The Flood Insurance Rate Map (FIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal flood risk. The FIRM Database is derived from Flood Insurance Studies (FISs), previously published FIRMs, flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). This file is georeferenced to the Earth's surface using the Geographic Coordinate System (GCS) and North American Datum of 1983.
The Floodplain Mapping/Redelineation study deliverables depict and quantify the flood risks for the study area. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual- chance flood event, and areas of minimal flood risk. The Floodplain Mapping/Redelineation flood risk boundaries are derived from the engineering information Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA).
The Department of Water and Environmental Regulation produces floodplain mapping of rivers and major watercourses and provides floodplain development advice to ensure that proposed floodplain development has adequate flood protection and does not impact on the existing flood regime of the area. This advice is related to major river flooding only. Other issues, such as stormwater drainage and envirionmental and ecological considerations are not addressed. This dataset contains 8 extent types as follows: 1 in 10 (10%) AEP flood level contour 1 in 20 (5%) AEP flood level contour 1 in 25 (4%) AEP flood level contour 1 in 50 (2%) AEP flood level contour 1 in 100 (1%) AEP flood level contour Designated flood event level contour 1 in 200 (0.5%) AEP flood level contour 1 in 500 (0.2%) AEP flood level contour This dataset describes how flood levels vary across the floodplain for various sized flood events. Flood levels are referenced to the Australian Height Datum (AHD) Note: To see the full scope of the floodplain mapping, 12 dataset layers are required to be loaded in the following order: FLOODPLAIN DATASET LAYERS: FPM Flood Level Points (m AHD) FPM Flood Level Contours (m AHD) FPM 1 in 100 (1%) AEP Floodway and Flood Fringe Line FPM Extent of Flooding FPM Levee Banks FPM Location of Cross Sections FPM 1 in 100 (1%) AEP Floodplain Development Control Area FPM Map Index FPM Bridges FPM Special Development Condition Area FPM 1 in 100 (1%) AEP Floodway and Flood Fringe Area FPM Floodplain Area The dataset covers the following areas: Avon River - Brookton Townsite. Collie River - Collie Townsite. Fitzroy River – Fitzroy Crossing Townsite. Gascoyne River - Carnarvon Townsite and the Lower Gascoyne (contains both pre and post-stage 2 Carnarvon flood mitigation works mapping: refer to COMMENTS field) Greenough River – Indian Ocean to Walkaway. Katanning Townsite. Lower Collie River, Brunswick River and Wellesley River - Greater Bunbury. Preston River - Donnybrook Townsite. Serpentine River, Peel, Birrega & Oaklands Drains, Murray River and the Peel Inlet / Harvey Estuary - Peel Inlet to the confluence of the Dandalup-South Dandalup-North Dandalup Rivers and south to the Darling Scarp via Pinjarra (Murray River), Peel Inlet to Black Lake (Nambellup Brook) and Geogrup Lake to South Western Highway (Serpentine River), north to Wellard (Peel Main Drain) and to Wungong Brook (Birrega Drain). Swan River, Canning River and Tributaries: Perth - Fremantle to Walyunga National Park (Swan River) and Canning Bridge to Brookton Highway (Canning River). Tributaries include Bennett Brook, Blackadder Creek, Ellen Brook, Helena River, Henley Brook, Jane Brook, St Leonards Creek, Susannah Brook (Swan River) and Southern River/ Wungong Brook (Canning River). For further information on flooding and floodplain management in Western Australia please refer to our Water Facts publications: Flooding in Western Australia (Water facts 13) and Floodplain Management (Water facts 14). This information is available at the following addresses: https://www.wa.gov.au/system/files/2022-11/Water-facts-14-Floodplain-management.pdf https://www.wa.gov.au/system/files/2022-11/Water-facts-14-Floodplain-management.pdf Glossary: Annual exceedance probability (AEP) - the likelihood of occurrence of a flood of a given size or larger in any one year; usually expressed as a percentage. 1 in 100 AEP flood - this means that there is a 1 in 100 (or 1%) chance of a flow of this size or larger occurring in any one year. This flood has a 50% chance of being experienced at least once in a person's life time. The 1 in 100 AEP flood has been generally adopted in Australia and overseas as the basis for floodplain management planning. Floodplain - the portion of a river valley next to the river channel which is covered with water when the river overflows its banks during major river flows. The term also applies to land adjacent to estuaries which is subject to flooding. Australian Height Datum (AHD) - is a geodetic datum for altitude measurement in Australia. It was adopted in 1971 by the National Mapping Council as the datum to which all vertical control for mapping is to be referred. The datum is based on the mean sea level (1966-1968) being assigned the value 0.000m on the Australian Height Datum (AHD) at 30 tide gauges around the coast of the Australian continent.
The Flood Insurance Rate Map (FIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal flood risk. The FIRM Database is derived from Flood Insurance Studies (FISs), previously published FIRMs, flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). This file is georeferenced to the Earth's surface using the Geographic Coordinate System (GCS) and North American Datum of 1983.
The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual- chance flood event, and areas of minimal flood risk. The DFIRM Database is derived from Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). The file is georeferenced to earth?s surface using the UTM projection and coordinate system. The specifications for the horizontal control of DFIRM data files are consistent with those required for mapping at a scale of 1:12,000.
The Flood Insurance Rate Map (FIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal flood risk. The FIRM Database is derived from Flood Insurance Studies (FISs), previously published FIRMs, flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). This file is georeferenced to the Earth's surface using the Geographic Coordinate System (GCS) and North American Datum of 1983.
The Department of Water and Environmental Regulation produces floodplain mapping of rivers and major watercourses and provides floodplain development advice to ensure that proposed floodplain …Show full descriptionThe Department of Water and Environmental Regulation produces floodplain mapping of rivers and major watercourses and provides floodplain development advice to ensure that proposed floodplain development has adequate flood protection and does not impact on the existing flood regime of the area. This advice is related to major river flooding only. Other issues, such as stormwater drainage and environmental and ecological considerations are not addressed. Both the floodway and flood fringe make up the 1 in 100 (1%) annual exceedance probability (AEP) floodplain, however there are areas where the floodplain exists, but the floodway and flood fringe does not. In such situations, a different floodplain management strategy applies (for example, the Swan River between the Narrows and Canning Bridges). This dataset contains four lines - Floodway limit, Extent of 1 in 100 (1%) AEP flooding, Extent of floodway & Extent of study. The Floodway limit, Extent of floodway and Extent of 1 in 100 (1%) AEP Flooding and Extent of study line types are boundaries which appropriately overlay over the "FPM 1 in 100 (1%) AEP Floodway and Flood Fringe Areas" (polygon) dataset. Note: To see the full scope of the floodplain mapping, 12 dataset layers are required to be loaded in the following order: FLOODPLAIN DATASET LAYERS: FPM Flood Level Points (m AHD) FPM Flood Level Contours (m AHD) FPM 1 in 100 (1%) AEP Floodway and Flood Fringe Line FPM Extent of Flooding FPM Levee Banks FPM Location of Cross Sections FPM 1 in 100 (1%) AEP Floodplain Development Control Area FPM Map Index FPM Bridges FPM Special Development Condition Area FPM 1 in 100 (1%) AEP Floodway and Flood Fringe Area FPM Floodplain Area The dataset covers the following areas: Avon River – Toodyay, Northam, York and Beverley Townsites. Blackwood River – Augusta, Bridgetown, Nannup and Boyup Brook Townsites. Brunswick River - Greater Bunbury Coblinine River & Dorderyemunning Creek - Wagin Townsite. Collie River - Collie Townsite. Chapman River – Geraldton Townsite. Denmark River – Denmark Townsite. Gascoyne River - Carnarvon Townsite and the Lower Gascoyne. Gribble Creek - Kalgoorlie Townsite. Harding River - Roebourne Townsite. Irwin River - Dongara Townsite. Lower Collie River - Greater Bunbury. Preston River - Donnybrook Townsite. Serpentine River, Peel, Birrega & Oaklands Drains, Murray River and the Peel Inlet / Harvey Estuary - Peel Inlet / Harvey Estuary to Pinjarra and south to the Darling Scarp (Murray River) and Peel Inlet / Harvey Estuary to Wellard (Peel Main Drain), east to South Western Highway (Serpentine River) and north to Wungong Brook (Birrega Drain). Swan River, Canning River and Tributaries: Perth - Fremantle to Walyunga National Park (Swan River) and Canning Bridge to Brookton Highway (Canning River). Tributaries include Bennett Brook, Blackadder Creek, Ellen Brook, Helena River, Henley Brook, Jane Brook, St Leonards Creek, Susannah Brook (Swan River) and Southern River/ Wungong Brook (Canning River). Toby Inlet – Quindalup Townsite. Vasse-Wonnerup Estuaries, Broadwater and New River - Busselton Townsite. For further information on flooding and floodplain management in Western Australia, please refer to our Water Facts publications: Flooding in Western Australia (Water facts 13) and Floodplain Management (Water facts 14). This information is available at the following addresses: https://www.wa.gov.au/system/files/2022-11/Water-facts-13-Flooding-in-Western-Australia.pdf https://www.wa.gov.au/system/files/2022-11/Water-facts-14-Floodplain-management.pdf Glossary: Annual exceedance probability (AEP) - the likelihood of occurrence of a flood of a given size or larger in any one year; usually expressed as a percentage. 1 in 100 AEP flood - this means that there is a 1 in 100 (or 1%) chance of a flow of this size or larger occurring in any one year. This flood has a 50% chance of being experienced at least once in a person's lifetime. The 1 in 100 AEP flood has been generally adopted in Australia and overseas as the basis for floodplain management planning. Flood fringe - the area of the floodplain, outside of the floodway where development could be permitted provided it is compatible with flood hazard and building conditions provide an adequate level of flood protection. These areas are generally covered by still or very slowly moving waters during a 1 in 100 (1%) AEP flood. Floodplain - the portion of a river valley next to the river channel which is covered with water when the river overflows its banks during major river flows. The term also applies to land adjacent to estuaries which is subject to flooding. Floodway - the river channel and a portion of the floodplain where a significant flow or storage of water occurs during floods. If the floodway is even partially blocked, then the natural flooding regime of the area may be detrimentally impacted with flood levels being raised and affecting areas which may not have been previously affected. Development in floodways is to be avoided wherever possible. Australian Height Datum (AHD) - is a geodetic datum for altitude measurement in Australia. It was adopted in 1971 by the National Mapping Council as the datum to which all vertical control for mapping is to be referred. The datum is based on the mean sea level (1966-1968) being assigned the value 0.000m on the Australian Height Datum (AHD) at 30 tide gauges around the coast of the Australian continent.
The S_FIRM_Pan table contains information about the FIRM panel area. A spatial file with location information also corresponds with this data table. The spatial entities representing FIRM panels are polygons. The polygon for the FIRM panel corresponds to the panel neatlines. Panel boundaries are generally derived from USGS DOQQ boundaries. As a result, the panels are generally rectangular. In situations where a portion of a panel lies outside the jurisdiction being mapped, the user must refer to the S_Pol_Ar table to determine the portion of the panel area where the FIRM Database shows the effective flood hazard data for the mapped jurisdiction. This information is needed for the FIRM Panel Index and the following tables in the FIS report: Listing of NFIP Jurisdictions, Levees, Incorporated Letters of Map Change, and Coastal Barrier Resources System Information.
The spatial entities representing FIRM panels are polygons. The polygon for the FIRM panel corresponds to the panel neatlines. Panel boundaries are generally derived from USGS DOQQ boundaries. As a result, the panels are generally rectangular. FIRM panels must not overlap or have gaps within a study. In situations where a portion of a panel lies outside the jurisdiction being mapped, the user must refer to the S_Pol_Ar table to determine the portion of the panel area where the FIRM Database shows the effective flood hazard data for the mapped jurisdiction.
This information is needed for the FIRM Panel Index and the following tables in the FIS report: Listing of NFIP Jurisdictions, Levees, Incorporated Letters of Map Change, and Coastal Barrier Resources System Information.
This layer is a component of Region Preliminary Data.
Data Disclaimer for Use of Pierce County GIS DataThe purpose of this data is to show the base flood elevation at the modeled cross sections for identified areas that have a 1% chance flooding in any given year (i.e. 1 in 100 chance per year or base flood). The cross section represents the most accurate depiction of flood risk of all the mapping products as it is the foundational data of the hydraulic modeling. Most of the hydraulic models in the countywide flood insurance study also ran scenarios for the 0.2% annual chance flood (i.e. 1 in 500 chance per year), the 2% annual chance flood (i.e. 1 in 50 chance per year), and the 10% annual chance flood (i.e. 1 in 10 chance per year). These unique flood scenarios are published in the flood profile of the Flood Insurance Study (volumes two through five). The distance between cross sections can be a few feet near bridges and up to half a mile on large river systems. The most accurate determination of the base flood elevation at any site is to interpolate the flood elevation from the cross section or plot the location on the profile.In coastal Puget Sound the engineering model uses transects that are surveyed perpendicular to the shoreline. The transect data can be found in the flood insurance study volume one. Coastal flood elevations are shown to only the nearest integer because a single transect is used to charaterize long stretchs of shoreline. The calculated transect elevation is shown in the "WSEL_REG" field to the nearest tenth of a foot but this precise value should only be used for design or letters of map change for locations directly crossed by the transect. Generally, FEMA does not map special flood hazard areas that have a drainage basin less than one square mile. The County has identified several locations with small drainage basins that can experience severe localized flooding and these are shown on the map as X zones or 0.2% annual chance flood areas. FEMA (the Federal Emergency Management Agency) uses FIRM (Flood Insurance Rate Map) data for the National Flood Insurance Program (NFIP). Once aspect of the NFIP is that the flood insurance is required for any building in the 1% annual chance floodplain that has a mortgage backed by the Federal government. The 2017 DFIRM (Digital Flood Insurance Rate Map) replaced the retired 1987 FEMA FIRMs for Pierce County, Washington. The FIRM is the basis for floodplain management, mitigation, and insurance activities for the National Flood Insurance Program (NFIP). The DFIRM Database presents the flood risk information depicted on the FIRM in a digital format suitable for use in electronic mapping applications. The DFIRM database is a subset of the Digital FIS database that serves to archive the information collected during the FIS. Flood insurance applications include enforcement of the mandatory purchase requirement of the Flood Disaster Protection Act, which "... requires the purchase of flood insurance by property owners who are being assisted by Federal programs or by Federally supervised, regulated or insured agencies or institutions in the acquisition or improvement of land facilities located or to be located in identified areas having special flood hazards, " Section 2 (b) (4) of the Flood Disaster Protection Act of 1973. In addition to the identification of Special Flood Hazard Areas (SFHAs), the risk zones shown on the FIRMs are the basis for the establishment of premium rates for flood coverage offered through the NFIP. DescriptionThis is 2017 DFIRM Data for cross section lines. New to the DFIRM data is the coastal flood study, that adds Velocity Zones (VE) along Puget Sound and the Seclusion Boundary. Seclusion areas are located where floodplains are affected by non-accredited levees and retain 1970s modeled flood hazards. These lines show the locations of channel surveys used to calculate flood elevations in the hydraulic models. The Cross Sections are also shown on the Flood Profiles in the Flood Insurance Study (FIS) report and can be used to cross reference the Flood Profiles to the planimetric depiction of the flood hazards. All cross sections for which a spatial location is available should be included in the S_XS table. The Cross Sections are lines generally extending from outside the floodplain, across the entire floodplain and out the other side. In this data set the cross sections have been trimmed to include only the areas show to be in a flood hazard area. Each cross section is represented by a line feature. The line has been split where the modeling shows a different base flood elevation than the stream center on the left or right bank (reference 2017 FIS Volume 2). The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event (Zones A & V), the 0.2-percent-annual- chance flood event (Zone X shaded), areas of undetermined flood risk (Zone X shaded) and areas of minimal flood risk (Zone X unshaded). The DFIRM Database is derived from Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). The file is georeferenced to earth's surface using the UTM projection and coordinate system. The specifications for the horizontal control of DFIRM data files are consistent with those required for mapping at a scale of 1:12,000.
This tells the story of cataclysmic outburst floods that shaped the landscape of the Pacific Northwest during the last ice age. With imagery, maps and video, this story map follows the devastating deluge of the Missoula floods as it tore across the landscape, from its origins in western Montana to its terminus at the Pacific Ocean. Sites along the Ice Age Floods National Geologic Trail are featured, with an emphasis on flood features in Washington State.
The Flood Insurance Rate Map (FIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal flood risk. The FIRM Database is derived from Flood Insurance Studies (FISs), previously published FIRMs, flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). This file is georeferenced to the Earth's surface using the Geographic Coordinate System (GCS) and North American Datum of 1983 (NSRS-2007).
FEMA Framework Basemap datasets comprise six of the seven FGDC themes of geospatial data that are used by most GIS applications (Note: the seventh framework theme, orthographic imagery, is packaged in a separate NFIP Metadata Profile): cadastral, geodetic control, governmental unit, transportation, general structures, hydrography (water areas & lines. These data include an encoding of the geographic extent of the features and a minimal number of attributes needed to identify and describe the features. (Source: Circular A16, p. 13)
The Floodplain Mapping/Redelineation study deliverables depict and quantify the flood risks for the study area. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual- chance flood event, and areas of minimal flood risk. The Floodplain Mapping/Redelineation flood risk boundaries are derived from the engineering information Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA).
Normally, any FIRM that has associated flood profiles has cross sections. The S_XS table contains information about cross section lines. These lines usually represent the locations of channel surveys performed for input into the hydraulic model used to calculate flood elevations. Sometimes cross sections are interpolated between surveyed cross sections using high accuracy elevation data. Depending on the zone designation (Zone AE, Zone A, etc.), these locations may be shown on Flood Profiles in the FIS report and can be used to cross reference the Flood Profiles to the planimetric depiction of the flood hazards. This information is used in the Floodway Data Tables in the FIS report, as well as on the FIRM panels.
This layer is a component of Region Preliminary Data.
The profile baseline shows the path of flood flows on the FIRM and is an accurate representation of the distance between cross sections, structures, nodes, or grids in the hydraulic model. The profile baseline is used for replicating the stationing and water-surface elevations found in the FIS report profiles, but in GIS format. This information is used in the following tables within the FIS report: Flooding Sources Included in this FIS report, Principal Flood Problems, Summary of Hydrologic and Hydraulic Analyses, Summary of Topographic Elevation Data Used in Mapping, the Stream-by_Stream Vertical Datum Conversion, and Summary of Contracted Studies Included in this FIS Report.
This layer is a component of Region Preliminary Data.
Historically, low-lying land adjacent to rivers and coastlines has been favoured for settlement as they provided sources of fresh water, food, transportation and waste disposal. These areas become affected by flooding during sufficiently heavy or prolonged rainfall, high tides or storm surges and cyclones. In the north-west of the State flooding is most likely to be caused by the summer monsoon or tropical cyclones while floods in the south-west are more likely to occur in response to heavy winter rainfalls. While historical flood records and information extend as far back as 1830, detailed information on peak flood levels is typically limited to the last few decades. This dataset shows the extent of flooding (polylines) that has occurred during major flood events in Western Australia. Note: To see the full scope of the historical flood mapping, 3 dataset layers are required to be loaded in the following order:
This data consists of a composite inundation hazards layer for counties from TX to ME, which have a flood exposure snapshot. The dataset was developed from a union of FEMA flood hazard, USACE hurricane evacuation study, NOAA sea level rise of 3-ft above MHHW, and NOAA Shallow Coastal flooding georeferenced digital data. The source and date have been preserved for each source dataset in the attribution. A unique identifier for each hazard, a total number of hazards and hazard description list in the attribution provide coastal risk exposure for each polygon
This layer is sourced from maps.coast.noaa.gov.
This map service presents spatial information developed as part of the National Oceanic and Atmospheric Administration (NOAA) Office for Coastal Management’s Coastal Flood Exposure Mapper. The purpose of the online mapping tool is to provide coastal managers, planners, and stakeholders a preliminary look at exposures to coastal flooding hazards. The Mapper is a screening-level tool that uses nationally consistent data sets and analyses. Data and maps provided can be used at several scales to help communities initiate resilience planning efforts. Currently the extent of the Coastal Flood Exposure Mapper covers U.S. coastal areas along the Gulf of Mexico and Atlantic Ocean. NOAA provides the information “as-is” and shall incur no responsibility or liability as to the completeness or accuracy of this information. NOAA assumes no responsibility arising from the use of this information. For additional information, please contact the NOAA Office for Coastal Management (coastal.info@noaa.gov).
© NOAA Office for Coastal Management
Location and attributes for hydrography features shown on FIRM as lines.
The S_Wtr_Ln table contains information about surface water linear features. The spatial elements representing surface water line features are lines. Normally stream centerlines will be represented as line features. However, the main purpose of the S_Wtr_Ar table and the S_Wtr_Ln table is to provide a cartographic depiction of the surface water features for visual interpretation of the mapping data. As a result, the method for structuring surface water features as lines or polygons is very flexible. Lake shorelines and stream channel banks used to show lakes and wide rivers may be represented as polygons. However, they may be represented as lines based on the structure of the data received and the mapping partner’s discretion. Surface water features may appear in either the S_Wtr_Ar table or the S_Wtr_Ln table or both. The hydrologic structure of the modeled stream network will be represented by the S_Profil_Basln layer. This information is used in the Transect Locator Map and the FIRM Panel Index in the FIS report, as well as the FIRM panels.
This layer is a component of Region Preliminary Data.
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Authoritative CBRS boundary locations are shown on maps administered by the U.S. Fish and Wildlife Service. Normally, these areas are already shown on existing FIRMs for the area. CBRS areas have restrictions on Federal funding (including flood insurance coverage) after specified dates for new or substantially improved structures. This information is needed for the Coastal Barrier Resources System Information table in the FIS report and for the FIRM panels.
This layer is a component of Region Preliminary Data.
The Flood Insurance Rate Map (FIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual-chance flood event, and areas of minimal flood risk. The FIRM Database is derived from Flood Insurance Studies (FISs), previously published FIRMs, flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). This file is georeferenced to the Earth's surface using the Geographic Coordinate System (GCS) and North American Datum of 1983.