5.4.4 FLOOD. This section provides a profile and vulnerability assessment for the flood hazard. HAZARD PROFILE

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1 5.4.4 FLOOD This section provides a profile and vulnerability assessment for the flood hazard. HAZARD PROFILE This section provides profile information including description, location, extent, previous occurrences and losses and the probability of future occurrences. Description Floods are one of the most common natural hazards in the U.S. They can develop slowly over a period of days or develop quickly, with disastrous effects that can be local (impacting a neighborhood or community) or regional (affecting entire river basins, coastlines and multiple counties or states) (Federal Emergency Management Agency [FEMA], 2010). Most communities in the U.S. have experienced some kind of flooding, after spring rains, heavy thunderstorms, coastal storms, or winter snow thaws (George Washington University, 2001). Floods are the most frequent and costly natural hazards in New York State in terms of human hardship and economic loss, particularly to communities that lie within flood prone areas or flood plains of a major water source. As defined in the NYS HMP, flooding is a general and temporary condition of partial or complete inundation on normally dry land from the following: Riverine flooding, including overflow from a river channel, flash floods, alluvial fan floods, dambreak floods and ice jam floods; Local drainage or high groundwater levels; Fluctuating lake levels; Coastal flooding; Coastal erosion (NYS HMP 2011) Unusual and rapid accumulation or runoff of surface waters from any source; Mudflows (or mudslides); Collapse or subsidence of land along the shore of a lake or similar body of water caused by erosion, waves or currents of water exceeding anticipated cyclical levels that result in a flood as defined above (Floodsmart.gov, 2012); Sea Level Rise; or Climate Change (USEPA, 2012). A floodplain is defined as the land adjoining the channel of a river, stream, ocean, lake, or other watercourse or water body that becomes inundated with water during a flood. Most often, floodplains are referred to as 100-year floodplains. A 100-year floodplain is not the flood that will occur once every 100 years, rather it is the flood that has a one-percent chance of being equaled or exceeded each year. Thus, the 100-year flood could occur more than once in a relatively short period of time. With this term being misleading, FEMA has properly defined it as the one-percent annual chance flood. This one percent annual chance flood is now the standard used by most Federal and State agencies and by the National Flood Insurance Program (NFIP) (FEMA, One hundred-year floodplains (or 1% annual chance floodplain) can be described as a bag of 100 marbles, with 99 clear marbles and one black marble. Every time a marble is pulled out from the bag, and it is the black marble, it represents a 100-year flood event. The marble is then placed back into the bag and shaken up again before another marble is drawn. It is possible that the black marble can be picked one out of two or three times in a row, demonstrating that a 100-year flood event could occur several times in a row (Interagency Floodplain Management Review Committee, 1994). DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

2 2003). Figure depicts the flood hazard area, the flood fringe, and the floodway areas of a floodplain. Figure Floodplain Source: NJDEP, Date Unknown Many floods fall into three categories: riverine, coastal and shallow (FEMA, 2005). Other types of floods may include ice-jam floods, alluvial fan floods, dam failure floods, and floods associated with local drainage or high groundwater (as indicated in the previous flood definition). For the purpose of this HMP and as deemed appropriate by the Town, riverine/flash, dam failure and ice jam flooding are the main flood types of concern for the Planning Area. These types of flood are further discussed below. Riverine/Flash Floods Riverine floods are the most common flood type and occur along a channel, and include overbank and flash flooding. Channels are defined, ground features that carry water through and out of a watershed. They may be called rivers, creeks, streams or ditches. When a channel receives too much water, the excess water flows over its banks and inundates low-lying areas (FEMA, 2005; FEMA, 2008). Flash floods are a rapid and extreme flow of high water into a normally dry area, or a rapid water level rise in a stream or creek above a predetermined flood level, beginning within six hours of the causative event (e.g., intense rainfall, dam failure, ice jam). However, the actual time threshold may vary in different parts of the country. Ongoing flooding can intensify to flash flooding in cases where intense rainfall results in a rapid surge of rising flood waters (NWS, 2009). Ice-Jam Floods An ice jam is an accumulation of ice that acts as a natural dam and restricts flow of a body of water. Ice jams occur when warm temperatures and heavy rains cause rapid snow melt. The melting snow, combined with the heavy rain, causes frozen rivers to swell. The rising water breaks the ice layers into large chunks, which float downstream and often pile up near narrow passages and obstructions (bridges and dams). Ice jams may build up to a thickness great enough to raise the water level and cause flooding (NESEC, Date Unknown; FEMA, 2008). There are two different types of ice jams: freeze-up and breakup. Freeze-up jams occur when floating ice may slow or stop due to a change in water slope as it reaches an obstruction to movement. Breakup jams occur during periods of thaw, generally in late winter and early spring. The ice cover breakup is usually associated with a rapid increase in runoff and corresponding river discharge due to a heavy rainfall, snowmelt or warmer temperatures (USACE, 2002). DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

3 Dam Failure Floods A dam is an artificial barrier that has the ability to impound water, wastewater, or any liquid-borne material for the purpose of storage or control of water (FEMA, 2010). Dams are man-made structures built across a stream or river that impound water and reduce the flow downstream (FEMA, 2003). They are built for the purpose of power production, agriculture, water supply, recreation, and flood protection. Dam failure is any malfunction or abnormality outside of the design that adversely affect a dam s primary function of impounding water (FEMA, 2011). Dams can fail for one or a combination of the following reasons: Overtopping caused by floods that exceed the capacity of the dam (inadequate spillway capacity); Prolonged periods of rainfall and flooding; Deliberate acts of sabotage (terrorism); Structural failure of materials used in dam construction; Movement and/or failure of the foundation supporting the dam; Settlement and cracking of concrete or embankment dams; Piping and internal erosion of soil in embankment dams; Inadequate or negligent operation, maintenance and upkeep; Failure of upstream dams on the same waterway; or Earthquake (liquefaction / landslides) (FEMA, 2010). The Town of Blooming Grove Planning Committee indicated that ground failure due to saturated soils is also a concern in the County. Historic areas of concern include Route 88 embankment failure between Exits 2 and 3 and Airport Road Exit (Route 71) embankment failure next to Route 17 (Town of Blooming Grove Meeting, 2012). Extent In the case of riverine or flash flooding, once a river reaches flood stage, the flood extent or severity categories used by the NWS include minor flooding, moderate flooding, and major flooding. Each category has a definition based on property damage and public threat: Minor Flooding - minimal or no property damage, but possibly some public threat or inconvenience. Moderate Flooding - some inundation of structures and roads near streams. Some evacuations of people and/or transfer of property to higher elevations are necessary. Major Flooding - extensive inundation of structures and roads. Significant evacuations of people and/or transfer of property to higher elevations (NWS, 2011). The severity of a flood depends not only on the amount of water that accumulates in a period of time, but also on the land's ability to manage this water. One element is the size of rivers and streams in an area; but an equally important factor is the land's absorbency. When it rains, soil acts as a sponge. When the land is saturated or frozen, infiltration into the ground slows and any more water that accumulates must flow as runoff (Harris, 2001). Flood severity from a dam failure can be measured with a low, medium or high severity, which are further defined as follows: DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

4 Low severity - No buildings are washed off their foundations; structures are exposed to depths of less than 10 feet. Medium severity - Homes are destroyed but trees or mangled homes remain for people to seek refuge in or on; structures are exposed to depths of more than 10 feet. High severity - Floodwaters sweep the area clean and nothing remains. Locations are flooded by the near instantaneous failure of a concrete dam, or an earthfill dam that turns into "jello" and washes out in seconds rather than minutes or hours. In addition, the flooding caused by the dam failure sweeps the area clean and little or no evidence of the prior human habitation remains after the floodwater recedes (Graham, 1999). Two factors which influence the potential severity of a full or partial dam failure include (1) The amount of water impounded; and (2) The density, type, and value of development and infrastructure located downstream (City of Sacramento Development Service Department, 2005). Location Flooding is the primary natural hazard in New York State because the State exhibits a unique blend of climatological and meteorological features that influence the potential for flooding. These factors include topography, elevations, latitude and water bodies and waterways. Flooding is the primary natural hazard in New York State and they occur in every part of the State. Some areas are more flood-prone than others, but no area is exempt, including the Town of Blooming Grove Planning Area. The NYSDEC conducted a vulnerability assessment that depicted how vulnerable a jurisdiction may be to flood hazards. This was determined by a rating score; each county accumulated points based on the value of each vulnerability indicator. The higher the indication for flood exposure, the more points assigned, resulting in a final rating score. The result of this assessment presented an indication of a county or town s vulnerability to the flood hazard. Orange County s (which includes the Town of Blooming Grove) rating is 28, out of a possible 35. Orange County s ranking makes it the 7 th most vulnerable county to the flood hazard in New York State. The rating was based on number of NFIP insurance policies, number of NFIP claims, total amount of NFIP claims, total amount of NFIP policy coverage, number of repetitive flood loss properties, and number of flood disasters (NYS HMP 2011). Riverine flooding problems are most severe in the Delaware, Susquehanna, Chemung, Erie-Niagara, Genesse, Allegany, Hudson and Mohawk River Basins (NYS HMP 2011). Town of Blooming Grove is part of the Lower Hudson Drainage Basins (NYSDEC, Date Unknown). Please refer to Section 4 (Regional Profile) for detailed information regarding the river basins and the hydrography/hydrology of the County. Moodna Creek Watershed The Blooming Grove Planning Area is located within the Moodna Creek Watershed. For detailed information regarding the description of the Watershed, see Section 4 (Regional Profile). One of the major issues identified in the Watershed is flooding and the damages caused by flooding events. Certain areas of the Watershed have experienced numerous floods and associated damages caused by multiple flood events over the last several years. The following waterbodies located within the Planning Area have all overflowed their banks and flooded roadways after a significant rainfall event on April 15, 2007: Cromline Creek (Town of Blooming Grove) closed at least half of Cherry Hill Road and a portion of Tuthill Road. DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

5 Satterly Creek (Town of Blooming Grove and Village of South Blooming Grove) closed a portion of Peddler Hill Road and all of Stone Gate Drive (Village of South Blooming Grove) and Barnes Road (Town of Blooming Grove). An unnamed tributary of Satterly Creek closed much of Prospect Road (Village of South Blooming Grove). Perry Creek (Town of Blooming Grove) closed an extensive portion of Mountain Lodge Road and all of Perry Creek Road. Unnamed Tributary of Youngs Brook (Town of Blooming Grove) flooded a significant portion of Quaker Hill Road (Orange County Water Authority, 2010). FEMA Flood Hazard Areas According to FEMA, flood hazard areas are defined as areas that are shown to be inundated by a flood of a given magnitude on a map. These areas are determined using statistical analyses of records of riverflow, storm tides, and rainfall; information obtained through consultation with the community; floodplain topographic surveys; and hydrologic and hydraulic analyses. Flood hazard areas are delineated on FEMA s Flood Insurance Rate Maps (FIRM), which are official maps of a community on which the Federal Insurance and Mitigation Administration has indicated both the Special Flood Hazard Areas (SFHA) and the risk premium zones applicable to the community. These maps identify the SFHAs; the location of a specific property in relation to the SFHA; the base (100-year) flood elevation (BFE) at a specific site; the magnitude of a flood hazard in a specific area; the undeveloped coastal barriers where flood insurance is not available and locates regulatory floodways and floodplain boundaries (100-year and 500-year floodplain boundaries) (FEMA, 2003; FEMA, 2005; FEMA, 2008). The land area covered by the floodwaters of the base flood is the SFHA on NFIP maps. It is the area where the NFIP floodplain management regulations must be enforced and the area where the mandatory purchase of flood insurance applies. The SFHA includes Zones A, AO, AH, A1-30, AE, A99, AR, AR/A1-30, AR/AE, AR/AO, AR/AH, AR/A, VO, V1-30, VE and V (FEMA, 2010). This regulatory boundary is a convenient tool for assessing vulnerability and risk in flood-prone communities since many communities have maps showing the extent of the base flood and likely depths that will be experienced. The base flood is often referred to as the 100-year flood designation (or 1% annual chance event). The BFE on a FIRM is the elevation of a base flood event, or a flood which has a 1-percent chance of occurring in any given year as defined by the NFIP. The BFE describes the exact elevation of the water that will result from a given discharge level, which is one of the most important factors used in estimating the potential damage to occur in a given area. A structure located within a 1% (100-year) floodplain has a 26-percent chance of suffering flood damage during the term of a 30-year mortgage. The 100-year flood is a regulatory standard used by Federal agencies and most states, to administer floodplain management programs. The 1% (100-year) annual chance flood is used by the NFIP as the basis for insurance requirements nationwide. FIRMs also depict 500-year flood designations, which is a boundary of the flood that has a 0.2-percent chance of being equaled or exceeded in any given year (FEMA, 2003; FEMA, 2005). NFIP identifies that there are 91 NFIP policyholders in the Town of Blooming Grove, 86 in the Village of South Blooming Grove, and 108 in the Village of Washingtonville as of February 28, 2013; with over $6 million in claims (structure and contents) paid as of 2/28/2013 (FEMA, NFIP 2013). It is important to recognize, however, that flood events and flood risk is not limited to the NFIP delineated flood hazard areas. In the Town of Blooming Grove Planning Area, structures and infrastructure outside of currently mapped floodplains may also be at risk of significant flood impacts. Developing and maintaining accurate flood risk maps is an ongoing process involving direct input from the impacted communities and the county, and such mapping will only ever be able to help identify areas DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

6 of statistically higher risk within the limits of current science and understanding of the myriad of factors (weather, topography, hydrology and hydraulics, development, etc.) that affect flooding the region. Flood Insurance Study (FIS) In addition to FIRM and DFIRMs, FEMA also provides FISs for entire counties and individual jurisdictions. These studies aid in the administration of the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of They are narrative reports of countywide flood hazards, including descriptions of the flood areas studied and the engineered methods used, principal flood problems, flood protection measures and graphic profiles of the flood sources (FEMA, Date Unknown). A countywide FIS for Orange County was completed in August, The FIS states that flooding may occur in Orange County during any season of the year, but it is most likely to occur in the late winter-early spring months, or between January and May, when melting snow may combine with spring rains to produce increased runoff. During the winter, flooding has been a threat when ice and debris jam in the channel and at the bridges. Summer and fall floods occur due to hurricane and thunderstorm activity (FEMA FIS, 2009). The following discussion presents flood information as directly provided in the FEMA FIS document(s) and in the Orange County HMP. The 2009 FIS discussed the principal flood problems in Orange County, and reported the following information on jurisdictions within the Town of Blooming Grove Planning Area. Town of Blooming Grove The Town is reported as having the fifth most repetitive loss properties of all jurisdictions in Orange County. Flooding sources recorded in the Orange County FIS include the Cromline Creek/Seely Brook at the Town of Blooming Grove and Town of Chester corporate limits; and the Moodna Creek at the corporate limits of the Town of Blooming Grove and Town of Cornwall, and at the downstream corporate limit of Town of Blooming Grove (FEMA FIS, 2009). Village South Blooming Grove Of the 40 municipalities participating in the Orange County NFIP, the Village of South Blooming Grove was one of only four which had not experienced any flood damage resulting in NFIP payments (Orange County HMP, 2011). Village of Washingtonville Over 60% of all NFIP losses (dollar loss amounts) in Orange County have occurred in three municipalities one of those being the Village of Washingtonville. The Village is reported as having the most repetitive loss properties by number, with two properties that are recorded as having experienced 10 and 13 losses each. The Village also has the second-most total payouts for flood damage of all Orange County jurisdictions (Orange County HMP, 2011). Ice Jam Hazard Areas Ice jams are common in the Northeast U.S. and New York is not an exception. In fact, according to the USACE, New York State ranks second in the U.S. for total number of ice jam events, with over 1,500 incidents documented between 1867 and Areas of New York State that include characteristics lending to ice jam flooding include the northern counties of the Finger Lakes region and far western New York, the Mohawk Valley of central and eastern New York State, and the North Country (NYS HMP 2011). Figure The Ice Jam Database, maintained by the Ice Engineering Group at the USACE Cold Regions Research and Engineering Laboratory (CRREL), currently consists of over 18,000 records from DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

7 across the U.S. The USACE CRREL Ice Jam Database, NYS HMP and various other sources, indicates that there have not been any ice jam events in the Town of Blooming Grove or in its hamlets and villages between 1857 and 2013 (Ice Engineering Research Group, 2013). Dam Break Hazard Area According to the NYSDEC Division of Water Bureau of Flood Protection and Dam Safety, the hazard classification of a dam is assigned according to the potential impacts of a dam failure pursuant to 6 NYCRR Part Dams are classified in terms of potential for downstream damage if the dam were to fail. These hazard classifications are identified and defined below: Low Hazard (Class A) is a dam located in an area where failure will damage nothing more than isolated buildings, undeveloped lands, or township or county roads and/or will cause no significant economic loss or serious environmental damage. Failure or mis-operation would result in no probable loss of human life. Losses are principally limited to the owner's property Intermediate Hazard (Class B) is a dam located in an area where failure may damage isolated homes, main highways, minor railroads, interrupt the use of relatively important public utilities, and/or will cause significant economic loss or serious environmental damage. Failure or misoperation would result in no probable loss of human life, but can cause economic loss, environment damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be located in areas with population and significant infrastructure. High Hazard (Class C) is a dam located in an area where failure may cause loss of human life, serious damage to homes, industrial or commercial buildings, important public utilities, main highways or railroads and/or will cause extensive economic loss. This is a downstream hazard classification for dams in which more than 6 lives would be in jeopardy and excessive economic loss (urban area including extensive community, industry, agriculture, or outstanding natural resources) would occur as a direct result of dam failure (NYSDEC, Date Unknown). There are currently 297 dams in Orange County, 22 of which are classified as High Hazard Potential (C), 48 as Moderate Hazard Potential (B), and 198 as Low Hazard Potential (A). The remaining structures are classified as are Negligible, or No Hazard Potential (D). Details of the recorded ownership of these dams are kept on file by NYSDEC. None of the NYSDEC-listed dams are classified by USGS as a major dam, or a dam representative of the most significant potential hazard consequences due to a failure. Three dams classified as High Hazard by NYSDEC, and four (4) classified as Medium Hazard (B) are located in the Town of Blooming Grove, with two (2) additional dams classified as Medium Hazard (B) located in the Village of South Blooming Grove. There are 10 Low Hazard potential dams in the Planning Area. Table below presents details for all dams in the Town of Blooming Grove Planning Area classified as of high or medium hazard potential by the NYSDEC. Table High or Medium Hazard Dams in the Town of Blooming Grove Dam Name Municipality River/Stream Maximum Storage (Acre- Feet) Dam Height (Feet) Beaver Dam Lake Dam Blooming Grove Tr-Moodna Creek Hazard Potential USACE / NYSDEC EAP on File 2, C No Tomahawk Lake Dam Blooming Grove Cromline Creek 3, C DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

8 Dam Name Municipality River/Stream Willow Brook Dam (aka Orange and Rockland Dam) Schoonmaker Lake Dam Blooming Grove Blooming Grove Satterly Creek Maximum Storage (Acre- Feet) Dam Height (Feet) Hazard Potential USACE / NYSDEC EAP on File C B William Curtis Dam Blooming Grove B Stuts Dam Blooming Grove B Sallisbury Mills Dam Blooming Grove B Lake Hildegarde Dam Merriewold Lake Dam Gagliardi Dam Source: NYSDEC South Blooming Grove (V) South Blooming Grove (V) South Blooming Grove (V) Satterly Creek B 32 B Additional documentation provided the following information regarding location of potential flooding due to dam failure in the Town of Blooming Grove Planning Area: Willow Brook Dam: A dam failure or flooding would inundate downstream areas along the Museum Village Road, which passes approximately 40 feet downstream of the dam. A dam failure would release a high discharge flow over the road, making the route impassable. The next potential hazard area would be the community of Bull Mine, although water surface elevation in the event of a dam failure would raise less than two feet as it passes through the community (Willow Brook Dam EAP, 2003). Merriewold Lake Dam: Four roads cross Sattery Creek, as it runs from the Merriewold Dam to the Moodna Creek, a length of approximately 4.5 miles. The Main Entrance Road, Round Hill Road, Horton Road, and Hudson Road would all be flooded in the case of a dam failure. In addition, North Drive and a portion of Bernas Road would be flooded. The next potential hazard area would be the downstream communities at the Tappan Homes and Rolling Meadows Developments (Merriewold Lake Dam EAP, 2012). Additional documentation provided the following information regarding location of potential flooding in the Town of Blooming Grove Planning Area: Town of Blooming Grove The Town of Blooming Grove has identified the following floodprone areas: o Tappan Homes Subdivision damage to homes, water/sewer plant, roads, drainage structures. o Mt. Lodge Park/Glenwood Community road and homes damage DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

9 o Mt. Lodge Road flooding o Clove Road flooding o Tuthill Road o Cardinal Drive o Salisbury Mills area o Route 94 o Hudson Drive o Horton Road o Museum Village Road o Central Garage Flooding o Salisbury Mills Fire Department Headquarters o Mays Field Recreation Complex o Other Roadways in need of Drainage Improvements Hulsetown Road Goshen Road Station Road Farmingdale Road Prospect Road o Bull Mine Road Village of South Blooming Grove - The Village of South Blooming Grove has identified the following flood-prone areas: o Satterly Creek Basin and surrounding areas o Merriewold Lake dam spillway o Peddler Hill Dam and Road o Stonegate Drive stream crossing and culvert o Culverts at Merriewold Lane North and Lakeshore drive Village of Washingtonville There are several flood-prone areas within the Village, including several repetitive loss properties. The Village has identified the downtown area as a flood hazard area. This area consists of residential and commercial properties and has flooded with up to eight feet of water between municipal boundaries at both ends of State Route 94. Damages resulted in the demolition of the Village Hall and damages and/or losses to approximately 80 homes. Flooding incapacitates the Village s emergency services, government and public works. Previous Occurrences and Losses Many sources provided historical information regarding previous occurrences and losses associated with flooding events throughout New York State, Orange County, and the Town of Blooming Grove Planning Area. With so many sources reviewed for the purpose of this HMP, loss and impact information for many events could vary depending on the source. Therefore, the accuracy of monetary figures discussed is based only on the available information identified during research for this HMP. NOAA s NCDC storm events database indicates that Orange County was impacted by approximately 84 flood events between 1950 and December 31, Total property damages, as a result of these flood events, were estimated at over $6.4 million. This total includes damages to all jurisdictions in the county, and may also include damages to other counties. Six of those NCDC flood event records were reported as DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

10 occurring Countywide, and five of the records reported damages to jurisdictions specifically within the Blooming Grove Planning Area. According to the Hazard Research Lab at the University of South Carolina s Spatial Hazard Events and Losses Database for the U.S. (SHELDUS), between 1960 and 2012, 43 flood events occurred within Orange County. The database indicated that flood events and losses specifically associated with Orange County and its municipalities totaled over $55.6 million in property damage and over $1.03 million in crop damage. However, these numbers may vary due to the database identifying the location of the hazard event in various forms or throughout multiple counties or regions. Between 1954 and 2012, FEMA declared that New York State experienced 39 flood-related disasters (DR) or emergencies (EM) classified as one or a combination of the following disaster types: coastal storms, flooding, flash flooding, heavy rain, high winds, high tide, hurricane, ice storm, landslides, severe storms, tropical storm, and wave action. Generally, these disasters cover a wide region of the State; therefore, they may have impacted many counties. However, not all counties were included in the disaster declarations. Of those events, the NYS HMP and other sources indicate that Orange County and the Town of Blooming Grove Planning Area have been declared as a disaster area as a result of nine flood events (FEMA, 2013). Figure shows the FEMA disaster declarations (DR) (and does not indicate emergency (EM) declarations) for flooding events in New York State, from 1953 to June This figure indicates that Orange County was included in eight disaster declarations. Since the date of this figure, Orange County has not been included in any additional FEMA disaster declaration for flooding. DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

11 Figure Presidential Disaster Declarations for Flooding Events, Source: NYS HMP 2011 Note: The black circle indicates the approximate location of Orange County. Based on all sources researched, known flooding events that have affected the Town of Blooming Grove Planning Area are identified in Table With flood documentation for New York State being so extensive, not all sources have been identified or researched. Therefore, Table may not include all events that have occurred throughout the Planning Area. DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

12 Table Flooding Events Between 1950 and 2013 FEMA Dates of County Event Type Declaration Event Designated? Number August 12-19, 1955 September 13, 1971 March 28, 1984 April 8, 1984 April 16, 1993 Remnants of Hurricanes Connie and Diane Severe storms, flooding Coastal storms, flooding Flood/ flash flood DR-45 DR-311 DR-702 N/A N/A Losses / Impacts Flooding throughout the Planning Area that caused evacuations. Flooding caused damage to residential and commercial properties, road closures, and power outages. This storm caused seven deaths and $147.6 M in damages throughout its path. New York State experienced approximately $7.4 M in total eligible damages. Flooding occurred across southeastern New York State, and a federal disaster designation was declared on April 17. Flooding caused road closures in the Blooming Grove Planning Area. Orange County experienced approximately $11.9M in total eligible damages. Showers and thunderstorms dumped between one and two inches of rain across the area. Localized, but significant urban flooding resulted from these torrential rains. Source(s) Planning Area Input FEMA, Orange County HMP FEMA, Orange County HMP, Planning Area Input NOAA-NCDC, Orange County HMP October 21, 1995 November 12, 1995 Urban flood N/A N/A No damages were reported/ available. NOAA-NCDC Urban flood N/A N/A No damages were reported/ available. NOAA-NCDC January Severe storms/ flooding/ Urban/ small stream flood DR-1095 Severe storms and flooding across the region from January th led to road damage across Orange County. Orange County was among many counties in New York State that became eligible for Individual and Public Assistance under Federal Disaster Declaration DR Storm-induced damages to County roads at 32 locations resulted in approximately $330,000 in damages. FEMA, NOAA-NCDC, Orange County HMP April 16, 1996 July 25, 1996 Urban/ small stream flood Heavy Rain/ Flood N/A N/A No damages were reported/ available. NOAA-NCDC N/A N/A Clusters of strong thunderstorms brought two to four inches of rain across central parts of Orange County. Torrential rain caused flash flooding of numerous roads, small streams, and basements throughout this area. Total rainfall of four inches was measured in the Village of Goshen. Significant basement flooding occurred in the Villages of Goshen and Washingtonville. No damages were reported/ available. NOAA-NCDC, Orange County HMP DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

13 Dates of Event Event Type FEMA Declaration Number County Designated? Losses / Impacts Source(s) May 10, 1998 Flash flood N/A N/A With wet antecedent conditions during the past 11 days, bands of heavy rainfall caused flash flooding in Orange County, where police reported flooded basements and roads countywide. Torrential record rainfall, which caused serious widespread urban, small stream, and river flooding, preceded the remnants of Hurricane Floyd. Orange, Putnam, Rockland, and Westchester Counties were declared disaster areas. NOAA-NCDC, Orange County HMP September 16 17, 1999 Flood EM-3149 No Serious widespread flooding of low-lying and poor drainage areas resulted in the closure of many roads and basement flooding across the entire region. Orange County experienced $1.7M in damages. NOAA-NCDC, Orange County HMP, SHELDUS, Planning Area Input October 8-9, 1996 Heavy Rain N/A N/A In the Blooming Grove Planning Area, flooding caused damage to private properties, local bridges, roads, culverts and the Tappan Water and Wastewater Plants. In the Blooming Grove Planning Area, flooding caused damage to private properties, local bridges, roads, culverts and the Tappan Water and Wastewater Plants. Planning Area Input September 15-18, 1999 Remnants of Hurricane/Tro pical Storm Floyd DR-1296 Heavy rain caused flooding which damaged private properties, local bridges, roads, culverts, the Tappan Water and Wastewater Plants, Moffat Library, and Mays Field Recreational Complex. Planning Area Input, FEMA December 17, 2000 Flash flood N/A N/A Heavy rain caused significant flooding in Orange County, where three to four inches of rain fell mainly across western and northern Orange County. Widespread flash flooding of low lying and poor drainage areas occurred at several locations throughout the County. Rainfall amounts ranged from 2.11 inches at Gardnerville to 2.8 inches at Sterling Forest. Serious flooding occurred in parts of Mountain Lodge Park in Blooming Grove, where some trails partially washed away. No damages were reported/ available. NOAA-NCDC DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

14 Dates of Event Event Type FEMA Declaration Number County Designated? Losses / Impacts Source(s) August 13 September 16, 2004 Severe Storms and Flooding DR-1564 The remnants of a tropical system combined with thunderstorms moved over Western Orange County, where hourly rainfall estimates in the three to five inches was observed at times. Houses were damaged, roads were destroyed, and buildings collapsed throughout Western Orange County. A federal disaster declaration was made on October 1. Damage estimates were $2.2 M in public and $1.8 M in private property. As of April 2013, $2.8 M in FEMA Individual Assistance and $14 M in Public Assistance Grants were approved and obligated throughout New York State. According to SHELDUS, Orange County experienced approximately $4 M in damages. FEMA, Orange County HMP Between April 2 nd and 3 rd, a low pressure system passed over the Appalachian Mountains and moved slowly west of Orange County, bringing widespread heavy rain, heavy showers, and thunderstorms. The storm followed another heavy rain event from three to five days earlier, which primed the area for flooding. April 2 4, 2005 Severe Storms and Flooding DR-1589 Heavy rain caused widespread urban flooding throughout Orange County. Most small streams and rivers overflowed their banks. In addition, high wind gusts from 46 to 57 mph, associated with heavier showers, downed trees. Select rainfall amounts for Orange County included 2.00 inches at the Town of Blooming Grove to 3.80 inches at the Town of Monroe. FEMA, NOAA-NCDC, Orange County HMP According to SHELDUS, Orange County experienced approximately $4.2M in damages. June 26 July 10, 2005 Severe Storms and Flooding DR-1650 A federal disaster was declared on July 1. Orange County experienced approximately $246.3 M in total eligible damages. FEMA, Orange County HMP DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

15 Dates of Event October 8 9, 2005 Event Type FEMA Declaration Number County Designated? Flood N/A N/A Losses / Impacts Periods of heavy rain spread north across the region Friday night through Saturday, Oct 8th, ending by Sunday, Oct 9th. The heaviest rain fell north of New York City across the Lower Hudson Valley. Heavy rain resulted in significant flooding on some rivers, most small brooks and streams, and throughout urban areas in low lying and poor drainage areas. Rainfall amounts in Orange County ranged from 5.58 inches at Gardnerville to inches at New Windsor. Spotters reported flash flooding of many roads throughout Orange County. No damages were reported/ available. Source(s) NOAA-NCDC, Orange County HMP October 12, 2005 Flood N/A N/A Periods of heavy rain caused flooding of low lying and poor drainage areas throughout Orange County, including many streets. No damages were reported/ available. NOAA-NCDC April 14 18, 2007 Severe Storms and Inland and Coastal Flooding DR-1692 A Nor Easter occurred during Sunday and Monday, April 15th and 16 th. Heavy rain began during the early morning hours of the 16th, persisting into Wednesday morning on the 18th. Heavy rains and high winds caused widespread and significant river, stream, and urban flooding of low lying and poor drainage areas throughout Orange County. Rainfall in the County ranged from 4.26 inches in the Hamlet of Westtown to 8.00 inches at the Town of Cornwall. Flooding occurred as many small rivers, streams, and brooks rose over their banks within 12 hours of the heavy rain on April 15th. The Wallkill River rose over its' banks the following day, on Monday, April 16th. Moodna Creek flooded houses at Washingtonville. The Orange County Department of Emergency Services reported emergency declarations in the Towns of Deerpark and Blooming Grove and in the Villages of Washingtonville, Greenwood Lake, and South Blooming Grove. Many road closures were reported in the Town of Blooming Grove and many other towns and villages throughout the county. Evacuations occurred in the Village of Washingtonville. In the Village of South Blooming Grove, village baseball fields were flooded and damaged. FEMA, NOAA-NCDC, SHELDUS, Planning Area Input On April 24th, a federal disaster was declared for the state of New York from the effects of severe storms and inland and coastal flooding during the period of April New York State experienced millions in eligible damages, and FEMA gave out more than $61 million in assistance to affected counties within the DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

16 Dates of Event Event Type FEMA Declaration Number County Designated? Losses / Impacts State. Property damages in Orange County were estimated at $12.8M. As of July, 2007, more than $2.4M in FEMA disaster assistance had been awarded to Orange County. Source(s) March 8, 2008 Flood N/A N/A Numerous flooded basements had to be pumped out in residential areas of Middletown and Washingtonville. Route 78 near Aspin Rd/Wisner Avenue was also closed due to flooding. No damages were reported/ available. Orange County HMP March 13 31, 2010 March 7, 2011 August 28, 2011 Heavy Rain/ Snow Melt/ Severe Storms and Flooding Heavy Rain/ Snowmelt Flood/ Remnants of Hurricane Irene DR-1899 N/A DR-4020 N/A A Nor'easter produced an extended period of heavy rainfall across the area on March 13, causing widespread flooding across portions of southeast New York. Moodna Creek and other small streams exceeded their banks in the Village of Washingtonville, and caused numerous houses to be inundated with water. In the Town of Blooming Grove Planning Area, rainfall totals on the 13 th included 1.63 inches in the Village of Washingtonville. In the Village of Washingtonville, widespread flooding damaged 150 private properties, school facilities, the police and fire stations, Village offices, and recreational facilities. In the Village of South Blooming Grove, flooding from the storms damaged five private properties, local bridges, roads, culverts, and the sewer pump station. Heavy rainfall resulted in moderate to major flooding across portions of Southeast New York. In the Village of Washingtonville, Moodna Creek overflowed its banks causing flooding of first floor residents and businesses on Route 208 as well as Route 94 near Washingtonville High School. Rainfall totals measures 0.5 inches in the Village of Washingtonville. Tropical storm Irene moved across Southeast New York on the 28 th, bringing extended periods of heavy rainfall, and resulting in widespread moderate to major flooding across the area. Moodna Creek overflowed its banks resulting in water rescues at Udderly Fresh Farms on Rt. 94 near Farmview Ln. in the Village of Washingtonville. In addition, the raging waters from the creek burst holes in the foundations of houses on Patricia and Beverly Lanes and inundated the Washingtonville Manor and Brookside NOAA-NCDC, NWS, FEMA, Planning Area Input NOAA-NCDC, NWS NWS, NOAA-NCDC, FEMA, Planning Area Input DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

17 Dates of Event Event Type FEMA Declaration Number County Designated? Losses / Impacts Acres mobile home parks, south of Main St. The surge of water also engulfed the first floor of a residence on Cardinal Drive. Rt. 94 near Goshen Ave. in the Village of Washingtonville was also closed due to flooding. In the Village of South Blooming Grove, flooding from the storm damaged eight private properties, multiple local bridges, roads, culverts, Village recreational facilities, dams and the Village Hall roof. Damages to just the Village of South Blooming Grove was estimated at over $1 M. Source(s) September 7-8, 2011 October 27 November 8, 2012 Remnants of Tropical Storm Lee Hurricane Sandy DR-4031 DR-4085 As of April 4, 2013, more than $102M in individual assistance and $459M in public assistance grants had been awarded by FEMA to affected counties in the State of New York. Specific damages for Orange county were not available at this time. Remnants of Tropical Storm Lee produced heavy rains and caused flash flooding and river flooding across parts of central New York State and northeast Pennsylvania. As of April 4, 2013, more than $55M in individual assistance and $126M in public assistance grants had been awarded by FEMA to affected counties in the State of New York. Specific damages for Orange county were not available at this time. Hurricane Sandy made landfall near Atlantic City, NJ on the 29th. Record breaking high tides and wave action was combined with sustained winds of 40 to 60 mph and wind gusts of 80 to 90 mph. Emergency managers recommended mandatory evacuations of more than 1/2 million people that lived in low lying areas. Widespread significant power outages of more than 2 million lasted up to 2 weeks. In Orange County, 0.8 inches of rainfall was reported in the Village of Washingtonville on the 29 th, and 0.5 inches on the 30 th. NWS, FEMA NWS, NOAA-NCDC, FEMA, Planning Area Input In the Planning Area, there were widespread power outages and downed trees. The water and wastewater plants were inaccessible due to road closures. In the Village of South Blooming Grove, the Village water system pumps were damaged from flooding and one injury was reported. Note (1): Monetary figures within this table were U.S. Dollar (USD) figures calculated during or within the approximate time of the event. If such an event would occur in the present day, monetary losses would be considerably higher in USDs as a result of increased U.S. Inflation Rates. DR Federal Disaster Declaration FEMA Federal Emergency Management Agency EM Federal Emergency Declaration IA Individual Assistance DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

18 K Thousand ($) M Million ($) N/A Not applicable NCDC National Climate Data Center NOAA National Oceanic Atmospheric Administration NWS National Weather Service PA Public Assistance SHELDUS Spatial Hazard Events and Losses Database for the U.S. DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

19 Agriculture-related flood disasters are quite common. One-half to two-thirds of the counties in the U.S. have been designated as disaster areas in each of the past several years. The Secretary of Agriculture is authorized to designate counties as disaster areas to make emergency loans (EM) to producers suffering losses in those counties and in counties that are contiguous to a designated county. Table summarizes the USDA disaster designations for flood-related events. Table USDA Disaster Designations Incidence Period April 14-18, 2007 May 1-3, May 16, May 20, and June 16, 2008 May 16, 2009 March 13 15, 2010 April 1 June 15, 2011 July 10 August 25, 2011 August 26 September 5, 2011 March 26 April 8, 2012 October 27 31, 2012 Event Type Severe storms and inland and coastal flooding; Excessive rain, flash flooding, and flooding Excessive rain, high winds, flooding, flash flooding, hail and lightning: Hail, High Winds, Excessive Rain Excessive Rain, Flooding, Flash Flooding, Hail and High Winds Severe Storms and Flooding Excessive rain, high winds, and hail Excessive heat and excessive rain Tropical Storm/Hurricane Irene Frosts, freezes, high winds, and hail Hurricane Sandy USDA Declaration Number M1692; S2528 S2725; S2724; S2827 S2929 M1899 S3160 S3204; S3202 M4020 S3251 M4085; N1114 County Designated?* Source: USDA, 2013 *Disaster event occurred within the county. M Presidential Major Disaster Declaration N Administrative Physical Loss Notification Losses / Impacts Production and physical losses were attributed to excessive rain, flash flooding, and flooding. The U.S. Department of Agriculture designated 19 counties in New York as primary natural disaster areas because of losses resulting from extreme weather which occurred during the period of May 1-3, 2008, and continuing. Production losses were attributed to multiple extreme weather events from May 1 to June 13, Production losses were attributed to excessive rain, flooding, flash flooding, hail and high winds. Production and physical losses were attributed to severe storms and flooding. Production and physical losses were attributed to excessive rain, high winds, and hail. Production and physical losses were attributed to excessive heat and excessive rain, and the combined effects of excessive rain, flooding, flash flooding, hail, high winds, below normal temperatures and tornadoes. Production and physical losses were attributed to the effects of Tropical Storm and Hurricane Irene. Production and physical losses were attributed to frost, freezes, high winds, and hail. Production and physical damages and losses were attributed to the combined effects of high winds excessive rain, and flash flooding associated with Hurricane Sandy, a snowstorm and a nor'easter. Source(s) USDA USDA USDA USDA USDA DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York

20 S USDA Secretarial National Disaster Determination United States Department of Agriculture According to the CRREL database, no historical ice jams have been recorded in the Town of Blooming Grove Planning Area. According to the Orange County HMP and NPDP records, there have been 43 dam failures in New York State since 1868, including two dam safety incidents in Orange County. The following details on a dam safety incident in the Town of Blooming Grove Planning Area were provided in the Orange County HMP: In September 1999, downstream residents reported concerns about the Petker and Chen Dam, a low hazard, privately owned dam of height 25 feet and normal storage 60 acre-feet in the Town of Blooming Grove. A site check of the dam conducted by regional staff of the NYSDEC revealed deficient dam maintenance and evidence of overtopping, but no apparent damage to the structure. Damage was confined to downstream driveway bridges. No other dam safety incidents in the Town of Blooming Grove Planning Area were reported. National Flood Insurance Program The U.S. Congress established the NFIP with the passage of the National Flood Insurance Act of 1968 (FEMA s 2002 National Flood Insurance Program (NFIP): Program Description). The NFIP is a Federal program enabling property owners in participating communities to purchase insurance as a protection against flood losses in exchange for State and community floodplain management regulations that reduce future flood damages. As stated in the NYS HMP, the NFIP collects and stores a vast quantity of information on insured structures, including the number and location of flood insurance policies, number of claims per insured property, dollar value of each claim and aggregate value of claims, repetitive flood loss properties, etc. NFIP data presents a strong indication of the location of flood events among other indicators (NYSDPC, 2008). There are three components to NFIP: flood insurance, floodplain management and flood hazard mapping. Nearly 20,000 communities across the U.S. and its territories participate in the NFIP by adopting and enforcing floodplain management ordinances to reduce future flood damage. In exchange, the NFIP makes federally backed flood insurance available to homeowners, renters, and business owners in these communities. Community participation in the NFIP is voluntary. Flood insurance is designed to provide an alternative to disaster assistance to reduce the escalating costs of repairing damage to buildings and their contents caused by floods. Flood damage is reduced by nearly $1 billion a year through communities implementing sound floodplain management requirements and property owners purchasing of flood insurance. Additionally, buildings constructed in compliance with NFIP building standards suffer approximately 80 percent less damage annually than those not built in compliance (FEMA, 2008). Please see Table in the Vulnerability Assessment for NFIP data for the Town of Blooming Grove Planning Area. NFIP data for Town of Blooming Grove planning area is presented further in the Vulnerability Assessment section of this profile. As an additional component of NFIP, the Community Rating System (CRS) is a voluntary incentive program that recognizes and encourages community floodplain management activities that exceed the minimum NFIP requirements. As a result, flood insurance premium rates are discounted to reflect the DMA 2000 Hazard Mitigation Plan Town of Blooming Grove Planning Area, New York