CDM. City of Jacksonville Master Stormwater Management Plan (MSMP) Update. December 2008 Update. Agenda. 1. Data Collection. 2.

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1 City of Jacksonville Master Stormwater Management Plan (MSMP) Update December 2008 Update CDM Agenda 1. Data Collection 1. GIS/LiDAR 2. Survey 2. Water Quantity 1. SWMM Modeling 2. FEMA 3. Water Quality 1. County wide Pollutant Loading 4. Outreach 1

GIS/LiDAR 2. Survey 2. Water Quantity 1. SWMM Modeling 2.

2 GIS/LiDAR COJ has partnered with FDEM Vendor still has a few items to address to finalize data set Pending final approval of data set will work with the City of Jacksonville to make 2 foot contours available on COJ.net Survey We are nearly complete with all of the field survey with only Jullington Creek basin remaining To date we ve collected 186 Cross Sections 226 Structures (Culverts, Bridges, etc.) Julington Creek basin surveying scheduled to be completed by December 29 th which will complete most of the field survey work with the exception of a few ad hoc items Final projected tally includes: 230 Cross Sections 275 Structures (Culverts, Bridges, etc.) 2

net Survey We are nearly complete with all of the field survey with only Jullington Creek basin remaining To date we ve collected 186 Cross Sections 226 Structures

3 Water Quantity Update Currently there are 57 Sub-basins, grouped in 11 major basins New systems include: Seaton Creek (Thomas) East Branch Magnolia Gardens Currently there are more than 2,600 model nodes Modeling Tasks Model development includes the following activities: Model Conversion Vertical Datum Conversion Additional data collection Incorporation of new survey to update models Field Verification Model Review 3

Modeling Tasks Model development includes the following activities: Model Conversion Vertical Datum

4 Water Quantity Update Sub-basins are currently in one of three phases: Complete. Model is complete and is under review. Ongoing. Model is currently being developed. Not Started. Model will be started when survey data becomes available. Model results can change during the mapping task, therefore results should not be final until maps are completed. Water Quantity Schedule by Sub-basin November

Model will be started when survey data becomes available.

5 Model Verification during Tropical Storm Fay Data collected for Tropical Storm Fay (August 2008) has provided an ideal opportunity to collect field data CDM collected information to verify models against observed high water marks. Model Verification during Tropical Storm Fay CDM collected rainfall and tide information from several agencies Storm surge accounted for most of the flooding complaints Wind damage was minimal 5

6 Storm Fay High Water Marks CDM collected a total of 57 high water marks throughout the City Selected 38 locations were surveyed by COJ surveyors CDM assisted the City to manage the emergency Upcoming Model Verification Stag e ( ft) Measured Time (hr) Simulated Verification runs will include tail-water boundary conditions, and rainfall time series to replicate Storm Fay. Model results will be compared with high water marks collected in the field Pablo Creek Model Verification 6

5 Measured 0 200 400 600 800 Time (hr) Simulated Verification runs will include tail-water boundary conditions, and rainfall time

7 Mapping CDM has proposed a methodology that accounts for topographic and hydraulic conditions of our area. CDM met In June and October with the independent reviewer to discuss the mapping methodology CDM will submit preliminary maps for Cecil field and Strawberry Creek for review in December 2008 FEMA technical advisor has approved the proposed floodway methodology Activities included in the mapping task Conversion of model results to spatial files that display the flood zones Generation of FEMA databases that include structures, stream centerlines, transportation features, survey, and flood elevations Generation of a floodway to protect the channel storage Preparation of tables that summarize the model results by sub-basin 7

December 2008 FEMA technical advisor has approved the proposed floodway methodology Activities included in the mapping task Conversion of model results to spatial files that display

8 Mapping Strict requirements from FEMA regarding new studies have impacted the schedule of the mapping task, including: Supplemental Cross Sections Meandering streams Revision of old model cross sections Conduit length revision Estimated Mapping Schedule November

Cross Sections Meandering streams Revision of old model cross

9 Cecil Field Model Schematic Six sub-basins included: Sal Taylor Creek Rowell Creek Caldwell Branch Yellow Water St Mary s Ortega River The Updated FEMA Flood Zones are more accurate Better Topography Additional Survey of hydraulic structures Upgraded Models Dynamic evaluation Strawberry Creek 9

Updated FEMA Flood Zones are more accurate Better Topography Additional

10 Residents might be re-classified to new Flood Zones Increased understanding of flooding hazards Insurers can improve their policy coverage Water Quality Watershed Management Model (WMM) developed for COJ based on GIS coverages Land use (2004) Best Management Practices (BMPs) Septic tanks Other local or regional data Rainfall Streamflow Runoff and baseflow concentrations 10

(WMM) developed for COJ based on GIS coverages Land use (2004) Best Management Practices

11 Example Preliminary WMM Results (Total Nitrogen and Flow) Basin WMM TN (mg/l) 1 PLSM TN (mg/l) 2 WMM Flow (in/yr) 1 USGS Flow (in/yr) 3 Dunn Creek Ortega River Arlington River Julington Creek Notes: 1 Based on preliminary WMM results as of 2/25/ Based on PLSM provided to COJ for review. 3 USGS Ortega River Gage # : March February 2007 Example Preliminary WMM Results Flow 11

36 --- --- Julington Creek 1.28 0.88 --- --- Notes: 1 Based on preliminary WMM results as of 2/25/2008.

12 Example Preliminary WMM Results Total N Outreach Public Outreach Components Website with information on Map Modernization, schedule, and public meetings Regular updates provided to the LSJR Technical Advisory Committee Regular updates to the SSPAC Regular updates to CPAC Public meetings to present preliminary modeling and mapping information 12

provided to the LSJR Technical Advisory Committee Regular updates to the SSPAC Regular

13 Outreach Our Outreach message has focused on the benefits of Map Modernization Reduce the number of homes classified in the SFHA Reduce flood insurance rates by improving Jacksonville s Community Rating Score Provide needed information to guide future development and growth management Implementing alternatives will reduce loads to Lower St. Johns River Future Work Alternatives evaluation for each sub-basing with goals of improving water quantity and quality Develop CIP based on CDM s ranking matrix that has been developed for this project Publish new flood maps Complete QA/QC of LiDAR and provide access to public 13

alternatives will reduce loads to Lower St.

14 City of Jacksonville Master Stormwater Management Plan (MSMP) Update December 2008 Update CDM 14

15 Special Topics FEMA related activities Map revisions Independent QA/QC for modeling Floodway analysis Effective discharges Special Topics Bridge/Culvert modeling Permitted stormwater ponds 500 yr/24 hr design storm 15

Effective discharges Special Topics Bridge/Culvert

Fort Dodge Stormwater Master Planning. Prepared By: Ralph C. Stark, Jr., P.E., C.F.M. Joel N. Krause, P.E., C.F.M.

Fort Dodge Stormwater Master Planning Prepared By: Ralph C. Stark, Jr., P.E., C.F.M. Joel N. Krause, P.E., C.F.M. Project Location Project Background Flooding History Localized flooding and storm sewer