks 4 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA ST. JOSEPH CREEK (EBSJ)

FLOODING SOURCE CROSS SECTION St. Joseph Creek (EBSJ) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE 3 EBSJ0037 28,689 93 3.2 75.0 75.0 75.0 0.0 EBSJ0038 29,58 5 228.3 75.3 75.3 75.4 0. EBSJ0039 30,74 46 342.9 78. 78. 78.2 0. EBSJ0040 3,582 8 352.9 79.5 79.5 79.6 0. EBSJ004 32,253 98 298 2.2 79.8 79.8 79.9 0. EBSJ0042 33,89 83 564.2 72.0 72.0 72. 0. EBSJ0043 35,047 30,435 0.4 726. 726. 726.2 0. EBSJ0044 35,772 70 98 2.5 727.6 727.6 727.7 0. EBSJ0045 36,474 24 36.3 730.6 730.6 730.7 0. EBSJ0046 38,687 53 85 2.2 734. 734. 734.2 0. In feet above confluence with East Branch DuPage River 2 Elevation considered without backwater effects from East Branch DuPage River 3 Floodway coincident with channel banks 4 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA ST. JOSEPH CREEK (EBSJ)

FLOODING SOURCE CROSS SECTION Tributary (A) (EBSJ) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBSJ0047 97 7 22 0.2 670.8 2 670.5 670.5 0.0 EBSJ0048 265 89 45.6 674.3 674.3 674.3 0.0 EBSJ0049 355 3 33 7. 675.3 675.3 675.3 0.0 EBSJ0050 476 5 264 0.9 678.6 678.6 678.6 0.0 EBSJ005 775 5 29 7.9 679.6 679.6 679.6 0.0 EBSJ0052,227 65 22.9 682.5 682.5 682.5 0.0 EBSJ0053,484 59 27. 684.3 684.3 684.3 0.0 EBSJ0054 2,39 5 65 3.5 689.5 689.5 689.5 0.0 EBSJ0055 2,566 3 80 52 0.4 696. 696. 696.2 0. EBSJ0056 3,56 88 32 3.3 699.4 699.4 699.5 0. EBSJ0057 4,030 3 20 65.6 70.8 70.8 70.8 0.0 EBSJ0058 5,302 50 29 3.6 728. 728. 728. 0.0 In feet above confluence with St. Joseph Creek 2 Elevation computed without consideration of backwater effects from St. Joseph Creek 3 Actual floodway width cannot be shown on the FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA TRIBUTARY (A) (EBSJ)

FLOODING SOURCE CROSS SECTION Tributary 2 (B) (EBSJ) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBSJ0059 95 65 530 0.5 685.2 685.2 685.3 0. EBSJ0060 935 70 32 0.9 685.2 685.2 685.3 0. EBSJ006,662 2 04 86.5 685.4 685.4 685.5 0. EBSJ0062,780 2 75 68 4. 687.3 687.3 687.4 0. EBSJ0063 2,02 3 3 9.0 695.0 695.0 695.0 0.0 EBSJ0064 2,58 25 66 4.2 697.2 697.2 697.2 0.0 EBSJ0065 2,42 9 50 5.5 699.8 699.8 699.8 0.0 In feet above confluence with St. Joseph Creek 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain. TABLE 5 DUPAGE COUNTY DATA TRIBUTARY 2 (B) (EBSJ)

FLOODING SOURCE CROSS SECTION North Branch St. Joseph Creek (EBSJ) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBSJ0066 264 23 95 4.9 73. 73. 73.2 0. EBSJ0067 898 2 69 6.7 75.6 75.6 75.6 0.0 EBSJ0068,636 60 232 2.0 72.9 72.9 72.9 0.0 EBSJ0069 2,265 2 267.7 722.3 722.3 722.3 0.0 EBSJ0070 2,497 224 437. 722.5 722.5 722.6 0. EBSJ007 2,957 39 353.3 723.2 723.2 723.3 0. EBSJ0072 3,432 27 76 6. 723.9 723.9 724.0 0. EBSJ0073 3,749 2 00 832 0.6 725.9 725.9 725.9 0.0 In Feet above confluence with St. Joseph Creek 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA NORTH BRANCH ST. JOSEPH CREEK (EBSJ)

FLOODING SOURCE CROSS SECTION South Branch St. Joseph Creek (EBSJ) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBSJ0074 2 288,528 0.2 2 78.2 78.2 78.3 0. EBSJ0075 58 438 2,294 0.2 2 78.2 78.2 78.3 0. 2 EBSJ0076 986 77,080 0.3 78.2 78.2 78.3 0. EBSJ0077,320 23 924 0.4 78.3 78.3 78.4 0. EBSJ0078,465 305,44 0.2 78.3 78.3 78.4 0. EBSJ0079,80 39 265.3 78.9 78.9 79.0 0. EBSJ0080 2,474 80 47 2.3 723.8 723.8 723.8 0.0 EBSJ008 3,050 39 52 6.4 726.9 726.9 726.9 0.0 EBSJ0082 3,684 2 9 2.8 73.3 73.3 73.4 0. EBSJ0083 4,328 88 296. 739.2 739.2 739.3 0. EBSJ0084 4,380 93 99.7 739.3 739.3 739.4 0. EBSJ0085 4,48 87 37.0 739.4 739.4 739.5 0. EBSJ0086 5,06 43 08 3. 743.4 743.4 743.5 0. EBSJ0087 5,069 64 42 2.4 744.0 744.0 744. 0. EBSJ0088 5,22 84 94.7 744.4 744.4 744.5 0. EBSJ0089 5,388 02 209.6 745.7 745.7 745.8 0. EBSJ0090 6,766 00 969 0.3 747.8 747.8 747.9 0. In feet above confluence with St. Joseph Creek 2 Backwater from St. Joseph Creek TABLE 5 DUPAGE COUNTY DATA SOUTH BRANCH ST. JOSEPH CREEK (EBSJ)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE South Branch St. Joseph Creek (EBSJ) EBSJ009 7,7 204 330.0 747.8 747.8 747.9 0. EBSJ0092 7,595 79 46 0.8 748.0 748.0 748. 0. In feet above confluence with St. Joseph Creek 2 Backwater from St. Joseph Creek TABLE 5 DUPAGE COUNTY DATA SOUTH BRANCH ST. JOSEPH CREEK (EBSJ)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE St. Joseph Creek Tributary (EBSJ) EBSJ0093 744 39 52.9 728.4 728.4 728.5 0. EBSJ0094 2,804 5 44.3 73.3 73.3 73.4 0. In feet above confluence with St. Joseph Creek TABLE 5 DUPAGE COUNTY DATA ST. JOSEPH CREEK TRIBUTARY (EBSJ)

FLOODING SOURCE CROSS SECTION Unnamed Stream North of 22nd Street (EBTS) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE EBTS000,298 2 2 92 4.2 683.2 682.9 682.9 0.0 EBTS0002,838 2 32 205.9 686.6 686.6 686.7 0. 2 EBTS0003 2,598 27 76 2.2 689.0 689.0 689.0 0.0 EBTS0004 3,99 89 65 2. 690.8 690.8 690.9 0. 2 EBTS0005 3,70 4 73 2.0 692.4 692.4 692.5 0. 2 EBTS0006 4,250 4 88.8 694.7 694.7 694.8 0. EBTS0007 4,800 2 73 77 4.5 698.8 698.8 698.9 0. EBTS0008 5,68 34 92 3.2 704.5 704.5 704.6 0. In feet above confluence with East Branch DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA UNNAMED STREAM NORTH OF 22ND STREET (EBTS)

FLOODING SOURCE CROSS SECTION Brewster Creek (FRBC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE FRBC000 23,490 520 5,063 0. 773.8 773.8 773.8 0.0 FRBC0002 24,880 50,36 0.2 773.8 773.8 773.8 0.0 FRBC0003 29,835 8 230.9 785.8 785.8 785.9 0. In feet above confluence with West Branch DuPage River TABLE 5 DUPAGE COUNTY DATA BREWSTER CREEK (FRBC)

FLOODING SOURCE CROSS SECTION Norton Creek (FRNC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE FRNC000 20,274 0 384.7 74.5 74.5 74.6 0. FRNC0002 2,65 22 598. 74.8 74.8 74.9 0. FRNC0003 22,778 362 802 0.8 742. 742. 742.2 0. FRNC0004 24,00 76 60 4.0 742.6 742.6 742.7 0. FRNC0005 26,087 283 665.0 745.3 745.3 745.4 0. In feet above confluence with Fox River TABLE 5 DUPAGE COUNTY DATA NORTON CREEK (FRNC)

FLOODING SOURCE CROSS SECTION Norton Creek Tributary (FRNC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE FRNC0006,005 30 959 0.4 74.4 2 74.4 74.5 0. FRNC0007,936 87 335. 743.0 743.0 743. 0. FRNC0008 3,200 86 35. 743.2 743.2 743.3 0. FRNC0009 4,245 209 50 0.7 744.3 744.3 744.4 0. FRNC000 4,575 2 53 6.8 744.8 744.8 744.9 0. FRNC00 5,922 95 279.3 746. 746. 746.2 0. FRNC002 7,779 3 289 705 0.5 747.0 747.0 747.0 0.0 In feet above confluence with Norton Creek 2 Elevation computed without consideration of backwater effects from Norton Creek 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA NORTON CREEK TRIBUTARY (FRNC)

FLOODING SOURCE CROSS SECTION Waubansee Creek (FRWA) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE FRWA000 50 70 2 2 67.2 67.2 67.2 0.0 FRWA0002,507 290 2 2 672. 672. 672. 0.0 2 2 FRWA0003 2,856 30 672.4 672.4 672.4 0.0 2 2 FRWA0004 4,53 75 672.6 672.6 672.6 0.0 2 2 FRWA0005 5,507 40 673. 673. 673. 0.0 2 2 FRWA0006 6,407 00 674.0 674.0 674.0 0.0 2 2 FRWA0007 7,03 05 674.9 674.9 674.9 0.0 FRWA0008 8,57 80 2 2 675.9 675.9 675.9 0.0 FRWA0009 9,407 70 2 2 677.4 677.4 677.4 0.0 In feet above county boundary 2 Data not available TABLE 5 DUPAGE COUNTY DATA WAUBANSEE CREEK (FRWA)

FLOODING SOURCE CROSS SECTION Bronswood Cemetary Tributary (SCBW) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCBW000 30 2 37 43.0 652.0 65.7 65.8 0. SCBW0002 90 65 87 5.2 658.5 658.5 658.5 0.0 SCBW0003,690 46 2 4.0 667.2 667.2 667.3 0. SCBW0004,970 80 99 4.5 669.7 669.7 669.8 0. SCBW0005 2,750 38 6 7.3 676.3 676.3 676.3 0.0 SCBW0006 2,890 80 230 2.0 68.9 68.9 68.9 0.0 SCBW0007 3,070 00 383.2 684.0 684.0 684. 0. 2 SCBW0008 3,570 28 76 2.6 684.4 684.4 684.5 0. 2 SCBW0009 4,826 342,65 0.3 688.2 688.2 688.3 0. SCBW000 5,856 55 584 0.7 688.2 688.2 688.3 0. SCBW00 6,047 350 693 0.6 688.8 688.8 688.9 0. 2 SCBW002 6,276 33 43 0.9 688.9 688.9 689.0 0. 2 SCBW003 6,447 8 225.7 69.0 69.0 69. 0. SCBW004 7,080 29 35 6.4 69.5 69.5 69.6 0. SCBW005 7,750 2 54 25 0.9 697.4 697.4 697.5 0. In feet above confluence with Salt Creek 2 Actual floodway width cannot be shown on the FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA BRONSWOOD TRIBUTARY CEMETARY (SCBW)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE Devon Avenue Tributary (SCDA) SCDA000 3,800 2 435 739 0.3 685.5 685.5 685.6 0. SCDA0002 5,000 2 228 388 0.5 685.7 685.7 685.8 0. SCDA0003 5,200 2 302 80. 687.8 687.8 687.9 0. In feet above Salt Creek 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA DEVON AVENUE TRIBUTARY (SCDA)

FLOODING SOURCE CROSS SECTION Ginger Creek (SCGC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCGC500 60 2 2 2 655.5 655.5 655.6 0. SCGC5003 200 2 2 2 655.5 655.5 655.6 0. SCGC5006,5 2 2 2 657.0 657.0 657. 0. SCGC500 2,045 42 22 6.4 658.3 658.3 658.4 0. SCGC50 2,25 30 34 9.8 659.5 659.5 659.6 0. SCGC502 2,550 80 600 2.2 662.2 662.2 662.3 0. SCGC504 2,800 64,25. 664. 664. 664.2 0. SCGC505 3,040 335 2,58 0.6 664. 664. 664.2 0. SCGC507 3,70 63,373.0 665.4 665.4 665.5 0. SCGC508 3,935 55,334.0 655.4 655.4 655.5 0. SCGC509 4,280 58,294. 655.4 655.4 655.5 0. SCGC5020 4,565 20 900.4 655.4 655.4 655.5 0. SCGC5030 6,375 70 53.5 669.7 669.7 669.8 0. SCGC503 6,55 38 237 3.3 669.7 669.7 669.8 0. SCGC5032 6,720 47,0 0.7 669.7 669.7 669.8 0. SCGC5033 6,925 3 842 0.9 669.7 669.7 669.8 0. SCGC5035 7,260 60 37 5.3 669.7 669.7 669.8 0. SCGC5036 7,450 55 95 7.2 673.2 673.2 673.3 0. In feet above confluence with Salt Creek 2 Data not available 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA GINGER CREEK (SCGC)

FLOODING SOURCE CROSS SECTION Ginger Creek (SCGC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCGC5037 7,65 3 63 923 0.7 673.9 673.9 674.0 0. SCGC5038 7,775 230,502 0.4 673.9 673.9 674.0 0. SCGC5039 8,280 33 39 4.3 674.2 674.2 674.3 0. SCGC5040 8,60 39 76 7.7 677.3 677.3 677.4 0. SCGC504 8,740 89 624 0.9 678. 678. 678.2 0. SCGC5049 9,275 05 47.4 688.4 688.4 688.5 0. SCGC5050 9,840 75 250 2.3 688.4 688.4 688.5 0. SCGC5046 0,450 6 37 3.8 690.6 690.6 690.7 0. SCGC5067,500 80 79 2.7 695.2 695.2 695.3 0. SCGC5068,825 90 80 2.4 696.5 696.5 696.5 0.0 SCGC5053 2,320 88 385. 699.3 699.3 699.4 0. SCGC5047 5,335 4 85 0.2 699.3 699.3 699.4 0. SCGC505 6,290 55,268 0.2 699.3 699.3 699.4 0. SCGC5045 6,720 65 705 0.4 699.3 699.3 699.4 0. In feet above confluence with Salt Creek 2 Data not available 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA GINGER CREEK (SCGC)

FLOODING SOURCE CROSS SECTION Briarwood Ditch (SCGC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCGC5043 370 4,059 0.3 2 669.7 669.7 669.8 0. SCGC5069 950 2 70 6.4 2 669.7 669.7 669.8 0. SCGC5073,600 33 24 2.6 672. 672. 672.2 0. In feet above confluence with Ginger Creek 2 Elevation based on unsteady flow model TABLE 5 DUPAGE COUNTY DATA BRIARWOOD DITCH (SCGC)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE Heritage Oaks Tributary (SCGC) SCGC5044 675 493 5,333 0.0 2 699.3 699.3 699.4 0. In feet above confluence with Ginger Creek 2 Elevation based on unsteady flow model TABLE 5 DUPAGE COUNTY DATA HERITAGE OAKS TRIBUTARY (SCGC)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE Lombard Tributary (SCGC) SCGC5054 250 57 247.9 2 699.3 2 699.3 699.4 0. SCGC5056 590 48 39 3.4 70.0 2 70.0 70.0 0. In feet above confluence with Ginger Creek 2 Elevation based on unsteady flow model TABLE 5 DUPAGE COUNTY DATA LOMBARD TRIBUTARY (SCGC)

FLOODING SOURCE CROSS SECTION Mays Lake Tributary (SCGC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCGC507,400 2 2 2 672.0 2 2 2 SCGC5028,640 2 2 2 679.5 2 2 2 2 2 2 2 2 2 SCGC5026,925 683.4 SCGS5057 2,635 2 2 2 70.2 2 2 2 SCGC5058 2,70 2 2 2 70.5 2 2 2 In feet above confluence with Ginger Creek 2 Data not available TABLE 5 DUPAGE COUNTY DATA MAYS LAKE TRIBUTARY (SCGC)

FLOODING SOURCE CROSS SECTION Midwest Club Tributary (SCGC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCGC5066 450 44 22. 695.5 695.5 695.6 0. SCGC5065 975 22 72.7 695.7 695.7 695.8 0. SCGC5064,475 223 505 0.2 695.8 695.8 695.9 0. SCGC5063,795 25 67.5 695.8 695.8 695.9 0. SCGC5062 2,30 38 35 2. 697.8 697.8 697.9 0. 2 2 2 2 2 2 SCGC506 2,905 702.3 In feet above confluence with Ginger Creek 2 Data not available TABLE 5 DUPAGE COUNTY DATA MIDWEST CLUB TRIBUTARY (SCGC)

FLOODING SOURCE CROSS SECTION Spring Road Tributary (SCOB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCOB000 527 285 895 0.5 66.0 66.0 66. 0. SCOB0002,276 42 20 2.3 66. 66. 66.2 0. SCOB0003 2,0 3 28 3.8 662.5 662.5 662.6 0. SCOB0004 2,88 28 0 4.8 663.8 663.8 663.9 0. SCOB0005 2,888 65 25 2.2 666.7 666.7 666.8 0. SCOB0006 3,300 35 32 3.7 668.2 668.2 668.3 0. SCOB0007 3,550 49 459.0 67. 67. 67. 0.0 SCOB0008 3,852 226 44.0 67.2 67.2 67.2 0.0 SCOB0009 4,050 206 40.0 67.3 67.3 67.3 0.0 SCOB000 4,269 59 280.4 67.7 67.7 67.7 0.0 SCOB00 4,537 42 288.6 672.8 672.8 672.8 0.0 SCOB002 4,830 200 455 0.8 672.9 672.9 672.9 0.0 SCOB003 5,73 5 39 0. 676.8 676.8 676.8 0.0 SCOB004 6,76 80 34.2 684.6 684.6 684.7 0. SCOB005 7,224 30 24 3.2 685.2 685.2 685.3 0. SCOB006 7,800 90 653 0.6 685.4 685.4 685.5 0. SCOB007 8,353 280 766 0.4 686.2 686.2 686.3 0. In feet above confluence with Salt Creek TABLE 5 DUPAGE COUNTY DATA SPRING ROAD TRIBUTARY (SCOB)

FLOODING SOURCE CROSS SECTION Spring Brook Creek (SCSB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSB000 528,265 8,846 0. 680.6 680.6 680.7 0. SCSB0002,478 969 4,487 0.3 680.6 680.6 680.7 0. SCSB0003,795,280 4,830 0.2 680.6 680.6 680.7 0. SCSB0004 3,590 336,360 0.8 68.2 68.2 68.3 0. SCSB0005 5,772 23 67.9 683.0 683.0 683. 0. SCSB0006 6,372 234,400 0.9 683. 683. 683.2 0. SCSB0007 7,047 55 88.4 686. 686. 686.2 0. SCSB0008 7,53 48,505 0.8 686.7 686.7 686.8 0. SCSB0009 7,95 327,847 0.7 686.8 686.8 686.9 0. SCSB000 0,457 245,32. 687.8 687.8 687.9 0. SCSB00 2,929 430,80 0.7 688.2 688.2 688.3 0. SCSB002 4,236 540,277.0 688.9 688.9 689.0 0. SCSB003 6,6 30 2,30 0.6 689.6 689.6 689.7 0. SCSB004 8,338 270 2,397 0.4 703.6 703.6 703.7 0. SCSB005 20,359 85,285 0.7 704.3 704.3 704.4 0. SCSB006 23,456 2 204 654. 704.9 704.9 705.0 0. SCSB007 23,79 2 230 707.0 705.5 705.5 705.6 0. In feet above confluence with Salt Creek 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA SPRING BROOK CREEK (SCSB)

FLOODING SOURCE CROSS SECTION Spring Brook Creek (SCSB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSB008 24,58 2 00 508.4 706. 706. 706.2 0. SCSB009 24,358 2 00 80 4.0 706.4 706.4 706.5 0. 2 SCSB0020 24,497 55 475.5 708.0 708.0 708. 0. SCSB002 24,660 46 85 3.9 708.4 708.4 708.5 0. 2 SCSB0022 24,82 270,23 0.6 708.8 708.8 708.9 0. SCSB0023 26,43 29 5 4.7 7.5 7.5 7.6 0. 2 SCSB0024 26,268 87 592.2 74.2 74.2 74.3 0. 2 SCSB0025 26,500 363,092 0.6 74.3 74.3 74.4 0. SCSB0026 26,780 25 275 2.5 75. 75. 75.2 0. SCSB0027 26,968 63 346 2.0 75.5 75.5 75.6 0. 2 SCSB0028 27,049 88 759 0.9 76.5 76.5 76.6 0. SCSB0029 27,376 40 7.0 76.6 76.6 76.7 0. SCSB0030 27,644 247 880 0.8 76.6 76.6 76.7 0. SCSB003 28,805 05 282 2.4 78.0 78.0 78. 0. 2 SCSB0032 29,76 43 37.8 79.4 79.4 79.5 0. SCSB0033 30,53 2 296 78 0.6 79.5 79.5 79.6 0. SCSB0034 30,376 2 204 643 0.6 79.6 79.6 79.7 0. In feet above confluence with Salt Creek 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA SPRING BROOK CREEK (SCSB)

FLOODING SOURCE CROSS SECTION Spring Brook Creek (SCSB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSB0035 30,80 70 85 2.0 720.4 720.4 720.5 0. SCSB0036 3,440 2 348 45 0.8 720.8 720.8 720.9 0. 2 SCSB0037 32,372 97 40 2.4 723.9 723.9 724.0 0. 2 SCSB0038 32,647 700 40 2.4 723.9 723.9 724.0 0. 2 SCSB0039 32,783 00 236.4 724.7 724.7 724.8 0. 2 SCSB0040 33,089 53 23 2.7 726.0 726.0 726. 0. SCSB004 33,322 33 36 2.4 729.3 729.3 729.4 0. SCSB0042 33,527 30 86 3.6 729.6 729.6 729.7 0. 2 SCSB0043 34,086 7 30.9 730.8 730.8 730.9 0. 2 SCSB0044 35,06 65 07 2.2 734.7 734.7 734.8 0. SCSB0045 35,455 22 58 4. 738.0 738.0 738. 0. SCSB0046 35,66 43 40.7 742.0 742.0 742. 0. SCSB0047 36,025 40 36.8 743.4 743.4 743.5 0. SCSB0048 36,226 64 203.2 744.5 744.5 744.6 0. SCSB0049 36,605 27 9 2.6 745. 745. 745.2 0. SCSB0050 36,86 63 77.4 747.2 747.2 747.3 0. SCSB005 37,365 49 89 2.4 748.4 748.4 748.5 0. In feet above confluence with Salt Creek 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA SPRING BROOK CREEK (SCSB)

FLOODING SOURCE CROSS SECTION Spring Brook Creek (SCSB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSB0052 38,075 22 46 4.6 753.3 753.3 753.4 0. SCSB0053 39,88 4 58 3.6 76.8 76.8 76.9 0. SCSB0054 39,30 24 64 3. 762. 762. 762.2 0. SCSB0055 39,634 27 58 3.5 764.3 764.3 764.4 0. SCSB0056 40,94 38 84 2.4 766.0 766.0 766. 0. SCSB0057 4,399 66 98 2.3 775.0 775.0 775. 0. SCSB0058 4,849 7 53 3.8 776.3 776.3 776.4 0. SCSB0059 42,346 2 459 2,3 0. 783.9 783.9 783.9 0.0 In feet above confluence with Salt Creek 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA SPRING BROOK CREEK (SCSB)

FLOODING SOURCE CROSS SECTION West Branch Tributary to Spring Brook Creek (SCSB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSB0060 688 2 45 86 3.2 72.3 72.3 72.4 0. SCSB006,708 2 80 53.8 726.5 726.5 726.6 0. 2 SCSB0062 2,225 25 03 2. 729.0 729.0 729. 0. SCSB0063 2,759 25 362 0.6 733.2 733.2 733.3 0. SCSB0064 3,233 25 48 4.5 736.3 736.3 736.4 0. SCSB0065 3,48 5 35 6. 740. 740. 740.2 0. SCSB0066 3,607 32 45.5 744.6 744.6 744.7 0. SCSB0067 3,829 3 70 3. 745.3 745.3 745.4 0. SCSB0068 4,30 33 52 9.9 749.5 749.5 749.6 0. In feet above confluence with Spring Brook Creek 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA W. BRANCH TRIBUTARY TO SPRING BROOK CREEK (SCSB)

FLOODING SOURCE CROSS SECTION Meacham Creek (SCSB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSB0069,880 76 84 0.4 703.7 703.7 703.8 0. SCSB0070 3,955 25 255.2 704.3 704.3 704.4 0. SCSB007 6,257 25 2 2.5 70.8 70.8 70.9 0. SCSB0072 7,043 30 367 0.8 73.9 73.9 74.0 0. SCSB0073 7,808 50 437 0.6 75.3 75.3 75.4 0. SCSB0074 9,0,376 6,25 0. 75.9 75.9 76.0 0. SCSB0075 9,724,257 6,43 0. 75.9 75.9 76.0 0. SCSB0076 0,74 293,97 0.2 75.9 75.9 76.0 0. In feet above confluence with Spring Brook Creek TABLE 5 DUPAGE COUNTY DATA MEACHAM CREEK (SCSB)

FLOODING SOURCE CROSS SECTION Salt Creek (SCSC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSC000 50,268 58,55 3.2 642.5 642.5 642.6 0. SCSC0002 54,76 699 2,856.7 644.6 644.6 644.8 0.2 SCSC026 55,284 2 28 362 9.6 645.5 645. 645. 0.0 SCSC027 55,844 206,407 2.5 646.9 646.9 646.9 0.0 SCSC028 58,044 243,564 2.2 647.3 647.3 647.3 0.0 SCSC029 60,244 956,749 4.8 647.9 647.9 647.9 0.0 SCSC030 62,204 50 977 3.5 650.3 650.3 650.4 0. SCSC03 65,044 397,343 3.5 653.5 653.5 653.6 0. SCSC033 65,294 407,470 3.3 653.8 653.8 653.9 0. SCSC034 68,24 780 3,60.8 654.6 654.7 654.8 0. SCSC035 70,454,42 4,254 2.0 655.0 655.0 655. 0. SCSC036 7,094,097 5,22.3 655.2 655.2 655.3 0. SCSC037 7,337 30,42 2.7 655.2 655.2 655.3 0. SCSC039 7,55 25 978 3.5 655.2 655.2 655.3 0. SCSC040 7,890 38 865 4. 655.4 655.4 655.5 0. SCSC04 72,530 99 864 3.6 656.0 656.0 656. 0. SCSC042 73,090 29,025 3. 656.3 656.3 656.5 0. SCSC043 73,50 06,030 3.0 656.5 656.5 656.7 0. In feet above mouth 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain 3 Width includes floodway of Spring Brook Creek TABLE 5 DUPAGE COUNTY DATA SALT CREEK (SCSC)

FLOODING SOURCE CROSS SECTION Salt Creek (SCSC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSC045 73,784 30,57 2.7 656.7 656.7 656.8 0. SCSC047 73,940 36,29 2.8 656.8 656.8 656.9 0. SCSC049 74,098 532 3,066.9 657.0 657.0 657. 0. SCSC050 74,208 723 3,65.5 657.0 657.0 657. 0. SCSC05 74,68 332,639 2.7 657. 657. 657.2 0. SCSC052 75,78 24,063 3.8 657.3 657.3 657.4 0. SCSC053 75,489 232,67 3.7 657.5 657.5 657.6 0. SCSC054 76,249 443 2,580 2. 657.9 657.9 658.0 0. SCSC055 76,659 393,790 2.0 658.0 658.0 658. 0. SCSC056 77,059 760,544 3.3 658.2 658.2 658.3 0. SCSC057 77,469 673 2,224 2.5 658.5 658.5 658.6 0. SCSC058 77,879 40 2,706 2.2 658.7 658.7 658.8 0. SCSC059 78,299 257,644 2. 658.8 658.8 658.9 0. SCSC060 79,254 70,87 3.2 659.4 659.4 659.5 0. SCSC06 79,844 36,23 3.2 659.9 659.9 660.0 0. SCSC062 80,34 46 877 4. 660.2 660.2 660.3 0. SCSC063 80,649 395,553 2.8 660.8 660.8 660.9 0. SCSC064 80,989 40 2,276 2.5 66. 66. 66.2 0. In feet above mouth 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain 3 Width includes floodway of Spring Brook Creek TABLE 5 DUPAGE COUNTY DATA SALT CREEK (SCSC)

FLOODING SOURCE CROSS SECTION Salt Creek (SCSC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSC065 8,029 85,676.8 66.2 66.2 66.3 0. SCSC007 8,250 73,298 2.4 662.0 66.5 66.6 0. SCSC008 82,935 30,438 2.2 662.5 662.5 662.5 0.0 SCSC009 83,56 50,96 2.6 662.5 662.5 662.5 0.0 SCSC0020 84,29 65,308 2.4 662.5 662.5 662.5 0.0 SCSC002 84,746 70,395 2.3 662.5 662.5 662.5 0.0 SCSC0022 85,504 250,479 2.6 662.7 662.7 662.7 0.0 SCSC0023 86,520 455,768 2.5 663.0 663.0 663. 0. SCSC0024 86,854 40,338 3.0 663.2 663.2 663.3 0. SCSC0025 87,370 445,246 3.0 663.7 663.7 663.8 0. SCSC0026 87,988 500 2,629.8 664. 664. 664.2 0. SCSC0027 9,964 30 2,242.6 665.9 665.9 666.0 0. SCSC0028 92,526 75,698 2.3 666.8 666.8 666.8 0.0 SCSC0029 93,878 70 2,346.6 667.5 667.5 667.6 0. SCSC0030 94,550 20 3,387.0 668.0 668.0 668. 0. SCSC003 96,32 2 300,75 2. 668.9 668.9 669.0 0. SCSC0032 97,866 20,935.8 67.5 67.5 67.6 0. SCSC0033 98,400 45 3,78 2. 672.0 672.0 672. 0. In feet above mouth 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain 3 Width includes floodway of Spring Brook Creek TABLE 5 DUPAGE COUNTY DATA SALT CREEK (SCSC)

FLOODING SOURCE CROSS SECTION Salt Creek (SCSC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSC0034 99,666 270 3,78 2. 672.3 672.3 672.4 0. SCSC0035 0,350 95 3,39.2 672.6 672.6 672.7 0. SCSC0036 02,50 387,537 2.3 673. 673. 673.2 0. SCSC0037 03,708 850 6,063 0.6 674.2 674.2 674.3 0. SCSC0038 06,683 860 3,568. 674.7 674.7 674.8 0. SCSC0039 07,935 903 5,067 0.8 674.8 674.8 674.9 0. SCSC0040,935 397 8,43 0.4 675. 675. 675.2 0. SCSC004 3,364 509 3,56. 675.3 675.3 675.4 0. SCSC0042 4,787 494 3,93.0 675.5 675.5 675.6 0. SCSC0043 7,307 450 5,450 0.7 675.7 675.7 675.8 0. SCSC0044 7,986 490 5,738 0.6 675.8 675.8 675.8 0.0 SCSC0045 23,076 900 4,526 0.8 676.7 676.7 676.7 0.0 SCSC0046 25,430 789 4,35 0.8 677.0 677.0 677. 0. SCSC0047 26,804 97 4,744 0.7 677.2 677.2 677.3 0. SCSC0048 30,335 429 2,685.3 678.2 678.2 678.3 0. SCSC0049 3,393 60 4,370 0.8 680.3 680.3 680.4 0. SCSC0050 32,433 67 4,503 0.8 680.3 680.3 680.4 0. SCSC005 32,732 67 4,503 0.8 680.3 680.3 680.4 0. In feet above mouth 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain 3 Width includes floodway of Spring Brook Creek TABLE 5 DUPAGE COUNTY DATA SALT CREEK (SCSC)

FLOODING SOURCE CROSS SECTION Salt Creek (SCSC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSC0052 34,624 608 4,62 0.8 680.6 680.6 680.7 0. SCSC0055 40,4 357,806.4 68.6 68.6 68.7 0. SCSC0056 40,896 300 2,909 0.9 68.9 68.9 68.9 0.0 SCSC0057 43,669 650 3,676 0.7 682.3 682.3 682.3 0.0 In feet above mouth 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain 3 Width includes floodway of Spring Brook Creek TABLE 5 DUPAGE COUNTY DATA SALT CREEK (SCSC)

FLOODING SOURCE CROSS SECTION Sugar Creek (SCSU) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSU000 2,659 592 2,482 0.4 665.4 665.4 665.5 0. SCSU0002 4,40 35,420 0.7 665.5 665.5 665.6 0. SCSC0003 4,547 240 944.0 665.7 665.7 665.8 0. SCSU0004 6,249 63 9 4.5 668.4 668.4 668.5 0. SCSU0005 6,964 25 97 8.8 668.9 668.9 669.0 0. SCSU0006 8,297 39 7.7 679.5 679.5 679.6 0. SCSU0007 9,400 52 66.3 687.3 687.3 687.4 0. SCSU0008 0,002 79 75 0.9 690.6 690.6 690.7 0. SCSU0009 0,369 00 454.5 690.7 690.7 690.8 0. SCSU000,240 25 32 2.2 69.0 69.0 69. 0. In feet above confluence with Salt Creek TABLE 5 DUPAGE COUNTY DATA SUGAR CREEK (SCSU)

FLOODING SOURCE CROSS SECTION Sugar Creek Tributary A (SCSU) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCSU00 57 49 57.9 688.2 2 687.9 688.0 0. SCSU002 564 5 62.8 688.4 688.4 688.5 0. SCSU003,677 06 20.4 704.4 704.4 704.5 0. SCSU004,9 40 06 2.7 704.5 704.5 704.6 0. In feet above confluence with Sugar Creek 2 Elevation computed without consideration of backwater effects from Sugar Creek TABLE 5 DUPAGE COUNTY DATA SUGAR CREEK TRIBUTARY A (SCSU)

FLOODING SOURCE CROSS SECTION Westwood Creek DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCWC000 225 3 330 889 0.7 675.7 675.7 675.8 0. SCWC0002,880 342,099 0.6 675.9 675.9 676.0 0. SCWC0003 2,720 49,47 0.6 676.2 676.2 676.3 0. SCWC0004 3,830 74 67 2.3 677.0 677.0 677. 0. 2 SCWC0005 4,726 40 459 0.9 679.5 680.5 680.6 0. SCWC0006 6,380 35 253.5 683.9 683.9 684.0 0. SCWC0007 7,80 25 268.4 684.8 684.8 684.9 0. SCWC0008 8,560 3 0 37 2.0 689.0 689.0 689. 0. SCWC0009 0,850 3 38 38.6 692. 692. 692.2 0. In feet above confluence with Salt Creek 2 Data shown are computed based on upstream cross section for conditions at approach to structure 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA WESTWOOD CREEK

FLOODING SOURCE CROSS SECTION South Fork of Westwood Creek (SCWC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SCWC000 450 65 87.3 685.4 685.4 685.4 0.0 SCWC00,850 545 4,332 0.0 693.3 693.3 693.3 0.0 SCWC002 3,000 770,897 0. 693.3 693.3 693.3 0.0 SCWC003 3,368 600 4,852 0.0 693.3 693.3 693.3 0.0 SCWC004 4,48 740 5,746 0. 693.3 693.3 693.3 0.0 SCWC005 5,540 220 754 0.4 693.4 693.4 693.4 0.0 In feet above confluence with Westwood Creek TABLE 5 DUPAGE COUNTY DATA SOUTH FORK OF WESTWOOD CREEK (SCWC)

FLOODING SOURCE CROSS SECTION Sawmill Creek (SWSW) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SWSW000 4,36 80 383 6.8 623.7 623.7 623.7 0.0 SWSW0002 8,240 60 787 3.3 652.0 652.0 652.0 0.0 SWSW0003,850 2 380,425.7 659.7 659.7 659.7 0.0 SWSW0004 4,352 50 78 3. 665.3 665.3 665.3 0.0 SWSW0005 6,06 70 578 2.3 669.2 669.2 669.2 0.0 SWSW0006 9,054 260 55 2.2 673.9 673.9 673.9 0.0 SWSW0007 2,603 70 439. 680.9 680.9 680.9 0.0 SWSW0008 25,020 99 299 2. 694.5 694.5 694.6 0. SWSW0009 26,90 266 25 2.6 709.5 709.5 709.6 0. SWSW000 28,44 40 04 4.5 72.5 72.5 72.6 0. In feet above confluence with Des Plaines River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA SAWMILL CREEK (SWSW)

FLOODING SOURCE CROSS SECTION West Branch Sawmill Creek (SWSW) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SWSW003 20,92 85 572 0.6 707.3 707.3 707.4 0. SWSW004 20,362 60 29.2 707.3 707.3 707.4 0. SWSW005 20,82 28 78 4.4 7.5 7.5 7.6 0. SWSW006 2,383 39 70 4.2 75. 75. 75.2 0. SWSW007 2,683 57 338 0.9 726.2 726.2 726.3 0. SWSW008 22,630 6 88.5 728.4 728.4 728.5 0. SWSW009 22,825 55 6.8 729.9 729.9 723.0 0. SWSW0020 23,035 88 226.3 73.8 73.8 73.9 0. SWSW002 23,35 5 265. 733.2 733.2 733.3 0. SWSW0022 23,693 66 85 3.3 734.2 734.2 734.3 0. SWSW0023 24,696 53 279 0.4 738.7 738.7 738.8 0. SWSW0024 25,6 402 2,3 0. 738.7 738.7 738.8 0. SWSW0025 25,945 29 24 3.4 742.0 742.0 742. 0. SWSW0026 26,679 5 6 5. 759.0 759.0 759. 0. In feet above confluence with Sawmill Creek TABLE 5 DUPAGE COUNTY DATA WEST BRANCH SAWMILL CREEK (SWSW)

FLOODING SOURCE CROSS SECTION East Branch Sawmill Creek (SWSW) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE SWSW0030 27,709 74 308.8 700.4 700.4 700.5 0. SWSW003 29,232 67 8 2.7 705.2 705.2 705.3 0. SWSW0032 30,478 272 292.4 70.6 70.6 70.7 0. SWSW0033 30,78 47 263.3 74.8 74.8 74.9 0. SWSW0034 3,906 7 274.2 75.2 75.2 75.3 0. 2 SWSW0035 32,376 9 7 3.3 77.4 77.3 77.4 0. SWSW0036 33,386 59 70 2.4 720.0 720.0 720. 0. SWSW0037 34,493 23 55 0.3 724. 724. 724.2 0. SWSW0038 36,496 304 543 0.2 724. 724. 724.2 0. SWSW0039 36,746 386,73 0. 724. 724. 724.2 0. In feet above confluence with Sawmill Creek 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DATA EAST BRANCH SAWMILL CREEK (SWSW)

FLOODING SOURCE CROSS SECTION Cress Creek (WBCC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBCC000 307 505 98 3.9 680.2 2 673.9 673.9 0.0 WBCC0002,94 52 0 3.8 680.2 2 676.5 676.5 0.0 WBCC0003 2,059 37 90 4.3 680.2 2 678.0 678.0 0.0 WBCC0004 3,53 35 94 4. 680.4 680.4 680.4 0.0 WBCC0005 4,05 47 3.5 688.2 688.2 688.2 0.0 WBCC0006 5,200 23 5 7.6 690.2 690.2 690.2 0.0 WBCC0007 5,560 47 39 2.8 692.6 692.6 692.6 0.0 WBCC0008 6,065 32 98 3.9 693.0 693.0 693.0 0.0 In feet above confluence with West Branch DuPage River 2 Elevations computed without consideration of backwater effects from West Branch DuPage River TABLE 5 DUPAGE COUNTY DATA CRESS CREEK (WBCC)

FLOODING SOURCE CROSS SECTION Ferry Creek (WBFE) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBFE0006 3,538 50 56.2 69.2 690.6 690.6 0.0 WBFE0007 3,854 50 423.0 69.2 690.6 690.6 0.0 WBFE0008 4,03 25 426.0 69.4 69.4 69.4 0.0 WBFE0009 5,227 227 32.4 692.2 692.2 692.3 0. WBFE000 6,230 253 300.5 693.2 693.2 693.3 0. WBFE00 7,840 57 263.7 695. 695. 695.2 0. WBFE002 8,395 200 2.2 696.9 696.9 696.9 0.0 WBFE003 8,72 62 6 3.8 697.2 697.2 697.3 0. WBFE004 9,45 25 54 2.9 699.5 699.5 699.6 0. WBFE005 0,454 22 77 2.5 702.0 702.0 702. 0. WBFE006,4 200 505 0.5 704. 704. 704. 0.0 WBFE007 2,672 90 5.8 704.2 704.2 704.2 0.0 WBFE008 3,834 76 09 2.4 705.9 705.9 706.0 0. WBFE009 4,44 84 34 2.0 707. 707. 707.2 0. WBFE0020 5,205 30 334 0.8 7.5 7.5 7.5 0.0 WBFE002 5,630 49 33 2.0 7.6 7.6 7.6 0.0 WBFE0022 5,780 59 47.8 7.8 7.8 7.8 0.0 WBFE0023 6,000 6 46 5.8 72.7 72.7 72.7 0.0 In feet above confluence with West Branch DuPage River TABLE 5 DUPAGE COUNTY DATA FERRY CREEK (WBFE)

FLOODING SOURCE CROSS SECTION Ferry Creek (WBFE) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBFE0024 7,475 260,29 0.2 76.2 76.2 76.2 0.0 WBFE0025 8,955 246 539 0.3 76.2 76.2 76.2 0.0 In feet above confluence with West Branch DuPage River TABLE 5 DUPAGE COUNTY DATA FERRY CREEK (WBFE)

FLOODING SOURCE CROSS SECTION Ferry Creek Tributary No. (WBFE) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBFE000,35 6 06 2.8 69.2 2 687.5 687.5 0.0 WBFE0002,339 32 90 3.3 69.2 2 689. 689. 0.0 WBFE0003 3,644 82 293.0 697.4 697.4 697.5 0. WBFE0004 4,800 26 94 2.6 699.8 699.8 699.9 0. In feet above confluence with Ferry Creek 2 Elevations computed without consideration of backwater effects from Ferry Creek TABLE 5 DUPAGE COUNTY DATA FERRY CREEK TRIBUTARY NO. (WBFE)

FLOODING SOURCE CROSS SECTION Unnamed Creek (South of Foxcroft Road) (WBFX) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBFX000 802 79 22.3 646.8 646.8 646.9 0. WBFX0002,298 307 82 0.4 65.0 65.0 65.0 0.0 WBFX0003,890 404 535 0.5 65. 65. 65. 0.0 WBFX0004 2,929 93 200 2.0 654. 654. 654.2 0. WBFX0005 3,80 29 327 0.6 654.2 654.2 654.2 0.0 In feet above county boundary TABLE 5 DUPAGE COUNTY DATA UNNAMED CREEK (SOUTH OF FOXCROFT ROAD) (WBFX)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE Unnamed Creek (South of 87th Street) (WBFX) WBFX00 6,09 26 256 6. 655. 655. 655. 0.0 WBFX002 6,44 2 70 6.5 66.3 66.5 66.5 0.0 In feet above mouth TABLE 5 DUPAGE COUNTY DATA UNNAMED CREEK (SOUTH OF 87TH STREET) (WBFX)

FLOODING SOURCE CROSS SECTION Klein Creek (WBKC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBKC000,956 79 28 4.2 72.5 2 720.7 720.7 0.0 WBKC0002 4,952 490 94.0 728.8 728.8 728.8 0.0 WBKC0003 6,795 59,524 0.6 735. 735. 735. 0.0 WBKC0004 8,37 2 389 2.3 739.5 739.5 739.5 0.0 WBKC0005 8,849 3 303 3.0 740.3 740.3 740.3 0.0 WBKC0006 9,34 62 79. 743. 743. 743.2 0. WBKC0007 0,952 40 257 3.5 743.9 743.9 744.0 0. WBKC0008 2,52 60,757 0.5 746.0 746.0 746.0 0.0 WBKC0009 3,880 250 338 2.7 746.0 746.0 746.0 0.0 WBKC000 5,68 04 254 2.6 747.2 747.2 747.2 0.0 WBKC00 7,948 78 262 2.4 748.4 748.4 748.4 0.0 WBKC002 8,466 575 2,482 0.2 748.6 748.6 748.6 0.0 WBKC003 20,84 294 5,222 0. 75.8 75.8 75.8 0.0 WBKC004 2,590 525 7,852 0. 75.8 75.8 75.8 0.0 WBKC005 22,804 294 4,74 0. 752.9 752.9 753.0 0. WBKC006 24,228 242 3,274 0.2 754.8 754.8 754.9 0. WBKC007 25,727 679,442 0.4 755.6 755.6 755.7 0. WBKC008 27,954 288 908 0.4 76.5 76.5 76.5 0.0 In feet above confluence with West Branch DuPage River 2 Elevation computed without consideration of backwater effect from West Branch DuPage River 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA KLEIN CREEK (WBKC)

FLOODING SOURCE CROSS SECTION Klein Creek (WBKC) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBKC009 30,92 65 60 5.4 762.2 762.2 762.2 0.0 WBKC0020 33,209 287 484 0.7 768.5 768.5 768.5 0.0 In feet above confluence with West Branch DuPage River 2 Elevation computed without consideration of backwater effect from West Branch DuPage River 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA KLEIN CREEK (WBKC)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE Klein Creek Tributary N0 2 (WBKC) WBKC0024 3 32 66 5.4 747.3 2 744.8 744.9 0. WBKC0025 250 36 8 4.4 747.3 2 745.4 745.4 WBKC0026,63 36 95 3.7 748.3 748.3 748.3 WBKC0027,365 94 44 2.5 748.8 748.8 748.8 WBKC0028,770 33 75 4.7 749.6 749.6 749.7 0. WBKC0029 2,33 35 73 4.8 75.6 75.6 75.6 WBKC0030 2,30 46 33 2.7 753. 753. 753. In feet above confluence with East Branch DuPage River 2 Elevations without considering backwater effect from Klein Creek TABLE 5 DUPAGE COUNTY DATA Klein Creek Tributary N0 2 (WBKC)

FLOODING SOURCE CROSS SECTION Kress Creek (WBKR) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBKR000 882 39 464 2.5 705.5 2 703.2 703.3 0. WBKR0002,22 50 572 2.0 705.5 2 704.0 704. 0. WBKR0003 3,080 65 23 5. 709.5 709.5 709.5 0.0 WBKR0004 5,63 95 293 4.0 75.6 75.6 75.7 0. WBKR0005 5,782 259,32 0.9 720.2 720.2 720.3 0. WBKR0006 6,805 250,289 0.9 72.3 72.3 72.4 0. WBKR0007 7,562 78 2,334 0.5 722. 722. 722.2 0. WBKR0008 8,006 3 45 3,28 0.4 722. 722. 722.2 0. WBKR0009 0,324 3 220 289.7 722.2 722.2 722.3 0. WBKR000,6 3 330,508 0.7 727.2 727.2 727.2 0.0 WBKR00 3,563 5 27 3.7 727.4 727.4 727.4 0.0 WBKR002 6,205 290,076 0.9 734.3 734.3 734.3 0.0 WBKR003 7,053 52,558 0.6 735.7 735.7 735.7 0.0 WBKR004 8,982 20 557.6 737.9 737.9 737.9 0.0 WBKR005 20,423 25 400 2.2 738.6 738.6 738.7 0. WBKR006 22,75 33 09 2.4 738.7 738.7 738.8 0. WBKR007 23,240 2 64 4. 738.7 738.7 738.7 0.0 WBKR008 23,656 30 89.6 740. 740. 740. 0.0 In feet above confluence with West Branch DuPage River 2 Elevations computed without consideration of backwater effects from West Branch DuPage River 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA KRESS CREEK (WBKR)

FLOODING SOURCE CROSS SECTION Kress Creek (WBKR) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBKR009 25,234 28 60.6 740.7 740.7 740.8 0. WBKR0020 25,526 3 58 50 2.2 744.4 744.4 744.4 0.0 WBKR002 26,35 3 68 233.2 744.9 744.9 745.0 0. WBKR0022 26,579 3 66 235.0 745.2 745.2 745.3 0. WBKR0023 27,985 49 33.5 745.6 745.6 745.7 0. WBKR0024 28,58 8 273 0.7 746.3 746.3 746.4 0. WBKR0025 28,722 3 35.4 746.3 746.3 746.4 0. WBKR0026 28,897 35 22.0 748.4 748.4 748.5 0. WBKR0027 30,320 39 95 0.7 748.6 748.6 748.7 0. WBKR0028 30,482 40 246 0.6 749.8 749.8 749.9 0. WBKR0029 32,036 36 93 0.8 749.8 749.8 750.0 0. WBKR0030 32,284 40 64 0.9 749.8 749.8 749.8 0.0 WBKR003 34,078 68 40 0.7 750.0 750.0 750.0 0.0 WBKR0032 34,85 38 6.7 750.8 750.8 750.8 0.0 WBKR0033 36,853 24 74 0.6 75.7 75.7 75.7 0.0 WBKR0034 37,424 20 52 0.9 75.7 75.7 75.7 0.0 WBKR0035 4,489 79 529 0. 755.7 755.7 755.8 0. WBKR0036 4,620 222 96 0. 755.7 755.7 755.8 0. In feet above confluence with West Branch DuPage River 2 Elevations computed without consideration of backwater effects from West Branch DuPage River 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA KRESS CREEK (WBKR)

FLOODING SOURCE CROSS SECTION Kress Creek (WBKR) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE 3 WBKR0037 42,236 6 507 0. 755.7 755.7 755.8 0. In feet above confluence with West Branch DuPage River 2 Elevations computed without consideration of backwater effects from West Branch DuPage River 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA KRESS CREEK (WBKR)

FLOODING SOURCE CROSS SECTION Unnamed Tributary to Kress Creek (WBKR) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBKR0038,303 55 693 0.2 732.6 732.6 732.6 0.0 WBKR0039 2,06 28 56 2.8 732.6 732.6 732.6 0.0 WBKR0040 2,426 200 32 0.5 734.7 734.7 734.7 0.0 WBKR004 2,649 62 334 0.5 736.7 736.7 736.7 0.0 WBKR0042 3,876 30 37 4. 74.7 74.7 74.7 0.0 WBKR0043 4,05 77 66 0.9 744.3 744.3 744.3 0.0 WBKR0044 4,850 24 47 2.6 744.6 744.6 744.6 0.0 WBKR0045 5,27 99 22 0.8 749.0 749.0 749.0 0.0 WBKR0046 5,728 67 99.3 749. 749. 749. 0.0 WBKR0047 6,8 3 80.6 749.2 749.2 749.2 0.0 WBKR0048 6,544 785 89 0.7 749.2 749.2 749.2 0.0 WBKR0049 7,088 5 5 7.9 750. 750. 750. 0.0 WBKR0050 7,560 30 5.4 75.9 75.9 75.9 0.0 WBKR005 8,00 25 83 0.7 752.5 752.5 752.5 0.0 WBKR0052 8,59 45 93 0.9 752.9 752.9 752.9 0.0 WBKR0053 9,24 300 985 0. 757.0 757.0 757.0 0.0 WBKR0054,762 63 579 0. 757.0 757.0 757.0 0.0 In feet above confluence with Kress Creek TABLE 5 DUPAGE COUNTY DATA UNNAMED TRIBUTARY TO KRESS CREEK (WBKR)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE Unnamed Tributary to Kress Creek (WBKR) WBKR0055,950 35 22 0.7 758.6 758.6 758.6 0.0 In feet above confluence with Kress Creek TABLE 5 DUPAGE COUNTY DATA UNNAMED TRIBUTARY TO KRESS CREEK (WBKR)

FLOODING SOURCE CROSS SECTION Spring Brook No. (WBSP) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBSP000 454 90 376 2.2 697.7 2 693.8 693.9 0. WBSP0002 2,88 226 765.0 700. 700. 700.2 0. WBSP0003 4,685 84 335 2.4 707.3 707.3 707.3 0.0 WBSP0004 8,264 22 570.3 7.2 7.2 7.3 0. WBSP0005,209 248 482.5 74. 74. 74.2 0. WBSP0006 2,52 20 363 2.0 76.8 76.8 76.9 0. WBSP0007 4,528 94 597. 720. 720. 720.2 0. WBSP0008 5,242 305 897 0.8 720.5 720.5 720.6 0. WBSP0009 5,736 96 496. 722.4 722.4 722.5 0. 3 WBSP000 6,944 205,539 0.4 723.0 722.9 723.0 0. WBSP00 7,974 292,466 0.4 723.5 723.5 723.6 0. WBSP002 8,2 432,205 0.5 723.6 723.6 723.7 0. WBSP003 8,506 466,479 0.4 723.6 723.6 723.7 0. WBSP004 9,445 2 2,237 0.2 723.7 723.7 723.8 0. WBSP005 20,8 8 777 0.7 723.7 723.7 723.8 0. WBSP006 20,724 56,27 0.4 723.8 723.8 723.9 0. WBSP007 2,606 64 225 2.4 723.9 723.9 724.0 0. In feet above confluence with West Branch DuPage River 2 Elevations computed without consideration of backwater effects from West Branch DuPage River 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA SPRING BROOK NO. (WBSP)

FLOODING SOURCE CROSS SECTION Spring Brook No. (WBSP) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBSP008 22,037 78 520. 724.2 724.2 724.3 0. WBSP009 23,084 200 296.7 725.3 725.3 725.4 0. WBSP0020 24,80 00 228 2. 725.9 725.9 726.0 0. WBSP002 25,600 3 40 3.5 727.4 727.4 727.4 0.0 WBSP0022 25,87 40 77 2.8 727.7 727.7 727.8 0. WBSP0023 30,54 47 30.4 73. 73. 73.2 0. In feet above confluence with West Branch DuPage River 2 Elevations computed without consideration of backwater effects from West Branch DuPage River 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA SPRING BROOK NO. (WBSP)

FLOODING SOURCE CROSS SECTION West Branch DuPage River (WBWB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBWB000 2,038 40 2,435 2.3 647. 647. 647.2 0. WBWB0002 4,002 402,428 3.9 650. 650. 650.2 0. WBWB0003 6,777 27,543 3.6 654. 654. 654.2 0. 2 WBWB0004 9,660 205,683 3.3 657.3 657.3 657.4 0. WBWB0005 20,580 54,200 4.7 658.5 658.5 658.6 0. WBWB0006 22,06 302 2,63 2.6 66.5 66.5 66.6 0. WBWB0007 24,64 400,475 3.8 663. 663. 663.2 0. WBWB0008 26,343 270,692 3.3 664.2 664.2 664.3 0. WBWB0009 29,06 450,059 4.2 669.6 669.6 669.6 0.0 WBWB000 29,82 66 3,52.4 670.3 670.3 670.3 0.0 WBWB00 30,953 66,53 3.8 670.9 670.9 67.0 0. WBWB002 3,409 9 876 5.0 67.9 67.9 672.0 0. WBWB003 32,344 22,92 3.7 673.4 673.4 673.5 0. WBWB004 33,5 80 646 6.8 674.9 674.9 674.9 0.0 WBWB005 34,459 346 2,074 2. 676.7 676.7 676.8 0. WBWB006 36,869 330,636 2.7 678.0 678.0 678. 0. WBWB007 39,59 550,585 2.8 680. 680. 680.2 0. In feet above confluence with DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA WEST BRANCH DUPAGE RIVER (WBWB)

FLOODING SOURCE CROSS SECTION West Branch DuPage River (WBWB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBWB008 4,59 400,22 3.2 68.5 68.5 68.6 0. WBWB009 42,423 90,238 3.2 682. 682. 682.2 0. WBWB0020 46,993 720 7,287 0.7 69. 69. 69.2 0. WBWB002 5,222 2,040,87 0.4 69.5 69.5 69.5 0.0 WBWB0022 52,928 244,830 2.5 69.5 69.5 69.6 0. 2 WBWB0023 53,337 20,530 3.0 69.7 69.7 69.8 0. WBWB0024 55,739 290,779 2.6 692.8 692.8 692.9 0. WBWB0025 57,580 5,03 4.3 693.8 693.8 693.9 0. WBWB0026 57,804 89,229 3.6 694.6 694.6 694.7 0. WBWB0027 58,983 300 2,82 2.0 695.3 695.3 695.4 0. WBWB0028 59,484 240,369 3.2 695.6 695.6 695.7 0. WBWB0029 6,496 392,765 2.5 696.7 696.7 696.8 0. WBWB0030 62,029 433 2,23 2.0 697.5 697.5 697.6 0. WBWB003 63,679 444 2,383.7 697.9 697.9 698.0 0. WBWB0032 63,822 462 2,677.5 698.5 698.5 698.6 0. WBWB0033 65,356 325 987 4.2 698.8 698.8 698.9 0. WBWB0034 65,59 288 990 4. 699. 699. 699.2 0. In feet above confluence with DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA WEST BRANCH DUPAGE RIVER (WBWB)

FLOODING SOURCE CROSS SECTION West Branch DuPage River (WBWB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBWB0035 69,409 294,600 2.6 702.2 702.2 702.3 0. WBWB0036 7,400 226,352 2.8 703.0 703.0 703. 0. WBWB0037 74,58 223,432 2.7 705.0 705.0 705. 0. WBWB0038 76,742 499 2,249.3 706. 706. 706.2 0. WBWB0039 78,384 92,269 2.3 706.5 706.5 706.6 0. WBWB0040 79,605 95,2 2.3 707.2 707.2 707.3 0. WBWB004 79,776 98,57 2.3 707.5 707.5 707.6 0. WBWB0042 8,74 265,407.9 708.2 708.2 708.3 0. WBWB0043 88,642 339,438.9 70.9 70.9 7.0 0. WBWB0044 9,720 330,804.5 72.2 72.2 72.3 0. WBWB0045 93,630 07 698 3.4 73. 73. 73.2 0. WBWB0046 93,877 07 729 3.3 73.3 73.3 73.4 0. WBWB0047 94,400 07 783 3. 73.8 73.8 73.9 0. WBWB0048 94,739 200,59 2. 74.7 74.7 74.8 0. WBWB0049 95,05 540 2,225. 74.9 74.9 75.0 0. WBWB0050 00,03 225,063 2.3 76.7 76.7 76.8 0. WBWB005 0,779 709 3,079 0.8 720.5 720.5 720.6 0. In feet above confluence with DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA WEST BRANCH DUPAGE RIVER (WBWB)

FLOODING SOURCE CROSS SECTION West Branch DuPage River (WBWB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBWB0052 02,037 760 3,90 0.6 72.5 72.5 72.6 0. WBWB0053 04,58 323,360.4 72.6 72.6 72.7 0. WBWB0054 08,649 647,792. 722.5 722.5 722.6 0. WBWB0055,349 949 2,3 0.8 724.3 724.3 724.4 0. WBWB0056 2,67 29,00.9 726.8 726.8 726.9 0. WBWB0057 5,066 54 650 2.4 729.4 729.4 729.4 0.0 WBWB0058 6,204 48,99 0.8 730. 730. 730.2 0. WBWB0059 8,09 230,39.4 730.6 730.6 730.7 0. WBWB0060 9,08 206 736 2. 73.5 73.5 73.6 0. WBWB006 20,92 243 944.6 732.9 732.9 733.0 0. WBWB0062 22,229 54,99 0.8 733.4 733.4 733.5 0. WBWB0063 25,483 446 939.6 734.3 734.3 734.4 0. WBWB0064 28,59 358 775.8 737.8 737.8 737.9 0. WBWB0065 29,669 582,064.3 738.8 738.8 738.9 0. WBWB0066 3,994 3 376 3.8 742.0 742.0 742. 0. WBWB0067 33,92 366,432.0 746.4 746.4 746.5 0. WBWB0068 36,354 446,200.2 747.5 747.5 747.6 0. In feet above confluence with DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA WEST BRANCH DUPAGE RIVER (WBWB)

FLOODING SOURCE CROSS SECTION West Branch DuPage River (WBWB) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBWB0069 38,028 369,737.3 748.9 748.9 749.0 0. WBWB0070 4,759 82 597 2.4 752.9 752.9 753.0 0. WBWB007 46,706 340,063.3 758.4 758.4 758.5 0. WBWB0072 50,725 300 694.7 764.6 764.6 764.7 0. WBWB0073 53,225 270 928.3 767.6 767.6 767.7 0. WBWB0074 55,624 80 766.5 768.5 768.5 768.6 0. WBWB0075 58,003 00 32 3.7 77.5 77.5 77.6 0. WBWB0076 59,859 294 593 2.0 774.4 774.4 774.5 0. WBWB0077 6,936 28 372 2.5 775.9 775.9 776.0 0. In feet above confluence with DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA WEST BRANCH DUPAGE RIVER (WBWB)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE West Branch Tributary No. (WBW) WBW000 6,000 300,859 0. 768.7 2 768.7 768.8 0. WBW0002 9,00 228 70 0.3 770.8 770.9 770.9 0. WBW0003 0,390 3 93 349 0.5 77.7 77.8 77.8 0. In feet above confluence with West Branch DuPage River 2 Elevation computed without consideration of backwater effects from West Branch DuPage River 3 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA WEST BRANCH TRIBUTARY NO. (WBW)

FLOODING SOURCE CROSS SECTION West Branch Tributary No. 2 (Country Creek) (WBW2) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBW2000 2,783 32 63 6.8 754.4 754.4 754.5 0. WBW20002 6,570 283 33.2 77.3 77.3 77.4 0. WBW20003 7,00 263,295 0.3 77.4 77.4 77.5 0. WBW20004 7,775 04 258.7 773.4 773.4 773.4 0.0 WBW20005,20 84 37 0.9 78.8 78.8 78.8 0.0 In feet above confluence with West Branch DuPage River TABLE 5 DUPAGE COUNTY DATA WEST BRANCH TRIBUTARY NO. 2 (COUNTRY CREEK) (WBW2)

FLOODING SOURCE CROSS SECTION West Branch Tributary No. 3 (WBW3) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBW3000,858 224 382. 726. 2 725.9 726.0 0. WBW30002 3,086 75 60 0.7 732.9 732.9 733.0 0. WBW30003 3,560 0 785 0.6 734.8 734.8 734.8 0.0 WBW30004 4,922 400 2,04 0.2 734.8 734.8 734.8 0.0 WBW30005 6,464 57 26 3.7 738.2 738.2 738.2 0.0 WBW30006 7,684 7 70 3.8 750.0 750.0 750. 0. WBW30007 8,080 93 377 3.7 750.9 750.9 75.0 0. In feet above confluence with West Branch DuPage River 2 Elevation computed without considering backwater effects from West Branch DuPage River TABLE 5 DUPAGE COUNTY DATA WEST BRANCH TRIBUTARY NO. 3 (WBW3)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE West Branch Tributary No. 6 (WBW6) WBW6000,294 23 6 4.6 667.0 667.0 667. 0. WBW60002 2,733 2 266 335 0.8 684.8 684.8 684.9 0. In feet above confluence with West Branch DuPage River 2 Actual floodway width cannot be shown on FIRM due to redelineation of floodplain TABLE 5 DUPAGE COUNTY DATA WEST BRANCH TRIBUTARY NO. 6 (WBW6)

FLOODING SOURCE CROSS SECTION DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE West Branch Tributary No. 7 (WBW7) WBW7000,793 3 3 3 674.5 3 3 3 2 WBW70002 3,36 3 3 3 683.3 3 3 3 In feet above confluence with West Branch DuPage River 2 Cross-section is shown on FIRM; not on profile 3 Data not available TABLE DUPAGE COUNTY DATA WEST BRANCH TRIBUTARY NO. 7 (WBW7)

FLOODING SOURCE CROSS SECTION Winfield Creek (WBWF) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBWF000 6 273 86 0.9 72.4 2 72.4 72.5 0. WBWF0002 533 89 480.6 72.4 2 72.4 72.5 0. WBWF0003 925 22 507.5 72.4 2 72.4 72.5 0. WBWF0004,600 279 493.5 73.6 73.6 73.7 0. WBWF0005,684 306 76.0 73.8 73.8 73.9 0. WBWF0006 2,006 307 754.0 75.4 75.4 75.5 0. WBWF0007 2,20 288 723.0 75.5 75.5 75.6 0. WBWF0008 2,44 263 675. 77.2 77.2 77.3 0. WBWF0009 2,900 265,26 0.6 77.3 77.3 77.4 0. WBWF000 3,748 52 2,473 0.3 77.3 77.3 77.4 0. WBWF00 4,530 607 2,69 0.3 77.3 77.3 77.4 0. WBWF002 5,400 83 599.3 77.4 77.4 77.5 0. WBWF003 6,362 363 876 0.8 77.9 77.9 78.0 0. WBWF004 7,230 700,958 0.4 78. 78. 78.2 0. WBWF005 7,603 74 384.8 78.3 78.3 78.4 0. WBWF006 8,3 257 623. 79.5 79.5 79.6 0. WBWF007 8,730 275 489.4 720.3 720.3 720.4 0. WBWF008 9,000 685,932 0.3 722.2 722.2 722.3 0. In feet above West Branch DuPage River 2 Elevations include backwater effects from the West Branch DuPage River TABLE 5 DUPAGE COUNTY DATA WINFIELD CREEK (WBWF)

FLOODING SOURCE CROSS SECTION Winfield Creek (WBWF) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBWF009,9 40,07 0.7 723.5 723.5 723.6 0. WBWF0020 2,500 47 584. 724.4 724.4 724.5 0. WBWF002 3,440 03 87 3.6 724.6 724.6 724.7 0. WBWF0022 4,487 3 40 3.6 726.5 726.5 726.5 0.0 WBWF0023 5,622 73 497.0 727.5 727.5 727.6 0. WBWF0024 6,890 00 365 0.9 728. 728. 728.2 0. WBWF0025 7,296 34 82.8 728.4 728.4 728.4 0.0 WBWF0026 7,732 280 628 0.5 728.5 728.5 728.5 0.0 WBWF0027 8,930 26 234.4 728.9 728.9 728.9 0.0 WBWF0028 9,805 40 96.6 73.0 73.0 73. 0. WBWF0029 20,00 43 229.4 73. 73. 73.2 0. WBWF0030 20,80 20 47 0.8 73.4 73.4 73.5 0. WBWF003 2,650,70 74 4.3 732.2 732.2 732.3 0. WBWF0032 24,02 57 3,325 0. 732.2 732.2 732.3 0. WBWF0033 24,389 494 2,365 0. 732.2 732.2 732.3 0. WBWF0034 24,975 669 2,590 0.2 732.2 732.2 732.3 0. WBWF0035 25,783 655 2,248 0.2 732.2 732.2 732.3 0. WBWF0036 27,5 320 420.2 732.5 732.5 732.6 0. In feet above West Branch DuPage River 2 Elevations include backwater effects from the West Branch DuPage River TABLE 5 DUPAGE COUNTY DATA WINFIELD CREEK (WBWF)

FLOODING SOURCE CROSS SECTION Winfield Creek (WBWF) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBWF0037 27,493 33 4 5.2 732.6 732.6 732.7 0. WBWF0038 28,05 2 256 2. 733.9 733.9 734.0 0. WBWF0039 28,749 77 306.7 738.7 738.7 738.8 0. WBWF0040 30,33 57 5 3.5 744. 744. 744. 0.0 WBWF004 30,793 3 326.6 744.7 744.7 744.7 0.0 WBWF0042 30,989 455,029 0.5 747.0 747.0 747.0 0.0 WBWF0043 32,646 75 557.0 747. 747. 747. 0. WBWF0044 33,272 330 2,249 0.3 747. 747. 747. 0.0 WBWF0045 33,655 60 367.4 747. 747. 747. 0.0 WBWF0046 35,45 38 73 3.6 748.0 748.0 748.0 0.0 In feet above West Branch DuPage River 2 Elevations include backwater effects from the West Branch DuPage River TABLE 5 DUPAGE COUNTY DATA WINFIELD CREEK (WBWF)

FLOODING SOURCE CROSS SECTION Winding Creek (WBWG) DISTANCE WIDTH (FEET) SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) BASE FLOOD WATER SURFACE ELEVATION (FEET NAVD) REGULATORY WITHOUT WITH INCREASE WBWG000 3,554 425 2,83 0. 678.0 678.0 678.0 0.0 WBWG0002 4,452 06 204 0.6 68.3 68.3 68.3 0.0 WBWG0003 5,525 22 437 0.3 68.3 68.3 68.3 0.0 WBWG0004 5,935 44 8.0 68.4 68.4 68.4 0.0 In feet above confluence with West Branch DuPage River TABLE 5 DUPAGE COUNTY DATA WINDING CREEK (WBWG)

CROSS SECTION FLOODING SOURCE DISTANCE WIDTH (FEET) RIVER CHANNEL SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) STREAM-BED ELEVATION (FT. NGVD) BASE FLOOD WATER SURFACE ELEVATIONS (FEET NGVD) East Branch Tributary No. (EBE) EBE000 742 * * * 70.5 703.8 EBE0002 4620 * * * 74.0 78.5 EBE0003 4726 * * * 74.4 78.8 In feet above confluence with East Branch DuPage River *Data not available TABLE 6 00-YEAR FLOOD DATA EAST BRANCH TRIBUTARY NO. (EBE)

CROSS SECTION East Branch FLOODING SOURCE DISTANCE WIDTH (FEET) RIVER CHANNEL SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) STREAM-BED ELEVATION (FT. NGVD) BASE FLOOD WATER SURFACE ELEVATIONS (FEET NGVD) Tributary No. 7 (EBE7) EBE7000,690 * * * 660.6 668.3 EBE70002 4,835 * * * 682.0 687.2 EBE70003 5,062 * * * 682.7 689.7 EBE70004 5,235 * * * 690.5 694.5 EBE70005 5,345 * * * 690.8 697.7 EBE70006 6,635 * * * 708.5 70.8 EBE70007 7,664 * * * 79.5 726.3 In feet above confluence with East Branch DuPage River TABLE 6 00-YEAR FLOOD DATA EAST BRANCH TRIBUTARY NO. 7 (EBE7)

CROSS SECTION Sawmill Creek Tributary No. (SWSW) FLOODING SOURCE DISTANCE WIDTH (FEET) RIVER CHANNEL SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) STREAM-BED ELEVATION (FT. NGVD) BASE FLOOD WATER SURFACE ELEVATIONS (FEET NGVD) SWSW0027 9,298 * * * 673.6 679. SWSW0028 2,965 * * * 682.7 689.7 SWSW0029 23,57 * * * 688.0 694.6 In feet above confluence with Sawmill Creek * Data not available TABLE 6 00-YEAR FLOOD DATA (SWSW) SAWMILL CREEK TRIBUTARY NO.

CROSS SECTION Wards Creek (SWSW) FLOODING SOURCE DISTANCE WIDTH (FEET) RIVER CHANNEL SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) STREAM-BED ELEVATION (FT. NGVD) BASE FLOOD WATER SURFACE ELEVATIONS (FEET NGVD) SWSW00 5,58 * * * 665.8 670.4 SWSW002 9,298 * * * 683.9 688.8 In feet above confluence with Sawmill Creek * Data not available TABLE 6 00-YEAR FLOOD DATA WARDS CREEK (SWSW)

CROSS SECTION Klein Creek Tributary No. (WBKC) FLOODING SOURCE DISTANCE WIDTH (FEET) RIVER CHANNEL SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) STREAM-BED ELEVATION (FT. NGVD) BASE FLOOD WATER SURFACE ELEVATIONS (FEET NGVD) WBKC002,600 * * * 734.5 738.4 WBKC0022 4,490 * * * 749.8 754.0 WBKC0023 6,488 * * * 757.0 762.3 In feet above confluence with Klein Creek * Data not available TABLE 6 00-YEAR FLOOD DATA KLEIN CREEK TRIBUTARY NO. (WBKC)

CROSS SECTION Klein Creek Tributary No. 3 (WBKC) FLOODING SOURCE DISTANCE WIDTH (FEET) RIVER CHANNEL SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) STREAM-BED ELEVATION (FT. NGVD) BASE FLOOD WATER SURFACE ELEVATIONS (FEET NGVD) WBKC003,280 * * * 754.5 757.9 WBKC0032 2,264 * * * 756.0 758.3 WBKC0033 3,507 * * * 760.8 767.2 In feet above confluence with Klein Creek * Data not available TABLE 6 00-YEAR FLOOD DATA KLEIN CREEK TRIBUTARY NO. 3 (WBKC)

CROSS SECTION West Branch Tributary No. 5 (WBW5) FLOODING SOURCE DISTANCE WIDTH (FEET) RIVER CHANNEL SECTION AREA (SQUARE FEET) MEAN VELOCITY (FEET PER SECOND) STREAM-BED ELEVATION (FT. NGVD) BASE FLOOD WATER SURFACE ELEVATIONS (FEET NGVD) WBW5000 62 * * * 707.0 709.8 WBW50002,28 * * * 72.0 77.4 WBW50003,748 * * * 720.3 722.7 In feet above confluence with West Branch DuPage River * Data not available TABLE 6 00-YEAR FLOOD DATA WEST BRANCH TRIBUTARY NO. 5 (WBW5)

5.0 INSURANCE APPLICATIONS For flood insurance rating purposes, flood insurance zone designations are assigned to a community based on the results of the engineering analyses. The zones are as follows: Zone A Zone A is the flood insurance rate zone that corresponds to the 00-year floodplains that are determined in the FIS by approximate methods. Because detailed hydraulic analyses are not performed for such areas, no base flood elevations or depths are shown within this zone. Zone AE Zone AE is the flood insurance rate zone that corresponds to the 00-year floodplains that are determined in the FIS by detailed methods. In most instances, whole-foot base flood elevations derived from the detailed hydraulic analyses are shown at selected intervals within this zone. Zone AH Zone AH is the flood insurance rate zone that corresponds to the areas of 00-year shallow flooding (usually areas of ponding) where average depths are between and 3 feet. Whole-foot base flood elevations derived from the detailed hydraulic analyses are shown at selected intervals within this zone. Zone AO Zone AO is the flood insurance rate zone that corresponds to the areas of 00-year shallow flooding (usually sheet flow on sloping terrain) where average depths are between and 3 feet. Average whole-depths derived from the detailed hydraulic analyses are shown within this zone. Zone AR Area of special flood hazard formerly protected from the % annual chance flood event by a flood control system that was subsequently decertified. Zone AR indicates that the former flood control system is being restored to provide protection from the % annual chance or greater flood event. Zone A99 Zone A99 is the flood insurance rate zone that corresponds to areas of the 00-year floodplain that will be protected by a Federal flood protection system where construction has reached specified statutory milestones. No base flood elevations or depths are shown within this zone. Zone V

Zone V is the flood insurance rate zone that corresponds to the 00-year coastal floodplains that have additional hazards associated with storm waves. Because approximate hydraulic analyses are performed for such areas, no base flood elevations are shown within this zone. Zone VE Zone VE is the flood insurance rate zone that corresponds to the 00-year coastal floodplains that have additional hazards associated with storm waves. Whole-foot base flood elevations derived from the detailed hydraulic analyses are shown at selected intervals within this zone. Zone X Zone X is the flood insurance rate zone that corresponds to areas outside the 500-year floodplain, areas within the 500-year floodplain, and to areas of 00-year flooding where average depths are less than foot, areas of 00-year flooding where the contributing drainage area is less than square mile, and areas protected from the 00-year flood by levees. No base flood elevations or depths are shown within this zone. Zone D Zone D is the flood insurance rate zone that corresponds to unstudied areas where flood hazards are undetermined, but possible. 6.0 FLOOD INSURANCE RATE MAP The FIRM is designed for flood insurance and floodplain management applications. For flood insurance applications, the map designates flood insurance rate zones as described in Section 5.0 and, in the 00-year floodplains that were studied by detailed methods, shows selected whole-foot base flood elevations or average depths. Insurance agents use the zones and base flood elevations in conjunction with information on structures and their contents to assign premium rates for flood insurance policies. For floodplain management applications, the map shows by tints, screens, and symbols, the 00- and 500-year floodplains. Floodways and the locations of selected cross sections used in the hydraulic analyses and floodway computations are shown where applicable. The current FIRM presents flooding information for the entire geographic area of DuPage County. Previously, separate Flood Hazard Boundary Maps and/or FIRMs were prepared for each identified flood-prone incorporated community and the unincorporated areas of the county. This countywide FIRM also includes flood hazard information that was presented separately on Flood Boundary and Floodway Maps (FBFMs), where applicable. Historical 82

data relating to the maps prepared for each community, up to and including this countywide FIS, are presented in Table 7, "Community Map History." 7.0 OTHER STUDIES FISs have been prepared for Kane County and incorporated areas ( ), Will County and incorporated areas ( ), and Cook County and incorporated areas ( ). Information pertaining to revised and unrevised flood hazards for each jurisdiction within DuPage County has been compiled into this FIS. Therefore, this FIS supersedes all previously printed FIS Reports, FHBMs, FBFMs, and FIRMs for all of the incorporated and unincorporated jurisdictions within DuPage County. Following is a list of reports and studies pertaining to the flood hazards within DuPage County: Flood Water Management Plan of the Des Plaines River Floodplain Maps and Flood Profiles for Salt Creek and Westwood Creek A Flooding and Storm Sewer Report USGS Publication Water Resources Data for Illinois, Part, Surface Water Records Floodplain Information Report, West Branch DuPage River, Kress Creek and Klein Creek, Cook County, Illinois An SCS Study for the Des Plaines River Basin Illinois Department of Transportation, Division of Water Resources report, Strategic Planning Study for Flood Control Bensenville Ditch, Bensenville, Illinois, DuPage County Donohue & Associates, Inc., study for Addison Creek Stormwater Management System Evaluation, DuPage and Cook Counties, Illinois Survey Report for Improvement for Spring Brook Creek Spring Brook Drainage Study West Branch Tributary to Spring Brook Creek Drainage Basin Study Engineer s Report, Stormwater Management Plan for the Klein Creek Basin Segment of the Bloomingdale West Project Storm Water Management Plan, a part of the Klein Creek segment of the Bloomingdale West Project Surface Water Drainage Study of the Indian Lakes Subdivision and Environs Flood Plain Information Study on the Des Plaines River and its tributaries Lindley and Sons, Inc., Drainage Study on a tributary to the 63 rd Street Ditch and on 79 th Street Ditch for the Village of Burr Ridge Baranecki, Vigilio, and Associates, Improvement Plan for Burr Ridge Illinois Division of Water Resources, Strategic Planning Study of the Winfield Creek Basin Floodplain maps and flood profiles for Sawmill Creek and East Branch Sawmill Creek 83

Special Flood Hazard Information Study for the East Branch DuPage River, Prentiss Creek, St. Joseph Creek, and Lacey Creek USGS Hydrologic Investigations Atlases USGS Flood-Prone Area Maps Special Flood Hazard Information Study of the East Branch DuPage River A report by Harza Engineering, Village of Hanover Park, Illinois, West Branch DuPage River Flood Control Plan Floodwater Management Plan for the Des Plaines River Watershed Upper Salt Creek Watershed Work Plan Des Plaines River Watershed Floodwater Management Plan and Flood Plain Information, Maps and Profiles USACE, Chicago District, East Branch DuPage River Special Flood Hazard Information Report A report by the State of Illinois Department of Public Works and Buildings, Division of Waterways West Branch DuPage River Flood Plain Information Report A report analyzing flooding along Salt Creek, updated by the IDOT A Flood Hazard Information Report by Carl C. Crane, Inc., for the Chicago District USACE A Plan of Study report on the Fox River and its tributaries Southeastern Wisconsin Regional Planning Commission Report Work Plan for Watershed Protection and Flood Prevention, Upper Salt Creek Watershed Report on the Regulation of Construction Within the Flood Plain of Upper Salt Creek and Tributaries, Palatine, Schaumburg, Elk Grove Township, Cook County, Illinois Des Plaines River Flood Plain Information Maps and Profiles Regulation of Construction Within the Flood Plain of the Lower Salt Creek and Tributaries of Cook and DuPage Counties A Comprehensive Plan for the Fox River Surface Water Drainage Control Study for the Village of Westmont Des Plaines River Flood Plain Information Maps and Profiles, Cook and DuPage Counties, Illinois Stormwater Management Study, Village of Willowbrook Lindley and Sons, Inc., Several Letter Reports to the City of Darien, Illinois, on Lake Hinsdale and Sawmill Creek SCS publication, Upper Salt Creek Watershed Work Plan of the Busse Woods Reservoir City of Wood Dale Comprehensive Storm Drainage Report

8.0 LOCATION OF DATA Information concerning the pertinent data used in the preparation of this FIS can be obtained by contacting FEMA, Federal Insurance and Mitigation Division, 536 South Clark Street, Sixth Floor, Chicago, Illinois 60605. 9.0 BIBLIOGRAPHY AND REFERENCES American Guide Series. (94). DuPage County: A Descriptive and Historical Guide, 83-939. Baranecki, Vigilio, and Associates. (December 977). Improvement Plans for Burr Ridge Meadows, Phase I. Burr Ridge, Illinois. Barton-Aschman Associates, Inc. (August 976). First Year Planning Program, Reconnaissance Study. Baxter and Woodman, Inc. (January 976). Winfield Creek Drainage Investigation: Engineer s Report. Crystal Lake, Illinois. Baxter and Woodman, Inc. (October 975). Winfield Creek Retention Study. Crystal Lake, Illinois. Chow, V. T. (964). Handbook of Applied Hydrology. McGraw Hill Book Company, Inc. Chow, V. T. (959). Open Channel Hydraulics. McGraw Hill Book Company, Inc. Damage Estimate Set. (August 29, 972). The Daily Journal, Volume 40, No. 226, Page. Des Plaines River Watershed Steering Committee, and U.S. Department of Agriculture, Soil Conservation Service. (976). Des Plaines River Floodwater Management Plan and Environmental Assessment. Des Plaines River Watershed Steering Committee. (December 975). Des Plaines River Flood Plain Information Maps and Profiles, Cook and DuPage Counties, Illinois. Dougherty, R. L., and J. B. Fanzini. (977). Fluid Mechanics with Engineering Applications. McGraw-Hill Book Company, Inc. Downers Grove Reporter. (October 4, 954; July 8, 957; and August 3, 972). Downers Grove, Illinois. DuPage County Zoning Ordinance. (December 0, 935, as amended). DuPage County Board of Supervisors. 86

Federal Emergency Management Agency. (April 982). Flood Insurance Study, DuPage County, Illinois (Unincorporated Areas). Federal Emergency Management Agency, Federal Insurance Administration. (February 8, 98). Flood Insurance Study, City of Oak Brook Terrace, DuPage County, Illinois. Washington, D.C. Federal Emergency Management Agency, Federal Insurance Administration. (February 98). Flood Insurance Study, Village of Villa Park, Illinois. Washington, D.C. Federal Emergency Management Agency, Federal Insurance Administration. (April 98). Flood Insurance Study, Village of Downers Grove, Illinois. Federal Emergency Management Agency, Federal Insurance Administration. (May 98). Flood Insurance Study, Village of Roselle, Illinois. Washington, D.C. Federal Emergency Management Agency, Federal Insurance Administration. (October 98). Flood Insurance Study, Village of Burr Ridge, Illinois. Washington, D.C. Federal Emergency Management Agency, Federal Insurance Administration. (January 980). Flood Insurance Study, Village of Willowbrook, Illinois. Washington, D.C. Federal Emergency Management Agency, Federal Insurance Administration. (September 980). Flood Insurance Study, Village of Lisle, Illinois. Washington, D.C. Federal Emergency Management Agency, Federal Insurance Administration. (June 979). Flood Insurance Study, City of Wheaton, Illinois. Washington, D.C. Federal Emergency Management Agency, Federal Insurance Administration. (October 978). Flood Insurance Study, Village of Lombard, Illinois. Washington, D.C. Federal Emergency Management Agency, Federal Insurance Administration. (October 977). Flood Insurance Study, Village of Itasca, Illinois. Washington, D.C. Federal Emergency Management Agency, Federal Insurance Administration. (In progress). Flood Insurance Study, Village of Downers Grove, Illinois. Washington, D.C. Federal Emergency Management Agency, Federal Insurance Administration. (In progress). Flood Insurance Study, City of Elmhurst, Illinois. Washington, D.C. Federal Emergency Management Agency, Federal Insurance Administration. (November 6, 2000). Flood Insurance Study, Cook County, Illinois (Unincorporated Areas). Washington, D.C. Floodplain Topographic Maps. (Champaign, Illinois, 973). Salt Creek Watershed, Scale :4,800, Contour Interval 2 feet. Soil Conservation Service. Glen Ellyn News. (August 30, 972).

Hansen, Harry (editor). (974). Illinois, A Descriptive and Historical Guide. New York, Hastings House. Harza Engineering Company. (97). West Branch DuPage River Flood Control Plan. Chicago, Illinois. Illinois Department of Public Works and Buildings, Division of Waterways. (962). Survey Report for Flood Control, DuPage River, DuPage and Will Counties. Illinois Department of Transportation, Division of Water Resources. (January 980). Regulation of Construction Within the Floodplain of Lower Salt Creek and Tributaries. Springfield, Illinois. Illinois Department of Transportation, Division of Water Resources. (Cook, DuPage, and Lake Counties, Illinois, July 979). Regulatory Floodplain, Lower Salt Creek, Scale :400, Contour Interval 4 feet. Illinois Department of Transportation, Division of Water Resources. (975). Strategic Planning Study of Waubansee Creek from Montgomery to Oswego, Kane and Kendall Counties, Illinois. Illinois Department of Transportation, Division of Water Resources. (Springfield, Illinois, 973, and revised statutes, Chapter 9, 52 et seq., 975). Rules and Regulations, Regulations of Construction Within Floodplains Established Pursuant to Section 654, Chapter 9, Illinois Revised Statutes. Illinois Department of Transportation, Division of Water Resources. (973). Magnitude and Frequency of Floods in Illinois. J. M. Carns (author). Springfield, Illinois. Illinois Department of Transportation, Division of Water Resources. (973). Rules and Regulations, Regulation of Construction Within Flood Plains Established Pursuant to Section 65F, Chapter 9, Illinois Revised Statutes. Springfield, Illinois. Illinois Division of Water Resources. (977). Guidelines for Operational Procedures at McHenry Dam. Lardner, J. P. and M. L. Terstriep. (November 975). Illinois State Water Survey, Waubansee Creek Floodplain Analysis. Lindley and Sons, Inc. (February 974). Northcentral Storm Drainage Report. Naperville, Illinois. Mackie Consultants, Inc. (977). Engineers Report, Stormwater Management Plan for the Klein Creek Basin Segment of the Bloomingdale West Project. 88

North Central Chicago Engineering Division-Hydraulics. (978). Memorandum for File, Fox River, Special Flood Hazard Study Chain of Lakes, McHenry and Lake Counties, Illinois. Northeastern Illinois Planning Commission. (Village of Downers Grove, Illinois, flown in March-April 975). Topographic Maps compiled from air photos, Scale :,200, Contour Interval Foot. Northeastern Illinois Planning Commission, in cooperation with the Chicago District, U.S. Army Corps of Engineers. (West Branch DuPage River, Cook and Will Counties, Illinois; Madison, Wisconsin, Alster and Associates, Inc., Photographed April 6, 974). Flood Plain Topographic Maps, Scale :4,800. Northeastern Illinois Planning Commission. (April 973). Suburban Factbook. Southeastern Wisconsin Regional Planning Commission. (April 969). Planning Report No. 2, Volumes One and Two. A Comprehensive Plan for the Fox River Watershed. Waukesau, Wisconsin. State of Illinois, Office of the Secretary of State. (976). Springfield, Illinois. State of Illinois. (July 976). Counties and Incorporated Municipalities of Illinois. State of Illinois, Department of Transportation, Division of Water Resources. (Madison, Wisconsin, September 976). DuPage River Flood Plain, Scale :4,800, Contour Interval 2 feet. Alster & Associates Engineering. State of Illinois, Department of Transportation, Division of Water Resources. (Sheboygan, Wisconsin, December 975). Flood Plain Topographic Map for Salt Creek Watershed, Scale :4,800, Contour Interval 4 feet. Aero-Metric Engineering, Inc. State of Illinois, Department of Public Works and Buildings, Division of Waterways (currently Department of Transportation, Division of Water Resources). (975). Survey Report for Development of Fox River, Ottawa to McHenry Dam, La Salle, Kane, Kendall, McHenry, and Lake Counties, Illinois. State of Illinois, Department of Transportation, Division of Water Resources. (December 975). Preliminary Report on the Regulation of Construction with the Floodplain of Waubansee Creek and Tributary. State of Illinois, Department of Transportation, Division of Water Resources. (973). Magnitude and Frequency of Floods in Illinois. J. M. Carns (author). Springfield, Illinois. State of Illinois, State Water Survey. (October 975). Poplar Creek Flood Plain Report. J. M. Jess (author). Springfield, Illinois. 89

State of Illinois, Department of Public Works and Buildings, Division of Waterways. (962). Survey Report for Flood Control, DuPage River, DuPage and Will Counties, Illinois. Chicago, Illinois. State of Illinois, Department of Public Works and Buildings, Division of Waterways (currently Department of Transportation, Division of Water Resources). (960). Survey Report for Flood Control, Indian Creek and Tributaries, Aurora and Vicinity, Kane County, Illinois. State of Illinois, Department of Public Works and Buildings, Division of Waterways (currently Department of Transportation, Division of Water Resources). (954). Floods in Illinois, Magnitude and Frequency. W. D. Mitchell (author). University of Illinois, Department of Agronomy, Agricultural Experiment Station. (950). AG-443, Illinois Soil Type Descriptions. Y. L. Wascher, J. B. Fehrenbacher, R. T. Odell, and P. T. Veale (authors). U.S. Army Corps of Engineers, Hydrologic Engineering Center. (May 99). HEC-2 Water-Surface Profiles, Generalized Computer Program. Davis, California. U.S. Army Corps of Engineers, Chicago District. (Unincorporated Areas of Kane County, Illinois, September-October 978). Topographic Maps, Scale :4,800, Contour Interval four feet. U.S. Army Corps of Engineers, Chicago District. (October 977). Preliminary Environmental Inventory. DuPage Basin Study Area. U.S. Army Corps of Engineers. (November 976). HEC-2 Water-Surface Profiles. U.S. Army Corps of Engineers, Chicago District. (976). A Plan of Study for the Fox River and its Tributaries. Chicago, Illinois. U.S. Army Corps of Engineers, Chicago District. (June 975). Flood Plain Information, West Branch DuPage River, Kress Creek, Klein Creek, DuPage County, Illinois. U.S. Army Corps of Engineers, Hydrologic Engineering Center. (June 974). Balanced Hydrograph Techniques for Five Selected Basins in the Chicago Metropolitan Area Memo No. 428. U.S. Army Corps of Engineers, Hydrologic Engineering Center. (January 973). HEC- Flood Hydrograph Package, Computer Program, 723-X6-L200. Davis, California. U.S. Army Corps of Engineers, Hydrologic Engineering Center. (September 973). Special Project Memo No. 42, Des Plaines River Basin, Duplicate Lock Hydrology Study. 90

U.S. Army Corps of Engineers, Hydrologic Engineering Center. (October 973). HEC Special Project Memo No. 45, Chicago Metropolitan Area Study, DuPage River Basin. U.S. Army Corps of Engineers, Hydrologic Engineering Center. (October 973). HEC-2 Water-Surface Profiles, Computer Program 723-X6-L202A. Davis, California. U.S. Army Corps of Engineers, Hydrologic Engineering Center. (February 972). HEC- 2 Water-Surface Profiles, Computer Program 723-X6-L202A. Davis, California. U.S. Department of Agriculture, Soil Conservation Service. (April 979). Soil Survey of Kane County, Illinois. U.S. Department of Agriculture, Soil Conservation Service. (June 978). Floodway Determination Computer Program, Technical Release 64. U.S. Department of Agriculture, Soil Conservation Service, Central Technical Unit. (977). HUD-5 Computer Program. Hyattsville, Maryland. U.S. Department of Agriculture, Soil Conservation Service. (May 976). Technical Release No. 6, WSP-2 Computer Program. Washington, D.C. U.S. Department of Agriculture, Soil Conservation Service. (January 975). Technical Release No. 55, Urban Hydrology for Small Watersheds. U.S. Department of Agriculture, Soil Conservation Service. (June 974). WSP-2 Water- Surface Profiles Users Manual. R. Pasley and O. Lee (authors). U.S. Department of Agriculture, Soil Conservation Service. (February 974). SCS TR- 20 Project Formulation Computer Program. Champaign, Illinois. U.S. Department of Agriculture, Soil Conservation Service. (March 974). WSP-2 Water-Surface Profile Computer Program. Champaign, Illinois. U.S. Department of Agriculture, Soil Conservation Service. (973). Work Plan for Watershed Protection and Flood Prevention, Upper Salt Creek Watershed. Lincoln, Nebraska. U.S. Department of Agriculture, Soil Conservation Service. (965). Technical Release No. 20, Computer Program, Project Formulation, Hydrology. Washington, D.C. U.S. Department of Agriculture, Soil Conservation Service. (December 963). Guide for Selecting Roughness Coefficients. Champaign, Illinois. U.S. Department of Commerce, National Oceanic and Atmospheric Administration, Environmental Data Service. (977). Climatological Data, Illinois. Asheville, North Carolina. 9

U.S. Department of Commerce, National Oceanic and Atmospheric Administration. (976). Local Climatological Data for Chicago, Illinois. U.S. Department of Commerce. (March 976). Bulletin No. 7, Guidelines for Determining Flood Flow Frequency. Washington, D.C. U.S. Department of Commerce, National Oceanic and Atmospheric Administration. (975). Climatological Data, Illinois, Annual Summary, 974, Volume 79, Number 3. U.S. Department of Commerce, Bureau of the Census. (97). Census of Population, Number of Inhabitants, Illinois. Washington, D.C. U.S. Department of Commerce, Bureau of the Census. (June 970). Current Population Report, Series P-28, No. 552. U.S. Government Printing Office. Washington, D.C. U.S. Department of Commerce, Weather Bureau. (963). Technical Paper No. 40, Rainfall Frequency Atlas of the United States (for Durations from 30 minutes to 24 hours and return periods from 7 to 00 years). Washington, D.C. U.S. Department of Commerce, Weather Bureau. (June 962). Climatic Guide for Chicago, Illinois, Area. U.S. Department of Commerce, National Weather Service. (May 96). Rainfall Frequency Atlas of the United States, Technical Paper No. 40. U.S. Government Printing Office. Washington, D.C. U.S. Department of Commerce, Bureau of Public Roads. (September 96). Hydraulic Charts for the Selection of Highway Culverts, Hydraulic Engineering Circular No. 5. U.S. Government Printing Office. Washington, D.C. U.S. Department of Housing and Urban Development, Federal Insurance Administration. (November 6, 2000). Flood Insurance Study, Indian Head Park, Illinois. U.S. Department of Housing and Urban Development, Federal Insurance Administration. (January 979). Flood Insurance Study, Village of Glen Ellyn, Illinois. Washington, D.C. U.S. Department of Housing and Urban Development, Federal Insurance Administration. (November 979). Flood Insurance Study, City of West Chicago, Illinois. Washington, D.C. U.S. Department of Housing and Urban Development, Federal Insurance Administration. (March 979). Flood Insurance Study, Village of Addison, Illinois. Washington, D.C. U.S. Department of Housing and Urban Development, Federal Insurance Administration. (June 979). Flood Insurance Study, Village of Woodbridge, Illinois. 92

U.S. Department of Housing and Urban Development, Federal Insurance Administration. (June 979). Flood Insurance Study, City of Aurora, Illinois. U.S. Department of Housing and Urban Development, Federal Insurance Administration. (March 979). Flood Insurance Study, City of Naperville, Illinois. U.S. Department of Housing and Urban Development, Federal Insurance Administration. (May 978). Flood Insurance Study, Village of Hanover Park, Cook and DuPage Counties, Illinois. Washington, D.C. U.S. Department of Housing and Urban Development, Federal Insurance Administration. (August 978). Flood Insurance Study, Village of Glendale Heights, Illinois. U.S. Department of Housing and Urban Development, Federal Insurance Administration. (May 977). Flood Hazard Boundary Map, DuPage County, Illinois (Unincorporated Areas). Washington, D.C. U.S. Department of Housing and Urban Development, Federal Insurance Administration. (October 24, 975). Flood Hazard Boundary Map, Village of Schaumburg, Cook County, Illinois. U.S. Department of the Interior, Geological Survey. (979). Effects of Urbanization on the Magnitude and Frequency of Floods in Northeastern Illinois, 79-36. U.S. Department of the Interior, Geological Survey. (978). Water Resources Data for Illinois, Water Year 977. U.S. Department of the Interior, Geological Survey. (977). Water Resources Investigations 77-7, Technique for Estimating Magnitude and Frequency of Floods in Illinois. U.S. Department of the Interior, Geological Survey. (Hinsdale Quadrangle, 976). Hydrologic Atlas 86, Flood Plain Map, Scale :2,400, Contour Interval 5 Feet. U.S. Department of the Interior, Geological Survey. (975). Water Resources Data for Illinois, Part, Surface Water Records. Champaign, Illinois. U.S. Department of the Interior, Geological Survey. (974). Determination of 00-year Flood Flows in Urbanizing Regions of Northeastern Illinois. Champaign, Illinois. U.S. Department of the Interior, Geological Survey. (973). 972 Water Resources Data for Illinois. U.S. Department of the Interior, Geological Survey, in cooperation with the State of Illinois Department of Transportation, Division of Water Resources. (973). Magnitude and Frequency of Floods in Illinois. Jack M. Carns (author). Springfield, Illinois. 93

U.S. Department of the Interior, Geological Survey. (973). Water Resources Data for Illinois: 972. Champaign, Illinois. U.S. Department of the Interior, Geological Survey. (Naperville, 972; West Chicago, 972; Normantown, 973; Romeville, 973; Wheaton, 972; Lombard, 972; Elmhurst, 972; Hinsdale, 972; Sag Bridge, 973, Illinois). 7.5-Minute Series Topographic Maps, Scale :24,000, Contour Interval 0 feet. U.S. Department of the Interior, Geological Survey. (Hinsdale and Sag Bridge, Illinois, photorevised 972). 7.5-Minute Series Quadrangle Map, Scale :24,000, Contour Interval five feet. U.S. Department of the Interior, Geological Survey. (967). Water Supply Paper 849, Roughness Characteristics of Natural Channels. U.S. Government Printing Office. Washington, D.C. U.S. Department of the Interior, Geological Survey. (965). Hydrologic Investigations Atlases for West Chicago, HA202 and Naperville, HA54. U.S. Department of the Interior, Geological Survey. (965). Floods in Wheaton Quadrangle, Northeastern Illinois, Hydrologic Investigations Atlas HA-48. U.S. Department of the Interior, Geological Survey. (965). Floods in Romeoville Quadrangle, Northeastern Illinois, Hydrologic Investigations Atlas HA-46. U.S. Department of the Interior, Geological Survey. (Naperville, Illinois HA-54, 965; HA-20, 966; HA-48, 965, HA-46, 965). Hydrologic Investigations Atlases. H. E. Allen and V. Jeff May (authors). U.S. Department of the Interior, Geological Survey. (HA 43, 964, HA 202, 965). Hydrologic Investigations Atlases for Carol Stream, Scale :24,000, Contour Interval 0 feet. U.S. Department of the Interior, Geological Survey. (964). Hydrologic Investigations Atlas, HA-87, Floods in the Palatine Area Floods in the Palatine Area. Howard E. Allen and others (authors). U.S. Department of the Interior, Geological Survey. (964 and 965). Hydrologic Investigation Atlases, HA-43 and HA-48. U.S. Department of the Interior, Geological Survey. (963). Floods in Aurora North Quadrangle, Illinois, Hydrologic Investigations Atlas, HA-70. U.S. Department of the Interior, Geological Survey. (Hinsdale, Illinois, 963, Photorevised 972; Wheaton, Illinois, 962, Photorevised 972). Map of Flood-Prone Areas, Scale :24,000, Contour Interval 20 Feet. 94

U.S. Department of the Interior, Geological Survey. (Elmhurst, Illinois, 963, photorevised 972 and 980). 7.5-Minute Series Topographic Maps, Scale :24,000, Contour Interval 0 feet. U.S. Department of the Interior, Geological Survey. (Hinsdale Quadrangle, Illinois, 963). Hydrologic Investigations Atlas, HA-86, Scale :24,000, Contour Interval 0 Feet. U.S. Department of the Interior, Geological Survey. (Sag Bridge Quadrangle, Illinois, 963). Hydrologic Investigations Atlas, HA-49, Scale :24,000, Contour Interval 5 Feet. U.S. Department of the Interior, Geological Survey. (962 to present). St. Charles Gage Station, No. 0555220. U.S. Water Resources Council. (March 976). Bulletin No. 7, Guidelines for Determining Flood Flow Frequency. U.S. Water Resources Council, (December 967). Determining Flood Flow Frequencies, Bulletin No. 5. A Uniform Technique for Village of Carol Stream, Village Hall. (January 980). Carol Stream 979 Census. Village of Bloomingdale, DuPage County, Illinois. (March 24, 975). 75-0, An Ordinance Regulating the Interference with Storm Ditches and Requiring a Permit Therefore. Village of Willowbrook. (974). Zoning Map. Village of Bloomingdale, DuPage County, Illinois. (June 973). 73-9, An Ordinance Providing Stormwater Retention Requirements. Wheaton Experiences Much Loss. (October, 954). The Daily Journal, Volume 22, No. 07, page. Wight Consulting Engineers, Inc. (978). Surface Water Drainage Study, Indian Lakes Subdivision and Environs. Bloomingdale, Illinois. Wight and Company. (977). Stormwater Management Study, Village of Willowbrook. Woodward, Sherman M. and Chesley I. Posey. (94). Hydraulics of Steady Flow in Open Channels. John Wiley and Sons. 95

ELEVATION IN FEET (NGVD 29) LIMIT OF FLOODING AFFECTING COUNTY COUNTY LINE ROAD BRIDGE 2 CEMETARY ROAD CEMETERY ROAD GRAND AVENUE UNNAMED ROAD 665 665 660 660 655 655 CULVERT CULVERT 650 650 GEORGE STREET GEORGE STREET RESERVOIR LIMIT OF DETAILED STUDY THE 50-YEAR FLOOD PROFILE UPSTREAM OF STATION 66, 83 IS NOT AVAILABLE ADDISON CREEK (DPAC) 645 645 640 640 635 COUNTY BOUNDARY DPAC000 DPAC0002 DPAC0003 DPAC0004 DPAC0005 630 6000 6500 62000 62500 63000 63500 64000 64500 65000 65500 66000 66500 67000 67500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER DPAC0006 DPAC0007 DPAC0008 DPAC0009 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 0P

00-YEAR BACKWATER FROM DES PLAINES RIVER ELEVATION IN FEET (NGVD 29) 620 620 CONFLUENCE WITH DES PLAINES RIVER RAILROAD 65 65 60 60 605 605 600 600 FOREST PRESERVE ROAD SAWMILL CREEK TRIBUTARY NO. 3 (DPDP) 595 595 590 590 585 DPDP00 580 0 200 400 600 800 000 200 400 600 800 2000 2200 2400 2600 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER DPDP002 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 0P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH GINGER CREEK ROYAL VALE DRIVE LIMIT OF 705 705 700 700 695 695 LOMBARD TRIBUTARY (SCGC) 690 690 685 685 680 SCGC5054 SCGC5056 675 0 200 400 600 800 000 200 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH GINGER CREEK 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* *DATA NOT AVAILABLE 00P

00-YEAR BACKWATER FROM GINGER CREEK ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH GINGER CREEK 685 685 CONCRETE WEIR CONCRETE WEIR 680 680 675 675 670 670 CONCRETE WEIR 665 665 MAYS LAKE TRIBUTARY (SCGC) 660 660 655 655 650 645 0 500 000 500 2000 SCGC507 SCGC5028 SCGC5026 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH GINGER CREEK 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* *DATA NOT AVAILABLE 0P

720 720 ELEVATION IN FEET (NGVD 29) 75 75 CONCRETE WEIR OAK BROOK ROAD LIMIT OF MAYS LAKE II WEIR 70 70 705 705 700 700 CULVERT 695 695 LIMIT OF DETAILED STUDY MAYS LAKE TRIBUTARY (SCGC) 690 690 685 685 680 CULVERT SCGC5057 SCGC5058 675 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 MAYS LAKE I CULVERT STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH GINGER CREEK 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* *DATA NOT AVAILABLE 02P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH GINGER CREEK OAK BROOK ROAD LIMIT OF DETAILED STUDY 70 70 705 705 700 700 MIDWEST CLUB TRIBUTARY (SCGC) 695 695 690 690 685 SCGC5066 SCGC5065 SCGC5064 680 0 500 000 500 2000 2500 3000 SCGC5063 SCGC5062 SCGC506 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH GINGER CREEK 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* *DATA NOT AVAILABLE 03P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH SALT CREEK 685 685 SPRING ROAD ACCESS ROAD ACCESS ROAD STATE ROUTE 83 680 680 675 675 670 670 665 665 HODGES ROAD PARK ROAD KARBAN ROAD SPRING ROAD TRIBUTARY (SCOB) 660 660 655 655 650 SCOB000 SCOB0002 SCOB0003 SCOB0004 SCOB0005 645 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 SCOB0006 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCOB0007 SCOB0008 SCOB0009 SCOB000 SCOB00 SCOB002 SCOB003 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 04P

ELEVATION IN FEET (NGVD 29) 705 705 MACARTHUR DRIVE EISENHOWER ROAD 700 700 695 695 CULVERT MIDWEST ROAD LIMIT OF DETAILED STUDY 690 690 685 685 SPRING ROAD TRIBUTARY (SCOB) 680 680 675 675 670 SCOB004 SCOB005 SCOB006 665 6500 7000 7500 8000 8500 9000 9500 SCOB007 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 05P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH SALT CREEK N. PROSPECT AVENUE 690 690 680 680 SPRING BROOK CREEK (SCSB) 670 670 660 660 650 SCSB000 SCSB0002 SCSB0003 640 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCSB0004 SCSB0005 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD SCSB0006 06P

ELEVATION IN FEET (NGVD 29) RAILROAD ROUTE 9 (IRVING PARK BLVD) MAPLE AVENUE INTERSTATE 290 (NORTHBOUND) INTERSTATE 290 (SOUTHBOUND) 690 690 SPRING BROOK CREEK (SCSB) 680 680 670 670 660 SCSB0007 SCSB0008 SCSB0009 650 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCSB000 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD SCSB00 07P

ELEVATION IN FEET (NGVD 29) 70 70 700 700 LAKE KADIJAH SPILLWAY CONFLUENCE OF MEACHAM CREEK SPRING BROOK CREEK (SCSB) 690 690 680 680 670 SCSB002 SCSB003 660 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 9000 9500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCSB004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 08P

ELEVATION IN FEET (NGVD 29) MEDINAH ROAD MEDINAH-ON-THE-LAKE ROAD LAKEVIEW DRIVE 720 720 70 70 SPRING BROOK CREEK (SCSB) 700 700 690 690 680 SCSB005 670 9500 20000 20500 2000 2500 22000 22500 23000 23500 24000 24500 25000 25500 26000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCSB006 SCSB007 SCSB008 SCSB009 SCSB0020 SCSB002 SCSB0022 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 09P

ELEVATION IN FEET (NGVD 29) 645 645 640 640 635 635 630 630 625 625 SAWMILL CREEK TRIBUTARY NO. 3 (DPDP) 620 620 65 65 60 DPDP003 605 2600 2800 3000 3200 3400 3600 3800 4000 4200 4400 4600 4800 5000 5200 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER DPDP004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD P

ELEVATION IN FEET (NGVD 29) CIRCLE AVENUE GRAVEL ROAD FARM ROAD 730 730 720 720 CONFLUENCE OF WEST BRANCH TRIBUTARY TO SPRING BROOK CREEK SPRING BROOK CREEK (SCSB) 70 70 700 700 690 SCSB0023 SCSB0024 SCSB0025 SCSB0026 SCSB0027 SCSB0028 SCSB0029 SCSB0030 SCSB003 680 26000 26500 27000 27500 28000 28500 29000 29500 30000 30500 3000 3500 32000 32500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCSB0032 SCSB0033 SCSB0034 SCSB0035 SCSB0036 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD SCSB0037 0P

ELEVATION IN FEET (NGVD 29) FOSTER AVENUE PRIVATE DRIVE WALNUT STREET 760 760 750 750 740 740 730 730 ROSELLE ROAD TURNER AVENUE BRYN MAWR AVENUE SPRING BROOK CREEK (SCSB) 720 720 70 70 700 SCSB0038 SCSB0039 SCSB0040 SCSB004 SCSB0042 SCSB0043 SCSB0044 690 32500 33000 33500 34000 34500 35000 35500 36000 36500 37000 37500 38000 SCSB0045 SCSB0046 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCSB0047 SCSB0048 SCSB0049 SCSB0050 SCSB005 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD P

ELEVATION IN FEET (NGVD 29) PINE AVENUE MAPLE AVENUE WILLOW STREET ELM AVENUE HILL STREET 800 800 790 790 780 CULVERT 780 CULVERT 770 770 CENTRAL AVENUE LIMIT OF DETAILED STUDY SPRING BROOK CREEK (SCSB) 760 760 750 750 740 SCSB0052 CULVERT SCSB0053 SCSB0054 SCSB0055 SCSB0056 730 38000 38500 39000 39500 40000 40500 4000 4500 42000 42500 43000 43500 44000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCSB0057 SCSB0058 SCSB0059 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 2P

755 755 ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH SPRING BROOK CREEK BLOOMINGDALE ROAD 750 750 745 745 740 740 735 735 CULVERT 730 730 MAPLE AVENUE LIMIT OF DETAILED STUDY WEST BRANCH TRIBUTARY TO SPRING BROOK CREEK (SCSB) 725 725 720 720 75 SCSB0060 SCSB006 SCSB0062 70 0 500 000 500 2000 2500 3000 3500 4000 4500 SCSB0063 SCSB0064 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SPRING BROOK CREEK SCSB0065 SCSB0066 SCSB0067 SCSB0068 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 3P

ELEVATION IN FEET (NGVD 29) 720 720 75 75 70 70 705 705 700 700 695 695 690 690 685 CONFLUENCE WITH SPRING BROOK CREEK LAKE KADIJAH MEDINAH MOUTH COUNTRY CLUB ROAD SCSB0069 680 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SPRING BROOK CREEK SCSB0070 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD IRVING PARK BOULEVARD SCSB007 MEACHAM CREEK (SCSB) 4P

ELEVATION IN FEET (NGVD 29) RAILROAD MAPLE AVENUE THORNDALE AVENUE 725 725 720 720 75 75 70 70 MEDINAH ROAD LIMIT OF DETAILED STUDY MEACHAM CREEK (SCSB) 705 705 700 700 695 SCSB0072 SCSB0073 690 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 SCSB0074 SCSB0075 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SPRING BROOK CREEK SCSB0076 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 5P

COUNTY BOUNDARY COUNTY BOUNDARY COUNTY BOUNDARY 650 650 SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 645 645 640 640 635 635 630 630 625 SCSC000 620 47500 48000 48500 49000 49500 50000 50500 5000 5500 52000 52500 53000 53500 54000 STREAM DISTANCE IN FEET ABOVE MOUTH 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 6P

YORK ROAD FULLERSBURG DAM SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 650 650 645 645 640 640 635 635 630 SCSC0002 SCSC026 SCSC027 625 54000 54500 55000 55500 56000 56500 57000 57500 58000 58500 59000 59500 60000 60500 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC028 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD SCSC029 7P

CONFLUENCE OF BRONSWOOD CEMETARY TRIBUTARY 3ST STREET CONFLUENCE OF GINGER CREEK 660 SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 655 655 650 650 645 645 640 640 635 SCSC030 630 60500 6000 6500 62000 62500 63000 63500 64000 64500 65000 65500 66000 66500 67000 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC03 SCSC033 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 8P

670 670 665 665 660 660 22ND STREET SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 655 655 650 650 645 645 640 640 635 SCSC034 630 67000 67500 68000 68500 69000 69500 70000 70500 7000 7500 72000 72500 73000 73500 SCSC035 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC036 SCSC037 SCSC039 SCSC040 SCSC04 SCSC042 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 9P

ELEVATION IN FEET (NGVD 29) BLUFF ROAD EASTWOOD DRIVE 665 665 660 660 655 655 650 650 FRONT STREET CASS AVENUE SAWMILL CREEK TRIBUTARY NO. 3 (DPDP) 645 645 640 640 635 DPDP005 DPDP006 630 5200 5400 5600 5800 6000 6200 6400 6600 6800 7000 7200 7400 7600 7800 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER DPDP007 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 2P

680 680 ELEVATION IN FEET (NGVD 29) EAST WEST TOLLWAY (I-88) 675 675 670 670 INTERSTATE CONNECTOR HARGER ROAD 665 665 660 660 655 655 CONFLUENCE OF SPRING ROAD TRIBUTARY SALT CREEK (SCSC) 650 650 645 645 640 SCSC043 SCSC045 SCSC047 SCSC049 SCSC050 SCSC05 SCSC052 SCSC053 SCSC054 SCSC055 635 73500 74000 74500 75000 75500 76000 76500 77000 77500 78000 78500 79000 79500 80000 SCSC056 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC057 SCSC058 SCSC059 SCSC060 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD SCSC06 20P

ROOSEVELT ROAD FRONTAGE ROAD STATE ROUTE 56 (BUTTERFIELD ROAD) 665 665 SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 660 660 655 655 650 650 645 645 640 SCSC062 SCSC063 SCSC065 SCSC064 SCSC007 SCSC008 635 80000 80500 8000 8500 82000 82500 83000 83500 84000 84500 85000 85500 86000 86500 SCSC009 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC0020 SCSC002 SCSC0022 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 2P

CONFLUENCE OF SUGAR CREEK 675 675 670 670 RAILROAD ILLINOIS PRAIRIE PATH SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 665 665 660 660 655 655 650 650 645 SCSC0023 SCSC0024 SCSC0025 SCSC0026 640 86500 87000 87500 88000 88500 89000 89500 90000 90500 9000 9500 92000 92500 93000 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC0027 SCSC0028 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 22P

ST. CHARLES ROAD 680 680 675 675 RAILROAD RAILROAD 685 SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 670 670 665 665 660 660 655 655 650 SCSC0029 SCSC0030 SCSC003 645 93000 93500 94000 94500 95000 95500 96000 96500 97000 97500 98000 98500 99000 99500 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC0032 SCSC0033 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 23P

STATE ROUTE 64 (NORTH AVENUE) 680 680 KINGERY DIKE (SOUTH) TOP ELEVATION 675 675 SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 670 670 665 665 660 660 655 655 650 SCSC0034 SCSC0035 SCSC0036 645 99500 00000 00500 0000 0500 02000 02500 03000 03500 04000 04500 05000 05500 06000 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC0037 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 24P

FULLERTON AVENUE 680 680 KINGERY DIKE (NORTH) KINGERY DIKE (SOUTH) TOP ELEVATION TOP ELEVATION 675 675 LAKE STREET SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 670 670 665 665 660 660 655 655 650 SCSC0038 SCSC0039 645 06000 06500 07000 07500 08000 08500 09000 09500 0000 0500 000 500 2000 2500 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC0040 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 25P

CONFLUENCE OF WESTWOOD CREEK INTERSTATE 290 COUNTRY CLUB ROAD 680 680 SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 675 675 670 670 665 665 660 660 655 SCSC004 SCSC0042 650 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 9000 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC0043 SCSC0044 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE UPSTREAM OF SCSC0043 TO A POINT APPROXIMATELY,300 FEET DOWNSTREAM OF ELIZABETH ROAD 26P

COUNTRY CLUB ROAD 685 685 680 680 ELIZABETH DRIVE SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 675 675 670 670 665 665 660 660 655 650 9000 9500 20000 20500 2000 2500 22000 22500 23000 23500 24000 24500 25000 25500 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC0045 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE UPSTREAM OF SCSC0043 TO A POINT APPROXIMATELY,300 FEET DOWNSTREAM OF ELIZABETH ROAD SCSC0046 27P

690 690 685 685 (STATE ROUTE 9) IRVING PARK BOULEVARD RAILROAD SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 680 680 675 675 670 670 665 665 660 SCSC0047 655 25500 26000 26500 27000 27500 28000 28500 29000 29500 30000 30500 3000 3500 32000 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC0048 SCSC0049 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 28P

CONFLUENCE OF SPRING BROOK CREEK 685 685 SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 680 680 675 675 670 670 665 665 660 SCSC0050 SCSC005 655 32000 32500 33000 33500 34000 34500 35000 35500 36000 36500 37000 37500 38000 38500 STREAM DISTANCE IN FEET ABOVE MOUTH 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE UPSTREAM OF 200 FEET UPSTREAM OF SCSC0054 29P

ELEVATION IN FEET (NGVD 29) PARKING LOT ROAD 685 685 680 680 675 675 670 670 SAWMILL CREEK TRIBUTARY NO. 3 (DPDP) 665 665 660 660 655 DPDP008 DPDP009 650 7800 8000 8200 8400 8600 8800 9000 9200 9400 9600 9800 0000 0200 0400 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 3P

THORNDALE AVENUE COUNTY BOUNDARY LIMIT OF DETAILED STUDY SALT CREEK (SCSC) ELEVATION IN FEET (NGVD 29) 685 685 680 680 675 675 670 670 665 SCSC0055 SCSC0056 660 38500 39000 39500 40000 40500 4000 4500 42000 42500 43000 43500 44000 44500 45000 STREAM DISTANCE IN FEET ABOVE MOUTH SCSC0057 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE UPSTREAM OF 200 FEET UPSTREAM OF SCSC0054 30P

685 00-YEAR BACKWATER FROM SALT CREEK 680 675 CONFLUENCE WITH SALT CREEK RIVERSIDE DRIVE STATE ROUTE 83/ ROBERT KINGERY HIGHWAY FRONTAGE ROAD S. VILLA AVENUE S. EUCLID AVENUE SUMMIT AVENUE 670 670 SUGAR CREEK (SCSU) ELEVATION IN FEET (NGVD 29) 665 665 660 660 CULVERT 655 655 650 650 645 SCSU000 640 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCSU0002 SCSC0003 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD SCSU0004 3P

695 695 690 690 HARRISON STREET ARDMORE AVENUE 685 685 680 680 SUGAR CREEK (SCSU) ELEVATION IN FEET (NGVD 29) 675 675 RIORDON ROAD SCHOOL CROSSING CONFLUENCE OF SUGAR CREEK TRIBUTARY A 670 670 SCHOOL CROSSING SCHOOL CROSSING SCHOOL CROSSING LIMIT OF DETAILED STUDY 665 665 660 660 655 SCSU0005 SCSU0006 650 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 SCSU0007 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCSU0008 SCSU0009 SCSU000 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 32P

00-YEAR BACKWATER FROM SUGAR CREEK ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH SUGAR CREEK 70 70 705 705 700 700 695 695 CULVERT 690 690 ROOSEVELT ROAD LIMIT OF DETAILED STUDY SUGAR CREEK TRIBUTARY A (SCSU) 685 685 680 680 675 SCSU00 SCSU002 670 0 200 400 600 800 000 200 400 600 800 2000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SUGAR CREEK SCSU003 SCSU004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 33P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH SALT CREEK 695 695 N. ADDISON ROAD ROZANNE DRIVE N. LINCOLN AVENUE HIGHVIEW AVENUE LAKE STREET MILL ROAD 690 690 685 685 680 680 CULVERT 675 675 CONFLUENCE OF SOUTH FORK OF WESTWOOD CREEK COUNTRY CLUB DRIVE CULVERT LIMIT OF DETAILED STUDY WESTWOOD CREEK (SCWC) 670 670 665 665 660 SCWC000 CULVERT SCWC0002 CULVERT SCWC0003 CULVERT SCWC0004 CULVERT SCWC0005 655 0 000 2000 3000 4000 5000 6000 7000 8000 9000 0000 000 SCWC0006 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCWC0007 SCWC0008 SCWC0009 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 34P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH WESTWOOD CREEK ARMY TRAIL ROAD CONTROL STRUCTURE FULLERTON AVENUE LIMIT OF DETAILED STUDY 695 695 690 690 SOUTH FORK OF WESTWOOD CREEK (SCWC) 685 685 680 680 675 SCWC000 SCWC00 SCWC002 670 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WESTWOOD CREEK SCWC003 SCWC004 SCWC005 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 35P

630 630 00-YEAR BACKWATER FROM DES PLAINES RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH DES PLAINES RIVER 625 625 RAILROAD 620 620 65 65 60 60 605 605 SAWMILL CREEK (SWSW) 600 600 595 595 590 585 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER SWSW000 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 36P

660 660 655 655 ELEVATION IN FEET (NGVD 29) BLUFF ROAD 650 650 645 645 640 640 635 635 FRONT STREET EASTWOOD DRIVE SAWMILL CREEK (SWSW) 630 630 625 625 620 SWSW0002 65 5000 5500 6000 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD * DATA NOT AVAILABLE 37P

ELEVATION IN FEET (NGVD 29) CONFLUENCE OF WARDS CREEK 675 675 670 670 665 665 660 660 CASS AVENUE SAWMILL CREEK (SWSW) 655 655 650 650 645 SWSW0003 SWSW0004 640 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER SWSW0005 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD * DATA NOT AVAILABLE 38P

ELEVATION IN FEET (NGVD 29) CONFLUENCE OF SAWMILL CREEK TRIBUTARY NO. INTERSTATE 55 JOLIET ROAD 695 695 690 690 685 685 680 680 NANTUCKET DRIVE SAWMILL CREEK (SWSW) 675 675 670 670 665 SWSW0006 660 8000 8500 9000 9500 20000 20500 2000 2500 22000 22500 23000 23500 24000 24500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER SWSW0007 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD * DATA NOT AVAILABLE 39P

ELEVATION IN FEET (NGVD 29) 70 70 705 705 700 700 695 695 CLARENDON HILLS ROAD QUARTER LANE SAWMILL CREEK TRIBUTARY NO. 3 (DPDP) 690 690 685 685 680 DPDP0020 DPDP002 675 0400 0600 0800 000 200 400 600 800 2000 2200 2400 2600 2800 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER DPDP0022 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 4P

725 725 720 720 ELEVATION IN FEET (NGVD 29) 75 75 70 70 705 705 700 700 75TH STREET LIMIT OF DETAILED STUDY SAWMILL CREEK (SWSW) 695 695 690 690 685 SWSW0008 680 24500 25000 25500 26000 26500 27000 27500 28000 28500 29000 SWSW0009 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER SWSW000 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE DOWNSTREAM OF 25,000 FEET ABOVE CONFLUENCE WITH W. BRANCH DUPAGE RIVER 40P

730 730 ELEVATION IN FEET (NGVD 29) LIMIT OF DETAILED STUDY 725 725 JOLIETE ROAD WEIR 720 720 75 75 70 70 CULVERT NO. 705 705 COACHMAN ROAD CULVERT WEST BRANCH SAWMILL CREEK (SWSW) CULVERT 700 700 695 695 690 SWSW003 SWSW004 SWSW005 685 20000 20200 20400 20600 20800 2000 2200 2400 2600 2800 22000 22200 22400 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SAWMILL CREEK SWSW006 SWSW007 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 4P

ELEVATION IN FEET (NGVD 29) 740 740 735 735 730 730 CULVERT NO. 5 CULVERT NO. 4 725 725 CULVERT NO. 2 720 SWSW008 CULVERT NO. 3 SWSW009 SWSW0020 THE 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR PROFILE TO BE SHOWN SEPARATELY SWSW002 SWSW0022 75 22400 22600 22800 23000 23200 23400 23600 23800 24000 24200 24400 24600 24800 25000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SAWMILL CREEK LAKEVIEW DRIVE CULVERT SWSW0023 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WEST BRANCH SAWMILL CREEK (SWSW) 42P

ELEVATION IN FEET (NGVD 29) 760 760 755 755 750 750 745 745 LIMIT OF DETAILED STUDY WEST BRANCH SAWMILL CREEK (SWSW) 740 740 735 735 730 SWSW0024 725 25000 25200 25400 25600 25800 26000 26200 26400 26600 26800 SWSW0025 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SAWMILL CREEK SWSW0026 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 43P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH SAWMILL CREEK TRIBUTARY NO 725 725 720 720 75 75 79TH STREET VIRGINIA COURT MIDWAY DRIVE 75TH STREET 70 70 705 705 ELM STREET EVANS PLACE JANET AVENUE PLAINFIELD ROAD EAST BRANCH SAWMILL CREEK (SWSW) 700 700 695 695 690 SWSW0030 SWSW003 SWSW0032 SWSW0033 685 27500 28000 28500 29000 29500 30000 30500 3000 3500 32000 32500 33000 33500 34000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SAWMILL CREEK AT DES PLAINES RIVER SWSW0034 SWSW0035 SWSW0036 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 44P

ELEVATION IN FEET (NGVD 29) ROGER ROAD 69TH STREET 68TH STREET 725 725 720 720 67TH STREET LIMIT OF DETAILED STUDY EAST BRANCH SAWMILL CREEK (SWSW) 75 75 70 70 705 SWSW0037 700 34000 34500 35000 35500 36000 36500 37000 37500 38000 SWSW0038 SWSW0039 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SAWMILL CREEK AT DES PLAINES RIVERH 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 45P

CONFLUENCE WITH SAWMILL CREEK NORTHGATE DRIVE 690 690 685 685 CONFLUENCE OF WEST BRANCH SAWMILL CREEK WARDS CREEK (SWSW) ELEVATION IN FEET (NGVD 29) 680 680 675 675 670 670 665 665 660 SWSW00 655 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 9000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SAWMILL CREEK 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 46P

S FRONTAGE ROAD LIMIT OF DETAILED STUDY 705 705 700 700 WARDS CREEK (SWSW) ELEVATION IN FEET (NGVD 29) 695 695 690 690 685 685 680 680 675 SWSW002 670 9000 9500 20000 20500 2000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SAWMILL CREEK 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 47P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH SAWMILL CREEK 700 700 UNNAMED ROAD LEOMAR LANE WESTERN AVENUE INTERSTATE 55 695 695 690 690 685 685 680 680 CLARENDON HILLS ROAD 8ST STREET SAWMILL CREEK TRIBUTARY NO. (SWSW) 675 675 670 670 665 SWSW0027 660 8000 8500 9000 9500 20000 20500 2000 2500 22000 22500 23000 23500 24000 24500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE OF SAWMILL CREEK AT DES PLAINES RIVER SWSW0028 SWSW0029 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE DU PAGE COUNTY, IL 48P

ELEVATION IN FEET (NGVD 29) WILLIAM DRIVE 79TH STREET CONFLUENCE OF EAST BRANCH SAWMILL CREEK 700 700 SAWMILL CREEK TRIBUTARY NO. (SWSW) 695 695 690 690 685 680 24500 25000 25500 26000 26500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE OF SAWMILL CREEK AT DES PLAINES RIVER 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE DU PAGE COUNTY, IL 49P

ELEVATION IN FEET (NGVD 29) 9ST STREET LIMIT OF DETAILED STUDY 70 70 SAWMILL CREEK TRIBUTARY NO. 3 (DPDP) 705 705 700 700 695 DPDP0023 690 3000 3200 3400 3600 3800 DPDP0024 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 5P

00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 700 700 5TH AVENUE ROYAL ST. GEORGE AVENUE 695 695 690 690 OGDEN AVENUE ZAININGER AVENUE BURNING TREE LANE FOOTBRIDGE WEST STREET CRESS CREEK (WBCC) ELEVATION IN FEET (NGVD 29) 685 685 680 680 LIMIT OF DETAILED STUDY 675 675 670 670 665 WBCC000 WBCC0002 WBCC0003 WBCC0004 660 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DU PAGE RIVER WBCC0005 WBCC0006 WBCC0007 WBCC0008 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 50P

00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH WEST BRANCH DUPAGE RIVER MCDOWELL ROAD CONFLUENCE OF FERRY CREEK TRIBUTARY NO. FOREST RESERVE ROAD EAST BOUND TOLLWAY (I-88) 700 700 695 695 690 690 WEST BOUND TOLLWAY (I-88) FERRY ROAD PRIVATE ROAD THE 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR PROFILE TO BE SHOWN SEPARATELY FERRY CREEK (WBFE) 685 685 680 680 675 670 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBFE0006 WBFE0007 WBFE0008 WBFE0009 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBFE000 5P

75 75 PRIVATE ROAD FARM ROAD FARM ROAD 70 70 705 705 AURORA WAY RAILROAD BUTTERFIELD ROAD FERRY CREEK (WBFE) ELEVATION IN FEET (NGVD 29) 700 700 THE 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR PROFILE TO BE SHOWN SEPARATELY 695 695 690 690 685 685 680 WBFE00 WBFE002 WBFE003 WBFE004 675 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBFE005 WBFE006 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBFE007 52P

HOME AVENUE STATE ROUTE 59 PRIVATE BRIDGE AND WEIR 720 720 FERRY CREEK (WBFE) ELEVATION IN FEET (NGVD 29) 75 75 70 70 705 705 700 700 695 WBFE008 WBFE009 WBFE0020 690 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 WBFE002 WBFE0022 CULVERT WBFE0023 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBFE0024 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 53P

LIMIT OF DETAILED STUDY FERRY CREEK (WBFE) ELEVATION IN FEET (NGVD 29) 720 720 75 75 70 70 705 WBFE0025 700 8000 8500 9000 9500 20000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 54P

00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH FERRY CREEK RAYMOND ROAD 695 695 690 690 FERRY CREEK TRIBUTARY NO. (WBFE) 685 685 680 680 675 WBFE000 670 0 200 400 600 800 000 200 400 600 800 2000 2200 2400 2600 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH FERRY CREEK WBFE0002 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 55P

ELEVATION IN FEET (NGVD 29) 705 705 700 700 695 695 FERRY CREEK TRIBUTARY NO. (WBFE) 690 690 685 685 680 675 2600 2800 3000 3200 3400 3600 3800 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH FERRY CREEK 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 56P

ELEVATION IN FEET (NGVD 29) 705 700 695 MC DOWELL ROAD LIMIT OF DETAILED STUDY 705 700 695 FERRY CREEK TRIBUTARY NO. (WBFE) 690 685 680 675 WBFE0003 WBFE0004 3600 3800 4000 4200 4400 4600 4800 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 690 685 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH FERRY CREEK 57P

00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) COUNTY BOUNDARY FOOTBRIDGE PRIVATE DRIVE WASHINGTON STREET DIKE 655 655 650 650 87TH STREET THE 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR PROFILE TO BE SHOWN SEPARATELY UNNAMED CREEK (SOUTH OF FOXCROFT ROAD) (WBFX) 645 645 640 640 635 WBFX000 WBFX0002 630 0 250 500 750 000 250 500 750 2000 2250 2500 2750 3000 WBFX0003 STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY WBFX0004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 58P

ELEVATION IN FEET (NGVD 29) 660 660 655 655 650 650 645 THE 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR PROFILE TO BE SHOWN SEPARATELY LIMIT OF DETAILED STUDY 640 3000 3250 3500 3750 4000 WBFX0005 STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD UNNAMED CREEK (SOUTH OF FOXCROFT ROAD) (WBFX) 59P

ELEVATION IN FEET (NGVD 29) COUNTY BOUNDARY 700 700 COUNTY LINE ROAD DREW AVENUE 79TH STREET HAMILTON AVENUE 695 695 690 690 685 685 LIMIT OF DETAILED STUDY 79TH STREET DITCH (DPFC) 680 680 675 675 670 DPFC000 DPFC0002 DPFC0003 DPFC0004 DPFC0005 665 0 500 000 500 2000 2500 3000 3500 4000 DPFC0006 DPFC0007 DPFC0008 DPFC0009 STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY 500-YEAR FLOOD 00-YEAR FLOOD 500-YEAR FLOOD 0-YEAR FLOOD 6P

666 666 ELEVATION IN FEET (NGVD 29) 664 664 COUNTY BOUNDARY 662 662 660 660 658 658 656 656 STORM SEWER LIMIT OF DETAILED STUDY UNNAMED CREEK (SOUTH OF 87TH STREET) (WBFX) 654 654 652 652 650 648 5000 5200 5400 5600 5800 6000 6200 6400 6600 WBFX00 WBFX002 STREAM DISTANCE IN FEET ABOVE MOUTH 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 60P

00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER CONFLUENCE WITH WEST BRANCH DUPAGE RIVER IL PRAIRIE PATH CONFLUENCE OF KLEIN CREEK TRIBUTARY NO. 735 735 730 730 FARM ROAD KLEIN CREEK (WBKC) ELEVATION IN FEET (NGVD 29) 725 725 720 720 75 75 70 70 705 WBKC000 700 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBKC0002 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 6P

COUNTY FARM ROAD RAILROAD ST. CHARLES ROAD 755 755 750 750 NORTH AVENUE KUHN ROAD KLEIN CREEK (WBKC) ELEVATION IN FEET (NGVD 29) 745 745 740 740 735 735 730 730 725 WBKC0003 WBKC0004 WBKC0005 WBKC0006 720 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBKC0007 WBKC0008 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 62P

THUNDERBIRD TRAIL CONFLUENCE OF KLEIN CREEK TRIBUTARY NO. 2 (THUNDERBIRD TRAIL CREEK) 755 755 750 750 ILLINI DRIVE DAM "A" SPILLWAY NO. 3 KLEIN CREEK (WBKC) ELEVATION IN FEET (NGVD 29) 745 745 740 740 735 735 730 730 725 WBKC0009 WBKC000 720 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 9000 9500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBKC00 WBKC002 500-YEAR FLOOD 500-YEAR FLOOD 500-YEAR FLOOD 0-YEAR FLOOD 63P

765 765 760 760 DITCH CROSSING ELK TRAIL SPILLWAY NO. 2 755 755 750 750 DITCH CROSSING SPILLWAY NO. KLEIN CREEK (WBKC) ELEVATION IN FEET (NGVD 29) 745 745 740 740 735 735 730 730 725 WBKC003 CULVERT WBKC004 CULVERT 720 9500 20000 20500 2000 2500 22000 22500 23000 23500 24000 24500 25000 25500 26000 WBKC005 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBKC006 LIES ROAD GARY AVENUE 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBKC007 64P

CONFLUENCE OF KLEIN CREEK TRIBUTARY NO. 3 RAILROAD 770 770 KLEIN CREEK (WBKC) ELEVATION IN FEET (NGVD 29) 765 765 760 760 755 755 750 750 745 WBKC008 740 26000 26500 27000 27500 28000 28500 29000 29500 30000 30500 3000 3500 32000 32500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBKC009 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 65P

SCHMALE ROAD LIMIT OF DETAILED STUDY KLEIN CREEK (WBKC) ELEVATION IN FEET (NGVD 29) 770 770 765 765 760 WBKC0020 755 32500 33000 33500 34000 34500 35000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 66P

750 750 ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH KLEIN CREEK 745 745 COUNTY FARM ROAD 740 740 735 735 CENTER AVENUE 730 730 725 725 KLEIN CREEK TRIBUTARY NO. (WBKC) 720 720 75 75 70 705 0 500 000 500 2000 2500 3000 WBKC002 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH KLEIN CREEK 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 67P

785 ELEVATION IN FEET (NGVD 29) WEIR WEIR PLEASANT HILL ROAD LIMIT OF DETAILED STUDY 765 765 760 760 KLEIN CREEK TRIBUTARY NO. (WBKC) 755 755 750 750 745 WBKC0022 CULVERT CULVERT 740 3000 3500 4000 4500 5000 5500 6000 6500 WBKC0023 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH KLEIN CREEK 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 68P

775 775 ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH KLEIN CREEK 770 770 SEMINOLE LAKE THUNDERBIRD TRAIL BLACKHAWK DRIVE LIMIT OF DETAILED STUDY 765 765 760 760 755 755 750 750 KLEIN CREEK TRIBUTARY NO. 2 745 745 740 740 735 WBKC0024 WBKC0025 WBKC0026 WBKC0027 WBKC0028 WBKC0029 WBKC0030 730 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH KLEIN CREEK 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 69P

ELEVATION IN FEET (NGVD 29) 70 70 COUNTY BOUNDARY COUNTY LINE ROAD FIELDSTONE DRIVE 705 705 700 700 695 695 CULVERT 690 690 INTERNATIONAL HARVESTER ENTRANCE WEIR WEIR INTERNATIONAL STREET COMMERCE STREET CULVERTS UNNAMED ROAD UNNAMED ROAD PLAINFIELD ROAD DITCH (DPFC) 685 685 680 680 675 DPFC000 CULVERTS 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR PROFILE TO BE SHOWN SEPARATELY DPFC002 DPFC00 DPFC003 DPFC004 DPFC005 670-500 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 DPFC006 DPFC007 DPFC008 DPFC009 STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY DPFC0020 DPFC002 DPFC0022 DPFC0023 DPFC0024 DPFC0025 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 7P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH KLEIN CREEK GARY AVENUE OLD GARY AVENUE 84TH COURT LIMIT OF DETAILED STUDY 770 770 765 765 KLEIN CREEK TRIBUTARY NO. 3 (WBKC) 760 760 755 755 750 WBKC003 745 0 500 000 500 2000 2500 3000 3500 4000 WBKC0032 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH KLEIN CREEK WBKC0033 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 70P

00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 725 725 STATE ROUTE 59 JOLIET STREET 720 720 75 75 FOOTBRIDGE KRESS CREEK (WBKR) ELEVATION IN FEET (NGVD 29) 70 70 705 705 700 700 695 695 690 WBKR000 WBKR0002 WBKR0003 685 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER JOY ROAD WBKR0004 WBKR0005 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 7P

MAY STREET RAILROAD FOOTBRIDGE CONFLUENCE OF UNNAMED TRIBUTARY TO KRESS CREEK TOWN ROAD 730 730 KRESS CREEK (WBKR) ELEVATION IN FEET (NGVD 29) 725 725 720 720 75 75 70 70 705 WBKR0006 WBKR0007 WBKR0008 700 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBKR0009 WBKR000 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 72P

ROAD A RAILROAD 745 745 740 740 KRESS CREEK (WBKR) ELEVATION IN FEET (NGVD 29) 735 735 730 730 725 725 720 720 75 WBKR00 WBKR002 70 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 9000 9500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBKR003 WBKR004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 73P

FABYAN PARKWAY MCCHESNEY ROAD 755 755 750 750 FOOTBRIDGE ROOSEVELT ROAD RAILROAD KRESS CREEK (WBKR) ELEVATION IN FEET (NGVD 29) 745 745 740 740 735 735 730 730 725 WBKR005 WBKR006 720 9500 20000 20500 2000 2500 22000 22500 23000 23500 24000 24500 25000 25500 26000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBKR007 WBKR008 WBKR009 WBKR0020 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE UPSTREAM OF FOOTBRIDGE 74P

DOWNS DRIVE WESTERN DRIVE INDIAN BOUNDARY ROAD 755 755 750 750 RAILROAD SPUR INDUSTRIAL DRIVE KRESS CREEK (WBKR) ELEVATION IN FEET (NGVD 29) 745 745 740 740 735 735 730 730 725 WBKR002 WBKR0022 WBKR0023 WBKR0024 WBKR0025 WBKR0026 720 26000 26500 27000 27500 28000 28500 29000 29500 30000 30500 3000 3500 32000 32500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBKR0027 WBKR0028 WBKR0029 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD WBKR0030 *DATA NOT AVAILABLE 75P

HAWTHORNE LANE RAILROAD SPUR HARVESTER ROAD RAILROAD SPUR KRESS CREEK (WBKR) ELEVATION IN FEET (NGVD 29) 755 755 750 750 745 745 740 740 735 WBKR003 WBKR0032 730 32500 33000 33500 34000 34500 35000 35500 36000 36500 37000 37500 38000 38500 39000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBKR0033 WBKR0034 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD * DATA NOT AVAILABLE DOWNSTREAM OF APPROXIMATELY 37,500 FT ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 76P

UNNAMED DRIVE CROWN COURT POWIS ROAD LIMIT OF DETAILED STUDY 760 760 KRESS CREEK (WBKR) ELEVATION IN FEET (NGVD 29) 755 755 750 750 745 745 740 740 735 730 39000 39500 40000 40500 4000 4500 42000 42500 WBKR0035 WBKR0036 WBKR0037 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 77P

00-YEAR BACKWATER FROM KRESS CREEK ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH KRESS CREEK 750 750 ROOSEVELT ROAD PARKING LOT BRIDGE TOWN ROAD 745 745 740 740 THE 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR PROFILE TO BE SHOWN SEPARATELY 735 735 730 730 PRIVATE ROAD RAILROAD UNNAMED TRIBUTARY TO KRESS CREEK (WBKR) 725 725 720 720 75 WBKR0038 WBKR0039 WBKR0040 WBKR004 70 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH KRESS CREEK WBKR0042 WBKR0043 WBKR0044 WBKR0045 WBKR0046 WBKR0047 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 78P

ELEVATION IN FEET (NGVD 29) INDUSTRIAL DRIVE INDUSTRIAL DRIVE GENEVA ROAD RAILROAD RAILROAD RAILROAD LIMIT OF DETAILED STUDY 760 760 755 755 UNNAMED TRIBUTARY TO KRESS CREEK (WBKR) 750 750 745 745 740 WBKR0048 WBKR0049 WBKR0050 WBKR005 WBKR0052 CULVERT WBKR0053 735 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH KRESS CREEK WBKR0054 WBKR0055 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD * DATA NOT AVAILABLE UPSTREAM OF RAILROAD CULVERT 79P

ELEVATION IN FEET (NGVD 29) UNNAMED ROAD LIMIT OF PROFILE* PLAINFIELD ROAD DITCH (DPFC) 70 70 705 705 700 DPFC0026 CULVERT DPFC0027 DPFC0028 695 5000 5500 6000 6500 * PROFILE INFORMATION NOT AVAILABLE UPSTREAM OF THIS POINT STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 8P

00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) 75 CONFLUENCE WITH WEST BRANCH DUPAGE RIVER MORRIS COURT ROAD 70 70 705 705 700 700 695 695 PAMELA ROAD SPRING BROOK NO. (WBSP) 690 690 685 685 680 WBSP000 WBSP0002 675 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBSP0003 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 80P

ELEVATION IN FEET (NGVD 29) WINFIELD ROAD UNNAMED ROAD UNNAMED ROAD 720 720 75 75 70 70 SPRING BROOK NO. (WBSP) 705 705 700 700 695 WBSP0004 690 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBSP0005 WBSP0006 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 8P

ELEVATION IN FEET (NGVD 29) 725 725 720 720 75 75 70 70 705 ESSEX ROAD WBSP0007 WBSP0008 FOOTBRIDGE WBSP0009 700 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 9000 9500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBSP000 SEWAGE PLANT BRIDGE SEWAGE PLANT BRIDGE WBSP00 SEWAGE PLANT BRIDGE WBSP002 W. CREEKSIDE DRIVE WBSP003 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBSP004 SPRING BROOK NO. (WBSP) 82P

ELEVATION IN FEET (NGVD 29) 740 740 STONEBRIDGE TRAIL CREEKSIDE DRIVE FOOTBRIDGE 735 735 730 730 725 725 720 720 W. AURORA WAY S. GABLES BOULEVARD PRAIRIE PATH SPRING BROOK NO. (WBSP) 75 75 70 70 705 WBSP005 WBSP006 WBSP007 WBSP008 700 9500 20000 20500 2000 2500 22000 22500 23000 23500 24000 24500 25000 25500 26000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBSP009 WBSP0020 WBSP002 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBSP0022 83P

ELEVATION IN FEET (NGVD 29) WARRENVILLE ROAD HAWTHORNE LANE 735 735 730 730 725 725 LIMIT OF E. ELM STREET LIMIT OF DETAILED STUDY SPRING BROOK NO. (WBSP) 720 720 75 75 70 705 26000 26500 27000 27500 28000 28500 29000 29500 30000 30500 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBSP0023 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 84P

ELEVATION IN FEET (NGVD 29) COUNTY BOUNDARY PRIVATE DRIVE BAILEY ROAD 75TH STREET HOBSON ROAD 670 670 660 660 650 650 CONFLUENCE OF WEST BRANCH TRIBUTARY NO. 6 FOOTBRIDGE WEST BRANCH DUPAGE RIVER (WBWB) 640 640 630 630 620 WBWB000 WBWB0002 WBWB0003 60 000 2000 3000 4000 5000 6000 7000 8000 9000 20000 2000 22000 23000 24000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER WBWB0004 WBWB0005 WBWB0006 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 85P

ELEVATION IN FEET (NGVD 29) GARTNER ROAD HILLSIDE ROAD WASHINGTON STREET MAIN STREET WEBSTER STREET EAGLE STREET JEFFERSON AVENUE 690 690 680 680 670 670 WEST BRANCH DUPAGE RIVER (WBWB) 660 660 650 650 640 WBWB0007 WBWB0008 WBWB0009 WBWB000 630 24000 25000 26000 27000 28000 29000 30000 3000 32000 33000 34000 35000 36000 37000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER WBWB00 WBWB002 WBWB003 WBWB004 WBWB005 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBWB006 86P

ELEVATION IN FEET (NGVD 29) RAILROAD CONFLUENCE OF CRESS CREEK OGDEN AVENUE FAWELL DAM 70 70 700 700 690 690 680 680 LOWFLOW DAM CONFLUENCE OF FERRY CREEK WEST BRANCH DUPAGE RIVER (WBWB) 670 670 660 660 650 WBWB007 WBWB008 CULVERT WBWB009 640 37000 38000 39000 40000 4000 42000 43000 44000 45000 46000 47000 48000 49000 50000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER CULVERT WBWB0020 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 87P

ELEVATION IN FEET (NGVD 29) TOLLWAY (I-88) TOLLWAY (I-88) 70 70 700 700 690 690 WARRENVILLE ROAD FOOTBRIDGE LOW FLOW DAM ILLINOIS PRAIRE PATH STATE HIGHWAY 56 BUTTERFIELD ROAD CONFLUENCE OF SPRING BROOK NO. WEST BRANCH DUPAGE RIVER (WBWB) 680 680 670 670 660 WBWB002 WBWB0022 WBWB0023 WBWB0024 650 50000 5000 52000 53000 54000 55000 56000 57000 58000 59000 60000 6000 62000 63000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER WBWB0025 WBWB0026 WBWB0027 CULVERT WBWB0028 WBWB0029 WBWB0030 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 88P

ELEVATION IN FEET (NGVD 29) ACCESS ROAD WILLIAMS ROAD MACK ROAD CONFLUENCE OF KRESS CREEK 70 70 700 700 WEST BRANCH DUPAGE RIVER (WBWB) 690 690 680 680 670 WBWB003 WBWB0032 WBWB0033 WBWB0034 WBWB0035 660 63000 64000 65000 66000 67000 68000 69000 70000 7000 72000 73000 74000 75000 76000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER WBWB0036 WBWB0037 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 89P

700 700 ELEVATION IN FEET (NGVD 29) 695 695 690 690 685 685 680 680 675 675 670 670 665 665 660 COUNTY BOUNDARY COUNTY LINE ROAD DPFC0029 ELM STREET 655 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 DPFC0030 STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY GARFIELD AVENUE DPFC003 WOODEN FOOTBRIDGE WEIR GRANT AVENUE 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* CULVERT CONFLUENCE OF UNNAMED TRIBUTARY A *DATA NOT AVAILABLE DOWNSTREAM OF 7,066 FEET 63RD STREET DITCH (DPFC) 9P

ELEVATION IN FEET (NGVD 29) GARY'S MILL ROAD (ROOSEVELT ROAD) STATE ROUTE 38 720 720 70 70 CONFLUENCE OF WEST BRANCH TRIBUTARY NO. 5 WEST BRANCH DUPAGE RIVER (WBWB) 700 700 690 690 680 WBWB0038 WBWB0039 WBWB0040 WBWB004 WBWB0042 670 76000 77000 78000 79000 80000 8000 82000 83000 84000 85000 86000 87000 88000 89000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBWB0043 90P

ELEVATION IN FEET (NGVD 29) BEECHER AVENUE RAILROAD HIGHLAKE ROAD UNNAMED ROAD GENEVA ROAD 740 740 730 730 720 720 WEST BRANCH DUPAGE RIVER (WBWB) 70 70 700 700 690 WBWB0044 WBWB0045 WBWB0046 WBWB0047 WBWB0048 WBWB0049 680 89000 90000 9000 92000 93000 94000 95000 96000 97000 98000 99000 00000 0000 02000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER WBWB0050 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBWB005 9P

ELEVATION IN FEET (NGVD 29) CONFLUENCE OF KLEIN CREEK 740 740 730 730 720 720 ABANDONED RAILROAD CONFLUENCE OF WEST BRANCH TRIBUTARY NO. 3 CONFLUENCE OF WEST BRANCH TRIBUTARY NO. 4 RAILROAD WEST BRANCH DUPAGE RIVER (WBWB) 70 70 700 700 690 WBWB0052 WBWB0053 680 02000 03000 04000 05000 06000 07000 08000 09000 0000 000 2000 3000 4000 5000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER WBWB0054 WBWB0055 WBWB0056 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 92P

ELEVATION IN FEET (NGVD 29) NORTH AVENUE ST. CHARLES ROAD UNNAMED ROAD UNNAMED ROAD 740 740 730 730 WEST BRANCH DUPAGE RIVER (WBWB) 720 720 70 70 700 WBWB0057 WBWB0058 WBWB0059 WBWB0060 WBWB006 690 5000 6000 7000 8000 9000 20000 2000 22000 23000 24000 25000 26000 27000 28000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER WBWB0062 WBWB0063 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 93P

ELEVATION IN FEET (NGVD 29) ARMY TRAIL ROAD SCHICK ROAD RAILROAD PRIVATE BRIDGE 760 760 750 750 CONFLUENCE OF COUNTRY CREEK/ WEST BRANCH TRIBUTARY NO. 2 WEST BRANCH DUPAGE RIVER (WBWB) 740 740 730 730 720 WBWB0064 WBWB0065 WBWB0066 WBWB0067 70 28000 29000 30000 3000 32000 33000 34000 35000 36000 37000 38000 39000 40000 4000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER WBWB0068 WBWB0069 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 94P

ELEVATION IN FEET (NGVD 29) 780 770 770 760 760 COUNTY FARM ROAD WEST BRANCH DUPAGE RIVER (WBWB) 750 750 740 740 730 WBWB0070 WBWB007 720 4000 42000 43000 44000 45000 46000 47000 48000 49000 50000 5000 52000 53000 54000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER WBWB0072 WBWB0073 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 95P

ELEVATION IN FEET (NGVD 29) CONFLUENCE OF WEST BRANCH TRIBUTARY NO. ARLINGTON DRIVE U.S. ROUTE 20 FARM BRIDGE 800 800 790 790 780 780 RAILROAD COUNTY BOUNDARY WEST BRANCH DUPAGE RIVER (WBWB) 770 770 760 760 750 WBWB0074 WBWB0075 740 54000 55000 56000 57000 58000 59000 60000 6000 62000 63000 64000 65000 WBWB0076 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DUPAGE RIVER WBWB0077 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 96P

00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) FOREST PRESERVE ROAD LIMIT OF DETAILED STUDY 772 772 770 770 768 768 766 766 FOOTBRIDGE WEST BRANCH TRIBUTARY NO. (WBW) 764 764 762 762 760 WBW000 758 5800 6000 6200 6400 6600 6800 7000 7200 7400 7600 7800 8000 8200 8400 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 97P

ELEVATION IN FEET (NGVD 29) CLOVERDALE ROAD 774 774 772 772 770 770 768 768 GARY AVENUE LIMIT OF DETAILED STUDY WEST BRANCH TRIBUTARY NO. (WBW) 766 766 764 764 762 WBW0002 760 8400 8600 8800 9000 9200 9400 9600 9800 0000 0200 0400 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBW0003 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 98P

775 775 00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 770 770 765 765 760 760 755 755 750 750 STEARNS ROAD WEST BRANCH TRIBUTARY NO. 2 (COUNTRY CREEK) (WBW2) 745 745 740 740 735 WBW2000 730 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 99P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH GEORGE STREET RESERVOIR JEFFERSON AVENUE LIMIT OF DETAILED STUDY 665 665 660 660 ADDISON CREEK TRIBUTARY NO. (DPAC) 655 655 650 650 645 640 69000 69500 70000 70500 7000 7500 72000 DPAC000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 02P

725 725 ELEVATION IN FEET (NGVD 29) 720 720 MADISON STREET 75 75 70 70 705 705 700 700 LANE COURT STATE ROUTE 83/ ROBERT KINGERY HIGHWAY LAKE HINSDALE DRIVE LIMIT OF DETAILED STUDY 63RD STREET DITCH (DPFC) 695 695 690 690 685 DPFC0032 DPFC0033 680 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 3000 DPFC0034 STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY DPFC0035 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* *DATA NOT AVAILABLE DOWNSTREAM OF 7,066 FEET 20P

ELEVATION IN FEET (NGVD 29) 790 790 FRANCINE DRIVE 785 785 780 780 THE 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR PROFILE TO BE SHOWN SEPARATELY BROOKSIDE DRIVE WEST COUNTRY DRIVE FOOTBRIDGE 775 775 770 770 FOOTBRIDGE DEVON AVENUE LIMIT OF DETAILED STUDY WEST BRANCH TRIBUTARY NO. 2 (COUNTRY CREEK) (WBW2) 765 765 760 760 755 WBW20002 WBW20003 WBW20004 750 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBW20005 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 200P

750 750 00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) 745 745 740 740 735 735 730 730 725 725 720 720 75 75 70 CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBW3000 705 0 400 800 200 600 2000 2400 2800 3200 3600 4000 4400 4800 5200 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER PRINCE CROSSING ROAD WBW30002 RAILROAD WBW30003 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBW30004 WEST BRANCH TRIBUTARY NO. 3 (WBW3) 20P

ELEVATION IN FEET (NGVD 29) 755 755 750 750 745 745 740 740 FOOTBRIDGE 735 735 WAYNEWOOD DRIVE LIMIT OF DETAILED STUDY WEST BRANCH TRIBUTARY NO. 3 (WBW3) 730 730 725 725 720 WBW30005 75 5200 5600 6000 6400 6800 7200 7600 8000 8400 WBW30006 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBW30007 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 202P

00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 745 745 RAILROAD 740 740 735 735 730 730 725 725 NORTH AVENUE WEST BRANCH TRIBUTARY NO. 4 (WBW4) 720 720 75 75 70 WBW4000 WBW40002 705 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBW40003 WBW40004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 203P

ELEVATION IN FEET (NGVD 29) ST. CHARLES ROAD TIMBER LANE LIMIT OF DETAILED STUDY 745 745 740 740 WEST BRANCH TRIBUTARY NO. 4 (WBW4) 735 735 730 730 725 WBW40005 720 6500 7000 7500 8000 8500 9000 9500 0000 0500 WBW40006 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 204P

ELEVATION IN FEET (NGVD 29) 00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER CONFLUENCE WITH WEST BRANCH DUPAGE RIVER LESTER STREET BOLLES AVENUE DONALD AVENUE 725 725 720 720 75 75 CHICAGO AND NORTH WESTERN RAILROAD LIMIT OF DETAILED STUDY WEST BRANCH TRIBUTARY NO. 5 (WBW5) 70 70 705 705 700 WBW5000 695 0 250 500 750 000 250 500 750 2000 WBW50002 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBW50003 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 205P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH WEST BRANCH DUPAGE RIVER HOBSON MILL DRIVE (WEST) 00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER 670 670 665 665 660 660 655 655 WEST BRANCH TRIBUTARY NO. 6 (WBW6) 650 650 645 645 640 635 0 00 200 300 400 500 600 700 800 900 000 00 200 300 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBW6000 206P

ELEVATION IN FEET (NGVD 29) HOBSON MILL DRIVE (EAST) 685 685 680 680 675 675 WEST BRANCH TRIBUTARY NO. 6 (WBW6) 670 670 665 665 660 655 300 400 500 600 700 800 900 2000 200 2200 2300 2400 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 207P

ELEVATION IN FEET (NGVD 29) UNNAMED ROAD LIMIT OF DETAILED STUDY 690 690 685 685 WEST BRANCH TRIBUTARY NO. 6 (WBW6) 680 680 675 675 670 665 2400 2500 2600 2700 2800 WBW60002 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 208P

00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 675 675 670 670 665 665 660 660 655 655 UNNAMED ROAD WEST BRANCH TRIBUTARY NO. 7 (WBW7) 650 650 645 645 640 635 0 00 200 300 400 500 600 700 800 900 000 00 200 300 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 209P

720 720 LIMIT OF DETAILED STUDY STATE ROUTE 83/ ROBERT KINGERY HIGHWAY 78 THE 50- AND 00-YEAR 78 ARE TOO CLOSE TO BE SHOWN SEPARATELY ANN STREET FOOTBRIDGE PRIVATE DRIVE PRIVATE DRIVE PRIVATE DRIVE PRIVATE DRIVE PRIVATE DRIVE PRIVATE DRIVE FOOTBRIDGE HARRIS AVENUE 76 76 74 74 FLAGG CREEK (DPFC) ELEVATION IN FEET (NGVD 29) 72 72 70 70 708 708 706 706 704 DPFC0036 DPFC0037 702 48600 48800 49000 49200 49400 49600 49800 50000 50200 50400 50600 DPFC0038 PRIVATE DRIVE PRIVATE DRIVE PRIVATE DRIVE PRIVATE DRIVE STREAM DISTANCE IN FEET ABOVE MOUTH PRIVATE DRIVE PRIVATE DRIVE DPFC0039 PRIVATE DRIVE LIMIT OF DETAILED STUDY 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 2P

ELEVATION IN FEET (NGVD 29) UNNAMED ROAD OXFORD LANE 685 685 680 680 675 675 WEST BRANCH TRIBUTARY NO. 7 (WBW7) 670 670 665 665 660 WBW7000 655 300 400 500 600 700 800 900 2000 200 2200 2300 2400 2500 2600 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 20P

ELEVATION IN FEET (NGVD 29) 685 685 680 680 675 675 670 670 665 665 660 655 2600 2700 2800 2900 3000 300 3200 3300 3400 3500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBW70002 LIMIT OF DETAILED STUDY 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE WEST BRANCH TRIBUTARY NO. 7 (WBW7) 2P

00-YEAR BACKWATER FROM WEST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH WEST BRANCH DUPAGE RIVER FARM BRIDGE SUMMIT DRIVE PARK STREET WINFIELD ROAD CHURCH STREET PRIVATE DRIVE MANCHESTER ROAD 720 720 75 75 70 70 WINFIELD CREEK (WBWF) 705 705 700 700 695 WBWF000 WBWF0002 WBWF0003 WBWF0004 WBWF0005 WBWF0006 WBWF0007 WBWF0008 WBWF0009 690 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBWF000 WBWF00 WBWF002 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBWF003 22P

ELEVATION IN FEET (NGVD 29) ROOSEVELT ROAD SCHAFFNER ROAD HIGH SCHOOL ROAD ROAD TO APARTMENTS 730 730 725 725 720 720 WINFIELD CREEK (WBWF) 75 75 70 70 705 WBWF004 WBWF005 WBWF006 WBWF007 WBWF008 700 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBWF009 WBWF0020 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 23P

ELEVATION IN FEET (NGVD 29) W. ROOSEVELT ROAD S. BEVERLY STREET FOOTBRIDGE FOOTBRIDGE WOODLAWN STREET W. CHILDS STREET PRIVATE ROAD 730 730 725 725 DORCHESTER AVENUE WINFIELD CREEK (WBWF) 720 720 75 75 70 WBWF002 WBWF0022 WBWF0023 705 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 9000 9500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBWF0024 WBWF0025 WBWF0026 WBWF0027 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 24P

ELEVATION IN FEET (NGVD 29) W. MANCHESTER ROAD RAILROAD W. UNION AVENUE W. LINCOLN AVENUE ILLINOIS PRAIRIE PATH GARY AVENUE ELLIS AVENUE EXTENDED LOW FLOW DAM LOW FLOW DAM FOOTBRIDGE 740 740 735 735 730 730 CULVERT WINFIELD CREEK (WBWF) 725 725 720 720 75 WBWF0028 WBWF0029 WBWF0030 WBWF003 70 9500 20000 20500 2000 2500 22000 22500 23000 23500 24000 24500 25000 25500 26000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBWF0032 WBWF0033 WBWF0034 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD WBWF0035 25P

ELEVATION IN FEET (NGVD 29) 750 750 WHEATON COURT MAIN STREET CONFLUENCE OF WINFIELD CREEK TRIBUTARY DRIVE TO ST. MARKS SCHOOL E. COLE AVENUE 745 745 740 740 735 735 730 730 PADDOCK COURT GENEVA ROAD WINFIELD CREEK (WBWF) 725 725 720 720 75 WBWF0036 WBWF0037 WBWF0038 WBWF0039 70 26000 26500 27000 27500 28000 28500 29000 29500 30000 30500 3000 3500 32000 32500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBWF0040 WBWF004 WBWF0042 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 26P

FARM ROAD LIMIT OF DETAILED STUDY WINFIELD CREEK (WBWF) ELEVATION IN FEET (NGVD 29) 750 750 745 745 740 740 735 735 730 WBWF0043 WBWF0044 WBWF0045 725 32500 33000 33500 34000 34500 35000 35500 WBWF0046 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 27P

685 685 ELEVATION IN FEET (NGVD 29) 680 680 CONFLUENCE WITH WEST BRANCH DUPAGE RIVER SWALLOW ROAD CHAT COURT VERDIN LANE 675 675 CULVERTS 670 670 665 665 660 660 TERRANCE DRIVE WINDING CREEK (WBWG) 655 655 CULVERTS 650 650 645 640 0 400 800 200 600 2000 2400 2800 3200 3600 4000 4400 4800 5200 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER WBWG000 WBWG0002 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 28P

ELEVATION IN FEET (NGVD 29) MODAFF ROAD LIMIT OF DETAILED STUDY 690 690 685 685 680 680 WINDING CREEK (WBWG) 675 675 670 670 665 WBWG0003 CULVERTS WBWG0004 660 5200 5600 6000 6400 6800 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 29P

ELEVATION IN FEET (NGVD 29) COUNTY BOUNDARY COUNTY LINE ROAD CHARLESTON ROAD NORTH CHARLESTON ROAD SOUTH LIMIT OF DETAILED STUDY 680 680 675 675 59TH STREET DITCH (DPFC) 670 670 665 665 660 DPFC0040 655 0 250 500 750 000 250 500 DPFC004 DPFC0042 DPFC0043 STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 22P

685 685 ELEVATION IN FEET (NGVD 29) LIMIT OF DETAILED STUDY 680 680 PRIVATE DRIVE PRIVATE DRIVE THORNDALE AVENUE 675 675 670 670 665 665 660 660 THOMAS DRIVE RAILROAD FAIRWAY DRIVE LIMIT OF DETAILED STUDY SOUTH UNNAMED CREEK (DPWL) 655 655 650 650 645 DPWL000 DPWL0002 640 3335 3385 3435 3485 3535 3585 3635 3685 3735 3785 3835 3885 3935 3985 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER DPWL0003 DPWL0004 DPWL0005 DPWL0006 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD DPWL0007 23P

ELEVATION IN FEET (NGVD 29) LIMIT OF DETAILED STUDY LIMIT OF DETAILED STUDY 670 670 665 665 660 660 NORTH UNNAMED CREEK (DPWL) 655 655 650 650 645 DPWL0008 DPWL0009 640 33000 33500 34000 34500 35000 35500 36000 36500 DPWL000 DPWL00 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 24P

ELEVATION IN FEET (NGVD 29) COUNTY BOUNDARY 87TH STREET 665 665 660 660 SPRING BROOK NO. 2 (DUSG) 655 655 650 650 645 DUSG000 640 7000 7500 8000 8500 9000 9500 20000 20500 2000 2500 22000 22500 23000 23500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER DUSG0002 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 25P

ELEVATION IN FEET (NGVD 29) NAPERVILLE ROAD 670 670 SPRING BROOK NO. 2 (DUSG) 665 665 660 660 655 DUSG0003 650 23500 24000 24500 25000 25500 26000 26500 27000 27500 28000 28500 29000 29500 30000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER DUSG0004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 26P

ELEVATION IN FEET (NGVD 29) 83RD STREET 83RD STREET BOOK ROAD BOOK ROAD 680 680 675 675 SPRING BROOK NO. 2 (DUSG) 670 670 665 665 660 DUSG0005 655 30000 30500 3000 3500 32000 32500 33000 33500 34000 34500 35000 35500 36000 36500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER DUSG0006 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 27P

ELEVATION IN FEET (NGVD 29) 75TH STREET 690 690 685 685 RICKERT DRIVE OAKTON LANE DUSG0009 WEIR SPRING BROOK/ COUNTRYSIDE LAKE SPRING BROOK NO. 2 (DUSG) 680 680 CULVERT 675 675 670 CULVERT DUSG0007 665 36500 37000 37500 38000 38500 39000 39500 40000 40500 4000 4500 42000 42500 43000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER DUSG0008 DUSG000 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 28P

ELEVATION IN FEET (NGVD 29) SPRING BROOK/ COUNTRYSIDE LAKE SEQUOIA ROAD OSWEGO ROAD LAKE OSBORNE 690 690 WHISPERING HILLS DRIVE OGDEN AVENUE LIMIT OF DETAILED STUDY SPRING BROOK NO. 2 (DUSG) 685 685 680 680 675 CULVERT DUSG00 DUSG002 CULVERT DUSG003 670 43000 43500 44000 44500 45000 45500 46000 46500 47000 47500 48000 48500 49000 CULVERT STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER DUSG004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 29P

ELEVATION IN FEET (NGVD 29) CONFLUENCE AT GEORGE STREET RESERVOIR 685 685 680 680 675 675 SPILLWAY CONFLUENCE OF ADDISON CREEK TRIBUTARY NO. 3 YORK ROAD 670 670 665 665 CHURCH ROAD LIMIT OF DETAILED STUDY 690 ADDISON CREEK TRIBUTARY NO. 2 (DPAC) 660 660 655 655 650 DPAC00 DPAC002 645 68500 69500 70500 7500 72500 73500 74500 75500 76500 DPAC003 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 03P

740 740 ELEVATION IN FEET (NGVD 29) LIMIT OF DETAILED STUDY TREATMENT PLANT ROAD 735 735 WAYNE AVENUE JILL COURT LESLIE LANE ARMITAGE AVENUE GLEN ELLYN ROAD 730 730 725 725 720 720 75 75 HIGHLAND AVENUE WINTHROP AVENUE CONFLUENCE OF ARMITAGE FORK FULLERTON AVENUE ARMITAGE DITCH (EBAR) 70 70 705 705 700 EBAR000 EBAR0002 EBAR0003 EBAR0004 EBAR0005 695 200 700 2200 2700 3200 3700 4200 4700 5200 5700 6200 6700 7200 7700 EBAR0006 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBAR0007 EBAR0008 EBAR0009 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD EBAR000 30P

765 765 ELEVATION IN FEET (NGVD 29) 760 760 ARDMORE AVENUE LINCOLN AVENUE 755 755 750 750 POLO CLUB ROAD PLACID AVENUE 745 745 740 740 LIMIT OF DETAILED STUDY ARMITAGE DITCH (EBAR) 735 735 730 730 725 EBAR00 720 7700 8200 8700 9200 9700 0200 0700 200 700 EBAR002 EBAR003 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBAR004 EBAR005 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 3P

765 765 ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH ARMITAGE DITCH 760 760 755 755 750 750 745 745 740 740 LIMIT OF DETAILED STUDY ARMITAGE FORK (EBAR) 735 735 730 730 725 720 0 250 500 750 000 250 500 750 2000 2250 2500 EBAR006 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH ARMITAGE DITCH EBAR007 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 32P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH EAST BRANCH DUPAGE RIVER SEWAGE DISPOSAL ROAD STATE HIGHWAY 53 680 680 670 670 660 660 CRABTREE CREEK (EBCR) 650 650 640 640 630 EBCR000 620 0 200 400 600 800 000 200 400 600 800 2000 2200 2400 2600 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 33P

ELEVATION IN FEET (NGVD 29) WESTVIEW LANE 70 70 700 700 690 690 680 680 CRABTREE CREEK (EBCR) 670 670 660 660 650 EBCR0002 640 2600 2800 3000 3200 3400 3600 3800 4000 4200 4400 4600 4800 5000 5200 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBCR0003 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 34P

WOODRIDGE DRIVE LIMIT OF DETAILED STUDY CRABTREE CREEK (EBCR) ELEVATION IN FEET (NGVD 29) 720 720 70 70 700 700 690 690 680 670 5200 5400 5600 5800 6000 6200 EBCR0004 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 35P

ELEVATION IN FEET (NGVD 29) COUNTY BOUNDARY CONFLUENCE OF CRABTREE CREEK 660 660 655 655 650 650 645 645 75TH STREET CONFLUENCE OF EAST BRANCH TRIBUTARY NO. 7 EAST BRANCH DUPAGE RIVER (EBEB) 640 640 635 635 630 625 33000 34000 35000 36000 37000 38000 39000 40000 4000 42000 43000 44000 45000 46000 EBEB000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER EBEB0002 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 36P

ELEVATION IN FEET (NGVD 29) HOBSON ROAD & CONFLUENCE WITH PRENTISS CREEK WEIR CONFLUENCE OF ST. PROCOPIUS CREEK SUMMERHILL DRIVE 670 670 665 665 660 660 655 655 FOUR LAKES AVENUE MAPLE AVENUE SHORT STREET CONFLUENCE OF ROTT CREEK EAST BRANCH DUPAGE RIVER (EBEB) 650 650 645 645 640 EBEB0003 EBEB0004 635 46000 47000 48000 49000 50000 5000 52000 53000 54000 55000 56000 57000 58000 59000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER EBEB0005 EBEB0006 EBEB0007 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD EBEB0008 EBEB0009 37P

ELEVATION IN FEET (NGVD 29) 685 685 680 680 675 675 RAILROAD BURLINGTON AVENUE U.S. HIGHWAY 34 (OGDEN AVENUE) CONFLUENCE OF EAST BRANCH TRIBUTARY NO. 3 CONFLUENCE OF ST. JOSEPH CREEK LACEY AVENUE MIDDLETON AVENUE EAST - WEST TOLLWAY (I-88) WARRENVILLE ROAD 670 670 665 665 ARBORETUM ROAD CONFLUENCE OF EASH BRANCH TRIBUTARY NO. 5 ARBORETUM ROAD STATE ROUTE 53 EAST BRANCH DUPAGE RIVER (EBEB) 660 660 655 655 650 EBEB000 EBEB00 EBEB002 EBEB003 EBEB004 EBEB005 EBEB006 EBEB007 645 59000 60000 6000 62000 63000 64000 65000 66000 67000 68000 69000 70000 7000 72000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER EBEB008 EBEB009 EBEB0020 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 38P

ELEVATION IN FEET (NGVD 29) CONFLUENCE OF LACEY CREEK BUTTERFIELD ROAD (STATE ROUTE 56) 685 685 680 680 675 675 670 670 CONFLUENCE OF EAST BRANCH TRIBUTARY NO. 4 TREATMENT PLANT ROAD CONFLUENCE OF UNNAMED STREAM NORTH OF 22ND STREET EAST BRANCH DUPAGE RIVER (EBEB) 665 665 660 660 655 EBEB002 EBEB0022 EBEB0023 EBEB0024 EBEB0025 650 72000 73000 74000 75000 76000 77000 78000 79000 80000 8000 82000 83000 84000 85000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER EBEB0026 EBEB0027 EBEB0028 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 39P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH ADDISON CREEK TRIBUTARY NO. 2 00-YEAR BACKWATER FROM ADDISON CREEK NO 2 APARTMENT DRIVEWAY APARTMENT DRIVEWAY GEORGE STREET DENNIS DRIVE DENNIS DRIVE S. YORK ROAD FOREST VIEW ROAD 685 685 680 680 675 675 670 670 CONFLUENCE OF TRIBUTARY A ADDISON CREEK TRIBUTARY NO. 3 (DPAC) 665 665 CULVERTS 660 660 655 DPAC004 DPAC005 650 69000 69500 70000 70500 7000 7500 72000 72500 73000 73500 74000 74500 75000 75500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER DPAC006 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD *DATA NOT AVAILABLE FROM 2,047 FEET UPSTREAM OF FOREST VIEW ROAD TO 4,099 FEET UPSTREAM OF FOREST 04P

ELEVATION IN FEET (NGVD 29) ROOSEVELT ROAD STATE ROUTE 53 690 690 685 685 680 680 EAST BRANCH DUPAGE RIVER (EBEB) 675 675 670 670 665 EBEB0029 EBEB0030 EBEB003 EBEB0032 660 85000 86000 87000 88000 89000 90000 9000 92000 93000 94000 95000 96000 97000 98000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER EBEB0033 EBEB0034 EBEB0035 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD EBEB0036 40P

ELEVATION IN FEET (NGVD 29) 75 75 ILLINOIS PRAIRIE PATH (MAIN STEM) 70 70 HILL AVENUE CRESCENT BOULEVARD ST. CHARLES ROAD 705 705 700 700 695 695 690 690 ABANDONED RAILROAD CONFLUENCE OF EAST BRANCH TRIBUTARY NO. 2 CONFLUENCE OF EAST BRANCH TRIBUTARY NO. NORTH AVENUE EAST BRANCH DUPAGE RIVER (EBEB) 685 685 680 680 675 EBEB0037 EBBE0038 EBEB0039 670 98000 99000 00000 0000 02000 03000 04000 05000 06000 07000 08000 09000 0000 000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER EBEB0040 EBEB004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 4P

ELEVATION IN FEET (NGVD 29) CONFLUENCE OF ARMITAGE DITCH RAILROAD 75 75 TOP OF RAIL = 739.0 70 70 705 705 700 700 CONFLUENCE OF SWIFT MEADOWS TRIBUTARY EAST BRANCH DUPAGE RIVER (EBEB) 695 695 690 690 685 EBEB0042 EBEB0043 680 000 2000 3000 4000 5000 6000 7000 8000 9000 20000 2000 22000 EBEB0044 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER EBEB0045 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 42P

ELEVATION IN FEET (NGVD 29) ARMY TRAIL ROAD LIMIT OF DETAILED STUDY 720 720 75 75 EAST BRANCH DUPAGE RIVER (EBEB) 70 70 705 705 700 EBEB0046 695 22000 23000 24000 25000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 43P

725 00-YEAR BACKWATER FROM EAST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) 720 75 CONFLUENCE WITH EAST BRANCH DUPAGE RIVER UNNAMED ROAD SWIFT ROAD 70 70 705 705 700 700 EAST BRANCH TRIBUTARY NO. (EBE) 695 695 690 690 685 680 0 200 400 600 800 000 200 400 600 800 2000 2200 2400 2600 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBE000 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 44P

ELEVATION IN FEET (NGVD 29) NORTH AVENUE LIMIT OF DETAILED STUDY 720 720 75 75 70 70 EAST BRANCH TRIBUTARY NO. (EBE) 705 705 700 700 695 690 2600 2800 3000 3200 3400 3600 3800 4000 4200 4400 4600 4800 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBE0002 EBE0003 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 45P

730 730 ELEVATION IN FEET (NGVD 29) 725 725 720 720 75 75 70 70 705 CULVERTS 705 700 700 695 695 690 CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBE2000 EBE200 EASTERN AVENUE EBE2002 EBE2003 CULVERT EBE2004 GLENRISE AVENUE EBE2005 EBE2006 PRIVATE CULVERT EBE2007 EBE2008 685 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER PRIVATE CULVERT CULVERTS EBE2009 PARK BOULEVARD EBE200 EBE20 EBE202 FOREST AVENUE EBE203 EBE204 CULVERTS MAIN STREET EBE205 EBE206 EBE207 EBE208 EBE209 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD LIMIT OF DETAILED STUDY EAST BRANCH TRIBUTARY NO. 2 (EBE2) 46P

00-YEAR BACKWATER FROM EAST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH EAST BRANCH DUPAGE RIVER TWIN CULVERTS THROUGH LEVEE 695 695 RIVER DRIVE PARKING LOT CROSSING SWARTZ AVENUE 690 690 685 685 680 680 675 675 PRIVATE DRIVE PRIVATE DRIVE DEVON AVENUE EAST BRANCH TRIBUTARY NO. 3 (EBEB) 670 670 665 665 660 CULVERT EBEB0047 EBEB0048 655 0 200 400 600 800 000 200 400 600 800 2000 2200 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBEB0049 EBEB0050 EBEB005 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 47P

ELEVATION IN FEET (NGVD 29) WINCHESTER AVENUE MIDDLETON AVENUE LIMIT OF DETAILED STUDY 75 75 70 70 705 705 700 700 EAST BRANCH TRIBUTARY NO. 3 (EBEB) 695 695 690 690 685 EBEB0052 680 2200 2400 2600 2800 3000 3200 3400 EBEB0053 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 48P

00-YEAR BACKWATER FROM EAST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH EAST BRANCH DUPAGE RIVER SUNNYBROOK ROAD GLEN CREST DRIVE BEMIS ROAD 705 705 700 700 695 695 690 690 EAST BRANCH TRIBUTARY NO. 4 (EBGL) 685 685 680 680 675 EBGL000 670 0 500 000 500 2000 2500 3000 EBGL0002 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 49P

ELEVATION IN FEET (NGVD 29) ARTHUR COURT LIMIT OF DETAILED STUDY 690 690 685 685 CULVERT 680 680 ADDISON CREEK TRIBUTARY NO. 3 (DPAC) 675 675 670 670 665 DPAC007 660 75500 76000 76500 77000 77500 78000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD *DATA NOT AVAILABLE FROM 2,047 FEET UPSTREAM OF FOREST VIEW ROAD TO 4,099 FEET UPSTREAM OF FOREST VIEW ROAD 05P

740 740 ELEVATION IN FEET (NGVD 29) 735 735 STATE ROUTE 53 (BRYANT AVENUE) FOOTBRIDGE 22ND STREET 730 730 725 725 720 720 SHEFFIELD ROAD 75 75 LIMIT OF DETAILED STUDY EAST BRANCH TRIBUTARY NO. 4 (EBGL) 70 70 705 705 700 EBGL0003 EBGL0004 EBGL0005 695 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 EBGL0006 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DU PAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 50P

705 705 00-YEAR BACKWATER FROM EAST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 700 700 DAM UNNAMED ROAD UNNAMED ROAD DAM 695 695 690 690 685 685 680 680 ARBORETUM ROAD UNNAMED ROAD UNNAMED ROAD LEASK LANE LIMIT OF FLOODING CULVERT EAST BRANCH TRIBUTARY NO. 5 (EBWI) 675 675 670 670 665 EBWI000 EBWI0002 660 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBWI0003 EBWI0004 EBWI0005 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 5P

ELEVATION IN FEET (NGVD 29) 725 725 LIMIT OF PRIVATE ROAD PRIVATE ROAD REGENCY WOODS DRIVE 720 720 75 75 70 70 705 705 NORTH ARBORETUM CIRCLE ROBINWOOD LANE EAST BRANCH TRIBUTARY NO. 5 (EBWI) 700 700 695 695 690 EBWI0006 EBWI0007 EBWI0008 685 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 EBWI0009 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBWI000 EBWI00 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 52P

ELEVATION IN FEET (NGVD 29) 735 735 THE 50-YEAR FLOOD PROFILE IS TOO CLOSE 730 TO THE 00-YEAR PROFILE TO BE 730 SHOWN SEPARATELY LIMIT OF DETAILED STUDY EAST BRANCH TRIBUTARY NO. 5 (EBWI) 725 725 720 720 75 EBWI002 70 500 2000 2500 3000 3500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 53P

75 75 ELEVATION IN FEET (NGVD 29) LIMIT OF DETAILED STUDY 70 70 705 705 700 700 CULVERT 695 695 690 690 MILL BRIDGE LANE CULVERT ST. PROCOPIUS CREEK (EBE6) 685 685 680 680 675 670 6800 7000 7200 7400 7600 7800 8000 8200 8400 8600 8800 9000 9200 9400 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBE6000 EBE60002 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 54P

720 720 ELEVATION IN FEET (NGVD 29) PRIVATE ROAD 75 75 70 70 THE 50- AND 500-YEAR ARE TOO CLOSE TO BE SHOWN SEPARATELY COLLEGE ROAD LIMIT OF DETAILED STUDY 705 705 700 700 ST. PROCOPIUS CREEK (EBE6) 695 695 690 690 685 EBE60003 680 9400 9600 9800 0000 0200 0400 EBE60004 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 55P

00-YEAR BACKWATER FROM EAST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) 700 700 CONFLUENCE WITH EAST BRANCH DUPAGE RIVER GREENE ROAD 690 690 680 680 670 670 660 660 DRIVEWAY TO DERBY DRIVE FOOTBRIDGE EAST BRANCH TRIBUTARY NO. 7 (EBE7) 650 650 640 640 630 EBE7000 620 0 400 800 200 600 2000 2400 2800 3200 3600 4000 4400 4800 5200 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBE70002 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD EBE70003 * DATA NOT AVAILABLE 56P

ELEVATION IN FEET (NGVD 29) PRIVATE ROAD TO 75TH STREET FOOTBRIDGE MURRAY DRIVE PALOMINO DRIVE LIMIT OF DETAILED STUDY 730 730 720 720 70 70 700 700 EAST BRANCH TRIBUTARY NO. 7 (EBE7) 690 690 680 680 670 EBE70004 EBE70005 660 5200 5600 6000 6400 6800 7200 7600 8000 EBE70006 EBE70007 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD * DATA NOT AVAILABLE 57P

ELEVATION IN FEET (NGVD 29) 690 690 685 685 680 680 675 675 670 670 665 665 500-YEAR FLOOD 660 CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 00-YEAR BACKWATER FROM EAST BRANCH DUPAGE RIVER EBLA000 EBLA0002 655 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER PRIVATE ROAD EBLA0003 PRIVATE ROAD EBLA0004 PRIVATE ROAD EBLA0005 PRIVATE ROAD EBLA0006 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD LACEY CREEK (EBLA) 58P

ELEVATION IN FEET (NGVD 29) 700 700 695 695 690 690 685 685 680 680 675 675 500-YEAR FLOOD 670 FINLEY ROAD EBLA0007 EBLA0008 DOWNERS DRIVE EBLA0009 665 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBLA000 VENARD DRIVE EBLA00 SARATOGA AVENUE EBLA002 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD BARNESWOOD DRIVE EBLA003 LACEY CREEK (EBLA) 59P

ELEVATION IN FEET (NGVD 29) LIMIT OF DETAILED STUDY ORCHARD AVENUE GARDEN AVENUE RAILROAD RAILROAD N. YORK ROAD AUTO PARTS ROAD 670 670 665 665 660 660 IRVING PARK BOULEVARD MASON STREET BENSENVILLE DITCH (DPBD) 655 655 650 650 645 DPBD000 DPBD0002 DPBD0003 640 43500 44000 44500 45000 45500 46000 46500 47000 47500 48000 48500 49000 DPBD0004 DPBD0005 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER DPBD0006 DPBD0007 DPBD0008 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* *DATA NOT AVAILABLE 06P

ELEVATION IN FEET (NGVD 29) 75 75 70 70 705 705 700 700 695 695 690 690 685 685 500-YEAR FLOOD 680 HIGHLAND AVENUE EBLA004 EBLA005 675 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 WILLIAMS COLLEGE PRIVATE ROAD STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBLA006 EBLA007 EBLA008 EBLA009 FAIRVIEW AVENUE LIMIT OF DETAILED STUDY 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD LACEY CREEK (EBLA) 60P

FLOODING CONTROLLED BY EAST BRANCH DUPAGE RIVER 00-YEAR BACKWATER FROM EAST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) 665 HOBSON ROAD CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 660 660 655 655 665 PRENTISS CREEK (EBPR) 650 650 645 645 640 635 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER CULVERTS 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 6P

690 690 ELEVATION IN FEET (NGVD 29) 685 685 STATE ROUTE 53 680 680 675 675 670 670 665 665 PRENTISS CREEK (EBPR) 660 660 655 655 650 CULVERT EBPR000 645 6000 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 62P

725 725 ELEVATION IN FEET (NGVD 29) 720 720 HOBSON ROAD PRIVATE DRIVE 75 75 70 70 705 705 700 700 PUFFER ROAD PRENTISS CREEK (EBPR) 695 695 690 690 685 EBPR0002 EBPR0003 680 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBPR0004 EBPR0005 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 63P

ELEVATION IN FEET (NGVD 29) 745 745 WOODWARE AVENUE PRENTISS DRIVE 740 740 735 735 730 730 725 725 SPRINGSIDE AVENUE DUNHAM ROAD PRENTISS CREEK (EBPR) 720 720 75 75 70 EBPR0006 EBPR0007 EBPR0008 705 7500 8000 8500 9000 9500 20000 20500 2000 2500 22000 22500 23000 23500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBPR0009 EBPR000 EBPR00 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 64P

ELEVATION IN FEET (NGVD 29) 70 70 700 700 690 690 680 680 670 670 660 660 650 650 500-YEAR FLOOD 640 CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 00-YEAR BACKWATER FROM EAST BRANCH DUPAGE RIVER EBRC000 PRIVATE DRIVE CULVERT EBRC0002 VARSITY DRIVE CULVERT EBRC0003 630 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER YACKLEY AVENUE EBRC0004 YACKLEY AVENUE EBRC0005 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD RAILROAD EBRC0006 ROTT CREEK (EBRC) 65P

ELEVATION IN FEET (NGVD 29) 730 730 720 720 70 70 700 700 690 690 680 680 500-YEAR FLOOD 670 EBRC0007 EBRC0008 BURLINGTON AVENUE BEAU BIEN ROAD FOOTBRIDGE 660 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER KELLER STREET BURLINGTON AVENUE EBRC0009 FENDER AVENUE OGDEN AVENUE EBRC000 EBRC00 FENDER AVENUE 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD ROTT CREEK (EBRC) 66P

ELEVATION IN FEET (NGVD 29) 740 740 730 730 CULVERT 720 720 70 70 500-YEAR FLOOD 700 FOOT BRIDGE EBRC002 EBRC003 EBRC004 OLD TAVERN ROAD EBRC005 EBRC006 EBRC007 690 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 EBRC008 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EAST-WEST TOLLWAY (I-88) 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD ROTT CREEK (EBRC) 67P

ELEVATION IN FEET (NGVD 29) 740 740 730 730 720 720 70 70 500-YEAR FLOOD 700 WARRENVILLE ROAD PRIVATE ROAD NAPERVILLE ROAD LIMIT OF DETAILED STUDY 690 8000 8500 9000 9500 20000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD ROTT CREEK (EBRC) 68P

690 690 00-YEAR BACKWATER FROM EAST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 685 685 DUMOULIN AVENUE LINCOLN AVENUE (STATE HIGHWAY 53) MAIN STREET CONFLUENCE OF TRIBUTARY (A) CENTER STREET 680 680 675 675 670 670 665 665 OGDEN AVENUE (U.S. HIGHWAY 34) RAILROAD CULVERT ST. JOSEPH CREEK (EBSJ) 660 660 655 655 650 EBSJ000 EBSJ0002 EBSJ0003 EBSJ0004 EBSJ0005 EBSJ0006 645 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBSJ0007 EBSJ0008 EBSJ0009 EBSJ000 EBSJ00 EBSJ002 EBSJ003 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 69P

ELEVATION IN FEET (NGVD 29) CHURCH ROAD LIMIT OF DETAILED STUDY 670 670 665 665 660 660 BENSENVILLE DITCH (DPBD) 655 655 650 650 645 DPBD0009 DPBD000 640 49000 49500 50000 50500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH DES PLAINES RIVER 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* *DATA NOT AVAILABLE 07P

ELEVATION IN FEET (NGVD 29) 695 695 690 690 685 685 680 680 675 675 670 670 665 665 660 EBSJ004 CONFLUENCE OF TRIBUTARY 2 (B) EBSJ005 EBSJ006 EBSJ007 EBSJ008 655 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER WALNUT AVENUE EBSJ009 EBSJ0020 EBSJ002 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD CURTISS STREET EBSJ0022 ST. JOSEPH CREEK (EBSJ) 70P

ELEVATION IN FEET (NGVD 29) BELMONT ROAD LEE AVENUE PRIVATE DRIVE 700 700 695 695 690 690 ST. JOSEPH CREEK (EBSJ) 685 685 680 680 675 EBSJ0023 EBSJ0024 EBSJ0025 670 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 9000 9500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBSJ0026 EBSJ0027 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 7P

ELEVATION IN FEET (NGVD 29) JACQUELINE DRIVE BROOKBANK ROAD LIMIT OF DETAILED STUDY 705 705 700 700 695 695 690 690 ST. JOSEPH CREEK (EBSJ) 685 685 680 680 675 EBSJ0028 EBSJ0029 670 9500 20000 20500 2000 2500 22000 22500 EBSJ0030 EBSJ003 EBSJ0032 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 72P

ELEVATION IN FEET (NGVD 29) LIMIT OF DETAILED STUDY 725 725 MACKIE AVENUE 720 720 75 75 70 70 CULVERT CONFLUENCE OF NORTH BRANCH ST. JOSEPH CREEK MAPLE AVENUE CULVERT BLODGETT AVENUE GRAND AVENUE HILL STREET 705 705 55TH STREET CULVERT CULVERT GRAND AVENUE FAIRVIEW AVENUE DEERPATH ROAD ST. JOSEPH CREEK (EBSJ) 700 700 695 695 690 EBSJ0035 EBSJ0036 EBSJ0037 685 26000 26500 27000 27500 28000 28500 29000 29500 30000 30500 3000 3500 32000 32500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBSJ0038 BERM CONFLUENCE OF SOUTH BRANCH ST. JOSEPH CREEK EBSJ0039 EBSJ0040 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD EBSJ004 73P

ELEVATION IN FEET (NGVD 29) CUMNOR ROAD KING ARTHUR COURT CROSSING EASY ACRES GOLF COURSE CULVERT 735 735 730 730 725 725 720 720 CULVERT 57TH STREET/ WILLIAMS STREET JAMES DRIVE CONFLUENCE OF ST. JOSPEH CREEK TRIBUTARY 59TH STREET WILLIAM STREET ST. JOSEPH CREEK (EBSJ) 75 75 70 70 705 EBSJ0042 CULVERT EBSJ0043 EBSJ0044 700 32500 33000 33500 34000 34500 35000 35500 36000 36500 37000 37500 38000 38500 39000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBSJ0045 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 74P

ELEVATION IN FEET (NGVD 29) 6ST STREET 63RD STREET LIMIT OF DETAILED STUDY 740 740 735 735 ST. JOSEPH CREEK (EBSJ) 730 730 725 725 720 EBSJ0046 75 38000 38500 39000 39500 40000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 75P

700 700 00-YEAR BACKWATER FROM EAST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH ST. JOSEPH CREEK 695 695 CENTER STREET MIDDLETON AVENUE FOOTBRIDGE FOOTBRIDGE BUCKLEY AVENUE 690 690 685 685 680 680 675 675 WARRENVILLE ROAD TRIBUTARY (A) (EBSJ) 670 670 665 665 660 EBSJ0047 EBSJ0048 EBSJ0049 EBSJ0050 EBSJ005 EBSJ0052 655 0 200 400 600 800 000 200 400 600 800 2000 2200 2400 2600 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH ST. JOSEPH CREEK EBSJ0053 EBSJ0054 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD EBSJ0055 76P

720 720 ELEVATION IN FEET (NGVD 29) 75 75 70 70 THE 50- AND 500-YEAR PROFILES ARE TOO CLOSE TO THE 00-YEAR ELEVATIONS TO BE SHOWN SEPARATELY 705 705 700 700 TRIBUTARY (A) (EBSJ) 695 695 690 690 685 EBSJ0056 680 2600 2800 3000 3200 3400 3600 3800 4000 4200 4400 4600 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH ST. JOSEPH CREEK EBSJ0057 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 77P

ELEVATION IN FEET (NGVD 29) 730 730 THE 50- AND 500-YEAR PROFILES ARE TOO CLOSE TO THE 00-YEAR ELEVATIONS TO BE SHOWN SEPARATELY LIMIT OF DETAILED STUDY 725 725 720 720 TRIBUTARY (A) (EBSJ) 75 75 70 70 705 700 4500 4700 4900 500 5300 5500 EBSJ0058 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH ST. JOSEPH CREEK 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 78P

705 705 00-YEAR BACKWATER FROM ST. JOSEPH CREEK ELEVATION IN FEET (NGVD 29) 700 700 CONFLUENCE WITH ST. JOSEPH CREEK RAILROAD 695 695 690 690 685 685 680 680 FOOTBRIDGE LIMIT OF DETAILED STUDY TRIBUTARY 2 (B) (EBSJ) 675 675 670 670 665 EBSJ0059 EBSJ0060 660 0 200 400 600 800 000 200 400 600 800 2000 2200 2400 2600 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH ST. JOSEPH CREEK EBSJ006 EBSJ0062 EBSJ0063 EBSJ0064 EBSJ0065 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 79P

ELEVATION IN FEET (NGVD 29) COUNTY BOUNDARY 600 600 595 595 590 590 585 585 CONFLUENCE OF SAWMILL CREEK CONFLUENCE OF SAWMILL CREEK TRIBUTARY NO. 3 DES PLAINES RIVER (DPDP) 580 580 575 575 570 DPDP000 DPDP0002 565 32000 33000 34000 35000 36000 37000 38000 39000 40000 4000 42000 43000 44000 45000 DPDP0003 STREAM DISTANCE IN FEET ABOVE MOUTH DPDP0004 DPDP0005 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 08P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH ST. JOSEPH CREEK RAILROAD 730 730 725 725 720 720 75 75 CULVERT DOUGLAS ROAD CULVERT ROGER STREET AUSTIN STREET FAIRVIEW AVENUE WILCOX AVENUE THE 50-YEAR FLOOD PROFILE IS TOO CLOSE TO THE 00-YEAR ELEVATION TO BE SHOWN SEPARATELY 70 70 FLORENCE AVENUE CUMNOR ROAD LIMIT OF DETAILED STUDY NORTH BRANCH ST. JOSEPH CREEK (EBSJ) 705 705 700 700 695 EBSJ0066 CONCRETE VERTICAL DROP INTO CULVERT UNDER RAILROAD EBSJ0067 EBSJ0068 690 0 500 000 500 2000 2500 3000 3500 4000 4500 EBSJ0069 EBSJ0070 EBSJ007 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH ST. JOSEPH CREEK EBSJ0072 EBSJ0073 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 80P

00-YEAR BACKWATER FROM ST. JOSEPH CREEK ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH ST. JOSEPH CREEK 735 735 FAIRMOUNT AVENUE LYMAN AVENUE WASHINGTON STREET 730 730 725 725 720 720 THE 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR ELEVATION TO BE SHOWN SEPARATELY 75 75 WEBSTER STREET SOUTH BRANCH ST. JOSEPH CREEK (EBSJ) 70 70 705 705 700 EBSJ0074 EBSJ0075 EBSJ0076 EBSJ0077 EBSJ0078 EBSJ0079 695 0 500 000 500 2000 2500 3000 3500 4000 EBSJ0080 EBSJ008 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH ST. JOSEPH CREEK EBSJ0082 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 8P

ELEVATION IN FEET (NGVD 29) MAIN STREET PRIVATE DRIVE PRIVATE DRIVE PRIVATE DRIVE PRIVATE DRIVE PRIVATE DRIVE CARPENTER STREET BROOKBANK AVENUE THE 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR ELEVATION TO BE SHOWN SEPARATELY 59TH STREET MIDDAUGH ROAD 750 750 745 745 740 740 LIMIT OF DETAILED STUDY SOUTH BRANCH ST. JOSEPH CREEK (EBSJ) 735 735 730 730 725 EBSJ0083 EBSJ0084 EBSJ0085 EBSJ0086 EBSJ0087 EBSJ0088 EBSJ0089 720 4000 4500 5000 5500 6000 6500 7000 7500 8000 EBSJ0090 EBSJ009 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH ST. JOSEPH CREEK EBSJ0092 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 82P

ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH ST. JOSEPH CREEK 59TH STREET 60TH STREET 6ST STREET LIMIT OF DETAILED STUDY 735 735 730 730 CULVERT ST. JOSEPH CREEK TRIBUTARY (EBSJ) 725 725 720 720 75 EBSJ0093 70 0 500 000 500 2000 2500 3000 3500 EBSJ0094 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH ST. JOSEPH CREEK 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 83P

00-YEAR BACKWATER FROM EAST BRANCH DUPAGE RIVER ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH EAST BRANCH DUPAGE RIVER 70 70 705 705 700 700 THE 50-YEAR FLOOD PROFILE IS TO CLOSE TO THE 00-YEAR PROFILE TO BE SHOWN SEPARATELY 695 695 690 690 FINLEY ROAD LIMIT OF DETAILED STUDY UNNAMED STREAM NORTH OF 22ND STREET (EBTS) 685 685 680 680 675 EBTS000 EBTS0002 EBTS0003 670 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 EBTS0004 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH EAST BRANCH DUPAGE RIVER EBTS0005 EBTS0006 EBTS0007 EBTS0008 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 84P

795 795 ELEVATION IN FEET (NGVD 29) LIMIT OF DETAILED STUDY 790 790 MUNGER ROAD 785 785 780 780 775 775 770 770 BREWSTER CREEK (FRBC) 765 765 760 760 755 FRBC000 750 2000 2500 22000 22500 23000 23500 24000 24500 25000 25500 26000 26500 27000 27500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DU PAGE RIVER FRBC0002 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 85P

ELEVATION IN FEET (NGVD 29) STATE ROUTE 59 HIGH LEVEL BRIDGE LIMIT OF DETAILED STUDY 790 790 785 785 BREWSTER CREEK (FRBC) 780 780 775 775 770 765 27500 28000 28500 29000 29500 30000 FRBC0003 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH WEST BRANCH DU PAGE RIVER 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 86P

COUNTY BOUNDARY HONEY HILL DRIVE LIMIT OF DETAILED STUDY 750 750 NORTON CREEK (FRNC) ELEVATION IN FEET (NGVD 29) 745 745 740 740 735 735 730 730 725 FRNC000 FRNC0002 FRNC0003 720 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY FRNC0004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD FRNC0005 87P

ELEVATION IN FEET (NGVD 29) COUNTY BOUNDARY HONEY HILL ROAD ARMY TRAIL ROAD BILLY BURNS ROAD RAILROAD 755 755 750 750 745 745 740 740 POWIS ROAD LIMIT OF DETAILED STUDY NORTON CREEK TRIBUTARY (FRNC) 735 735 730 730 725 FRNC0006 FRNC0007 FRNC0008 720 0 000 2000 3000 4000 5000 6000 7000 8000 FRNC0009 FRNC000 FRNC00 FRNC002 STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 88P

ELEVATION IN FEET (NGVD 29) COUNTY BOUNDARY KAUTZ ROAD 675 675 670 670 WAUBANSEE CREEK (FRWA) 665 665 660 660 655 FRWA000 FRWA0002 FRWA0003 650 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY FRWA0004 FRWA0005 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE FRWA0006 89P

ELEVATION IN FEET (NGVD 29) 600 600 595 595 590 590 585 585 580 580 575 575 570 DPDP0006 DPDP0007 565 45000 46000 47000 48000 49000 50000 5000 52000 53000 54000 55000 56000 57000 DPDP0008 STREAM DISTANCE IN FEET ABOVE MOUTH DPDP0009 DPDP000 COUNTY BOUNDARY 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD DES PLAINES RIVER (DPDP) 09P

ELEVATION IN FEET (NGVD 29) EOLA ROAD LIMIT OF DETAILED STUDY 680 680 675 675 WAUBANSEE CREEK (FRWA) 670 670 665 665 660 FRWA0007 FRWA0008 655 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 FRWA0009 STREAM DISTANCE IN FEET ABOVE COUNTY BOUNDARY 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD *DATA NOT AVAILABLE 90P

680 680 ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH SALT CREEK 675 675 SPRING ROAD 670 670 THE 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR PROFILE TO BE SHOWN SEPARATELY 665 665 660 660 655 655 BRONSWOOD CEMETARY TRIBUTARY (SCBW) 650 650 645 645 640 SCBW000 SCBW0002 635 0 200 400 600 800 000 200 400 600 800 2000 2200 2400 2600 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCBW0003 SCBW0004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 9P

ELEVATION IN FEET (NGVD 29) NORTHERN CEMETARY BRIDGE 690 690 THE 50-YEAR PROFILE IS TOO CLOSE TO THE 00-YEAR PROFILE TO BE SHOWN SEPARATELY MIDDLE CEMETARY BRIDGE SOUTHERN CEMETARY BRIDGE 685 685 680 680 BRONSWOOD CEMETARY TRIBUTARY (SCBW) 675 675 670 670 665 SCBW0005 SCBW0006 SCBW0007 SCBW0008 660 2600 2800 3000 3200 3400 3600 3800 4000 4200 4400 4600 4800 5000 5200 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCBW0009 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 92P

ELEVATION IN FEET (NGVD 29) 70 70 705 705 700 700 695 695 690 690 685 685 680 680 675 SCBW000 DAM CULVERT SCBW00 ADAMS STREET SCBW002 CORPORATE LIMITS DAM SCBW003 CULVERT 670 5200 5400 5600 5800 6000 6200 6400 6600 6800 7000 7200 7400 7600 7800 PRIVATE DRIVE STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCBW004 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD STATE ROUTE 83/ LIMIT OF ROBERT KINGERY HIGHWAY LIMIT OF DETAILED STUDY SCBW005 BRONSWOOD CEMETARY TRIBUTARY (SCBW) 93P

ELEVATION IN FEET (NGVD 29) LIMIT OF DETAILED STUDY 689 689 688 688 687 687 686 686 685 685 PIERCE ROAD LIMIT OF DETAILED STUDY DEVON AVENUE TRIBUTARY (SCDA) 684 684 683 683 682 68 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 SCDA000 STREAM DISTANCE IN FEET ABOVE SALT CREEK SCDA0002 SCDA0003 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 94P

ELEVATION IN FEET (NGVD 29) 675 675 670 670 665 665 660 660 655 655 650 650 645 645 640 CONFLUENCE WITH SALT CREEK SCGC500 MCDONALDS SERVICE ROAD STONE WEIR SCGC5003 RONALD LANE SCGC5006 STONE WEIR LAKE FRED SCGC500 JORIE BOULEVARD SCGC50 GABION WEIR SCGC502 SCGC504 SCGC505 635 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 GABION WEIR STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCGC507 SCGC508 SCGC509 SCGC5020 ROUTE 83 BRIARWOOD CENTRAL ROAD CONCRETE WEIR CONFLUENCE OF MAYS LAKE TRIBUTARY CONFLUENCE OF BRIARWOOD DITCH 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* SCGC5030 *DATA NOT AVAILABLE GINGER CREEK (SCGC) 95P

700 700 ELEVATION IN FEET (NGVD 29) 695 695 690 690 685 685 680 680 675 675 670 670 665 665 660 SCGC503 SCGC5032 SCGC5033 REGENT DRIVE SCGC5035 SHEET PILE WEIR SCGC5036 SCGC5037 SCGC5038 SCGC5039 GABION WEIR SCGC5040 SCGC504 MIDWEST ROAD CULVERT SCGC5049 655 6500 7000 7500 8000 8500 9000 9500 0000 0500 000 500 2000 2500 3000 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCGC5050 SCGC5046 CONFLUENCE OF MIDWEST CLUB TRIBUTARY SCGC5067 SCGC5068 BAYBROOK LANE SCGC5053 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* CONFLUENCE OF LOMBARD TRIBUTARY *DATA NOT AVAILABLE GINGER CREEK (SCGC) 96P

BAYBROOK LANE CONFLUENCE OF HERITAGE OAKS TRIBUTARY MYERS ROAD DROP BOX LIMIT OF DETAILED STUDY GINGER CREEK (SCGC) ELEVATION IN FEET (NGVD 29) 700 700 695 695 690 690 685 685 680 SCGC5047 675 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 SCGC505 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH SALT CREEK SCGC5045 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* *DATA NOT AVAILABLE 97P

690 690 ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH GINGER CREEK 685 685 KINGSTON DR LIMIT OF DETAILED STUDY 680 680 675 675 670 670 665 665 BRIARWOOD DITCH (SCGC) 660 660 655 655 650 SCGC5043 SCGC5069 SCGC5073 645 0 500 000 500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH GINGER CREEK 500-YEAR FLOOD 00-YEAR FLOOD 50-YEAR FLOOD 0-YEAR FLOOD 98P

720 ELEVATION IN FEET (NGVD 29) CONFLUENCE WITH GINGER CREEK 00-YEAR BACKWATER FROM GINGER CREEK 705 700 700 695 695 75 70 HERITAGE OAKS TRIBUTARY 690 690 685 685 680 675 0 200 400 600 800 SCGC5044 STREAM DISTANCE IN FEET ABOVE CONFLUENCE WITH GINGER CREEK 500-YEAR FLOOD* 00-YEAR FLOOD 50-YEAR FLOOD* 0-YEAR FLOOD* *DATA NOT AVAILABLE 99P