78 datasets found
  1. g

    National Flood Hazard Layer (NFHL)

    • data.globalchange.gov
    • catalog.data.gov
    • +9more
    Updated Apr 3, 2015
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    (2015). National Flood Hazard Layer (NFHL) [Dataset]. https://data.globalchange.gov/dataset/fema-national-flood-hazard-layer-nfhl
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    Dataset updated
    Apr 3, 2015
    Description

    The National Flood Hazard Layer (NFHL) is a compilation of GIS data that comprises a nationwide digital Flood Insurance Rate Map. The GIS data and services are designed to provide the user with the ability to determine the flood zone, base flood elevation, and floodway status for a particular location. It also has information about the NFIP communities, map panels, cross sections, hydraulic structures, Coastal Barrier Resource System, and base maps such as road, stream, and public land survey data. Through flood studies, FEMA produces Flood Insurance Study Reports, FIRM Panels, and FIRM Databases. FIRM Databases that become effective are incorporated into the NFHL. Updates to the NFHL are issued through Letters of Map Revision (LOMRs) and Letters of Map Amendment (LOMAs). Continuously updated, the NFHL serves as a Digital Flood Insurance Rate Map representing the current effective flood data for those communities where maps have been digitized. NFHL data can be viewed with widely available GIS software, including freely available programs that work with GIS shapefiles. For more information on the NFHL, see the online resources referenced herein. Using base maps: The minimum horizontal positional accuracy for base map hydrographic and transportation features used with the NFHL is the NSSDA radial accuracy of 38 feet. Letter of Map Amendment (LOMA) point locations are approximate. The location of the LOMA is referenced in the legal description of the letter itself. LOMA points can be viewed in the NFHL Interactive Map on the FEMA GeoPlatform.

  2. g

    Flood Map for Planning (Rivers and Sea) - Flood Zone 2

    • gimi9.com
    • data.catchmentbasedapproach.org
    • +1more
    Updated Dec 14, 2024
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    (2024). Flood Map for Planning (Rivers and Sea) - Flood Zone 2 [Dataset]. https://gimi9.com/dataset/uk_flood-map-for-planning-rivers-and-sea-flood-zone-2
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    Dataset updated
    Dec 14, 2024
    License

    CC0 1.0 Universal Public Domain Dedicationhttps://creativecommons.org/publicdomain/zero/1.0/
    License information was derived automatically

    Description

    The Flood Map for Planning (Rivers and Sea) includes several layers of information. This dataset covers Flood Zone 2 and should not be used without Flood Zone 3. It is our best estimate of the areas of land at risk of flooding, when the presence of flood defences are ignored and covers land between Zone 3 and the extent of the flooding from rivers or the sea with a 1 in 1000 (0.1%) chance of flooding each year. This dataset also includes those areas defined in Flood Zone 3. This dataset is designed to support flood risk assessments in line with Planning Practice Guidance ; and raise awareness of the likelihood of flooding to encourage people living and working in areas prone to flooding to find out more and take appropriate action. The information provided is largely based on modelled data and is therefore indicative rather than specific. Locations may also be at risk from other sources of flooding, such as high groundwater levels, overland run off from heavy rain, or failure of infrastructure such as sewers and storm drains. The information indicates the flood risk to areas of land and is not sufficiently detailed to show whether an individual property is at risk of flooding, therefore properties may not always face the same chance of flooding as the areas that surround them. This is because we do not hold details about properties and their floor levels. Information on flood depth, speed or volume of flow is not included. NOTE: We have paused quarterly updates of this dataset. Please visit the “Pause to Updates of Flood Risk Maps” announcement on our support pages for further information. We will provide notifications on the Flood Map for Planning website to indicate where we have new flood risk information. Other data related to the Flood Map for Planning will continue to be updated, including data relating to flood history, flood defences, and water storage areas. Attribution statement: © Environment Agency copyright and/or database right 2023. All rights reserved. Some features of this map are based on digital spatial data from the Centre for Ecology & Hydrology, © NERC (CEH). © Crown Copyright and Database Rights 2023 OS AC0000807064.

  3. n

    FEMA National Flood Hazard Layer Viewer

    • data.gis.ny.gov
    Updated Mar 29, 2023
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    ShareGIS NY (2023). FEMA National Flood Hazard Layer Viewer [Dataset]. https://data.gis.ny.gov/datasets/fema-national-flood-hazard-layer-viewer
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    Dataset updated
    Mar 29, 2023
    Dataset authored and provided by
    ShareGIS NY
    Description

    The National Flood Hazard Layer (NFHL) is a geospatial database that contains current effective flood hazard data. FEMA provides the flood hazard data to support the National Flood Insurance Program. You can use the information to better understand your level of flood risk and type of flooding.The NFHL is made from effective flood maps and Letters of Map Change (LOMC) delivered to communities. NFHL digital data covers over 90 percent of the U.S. population. New and revised data is being added continuously. If you need information for areas not covered by the NFHL data, there may be other FEMA products which provide coverage for those areas.In the NFHL Viewer, you can use the address search or map navigation to locate an area of interest and the NFHL Print Tool to download and print a full Flood Insurance Rate Map (FIRM) or FIRMette (a smaller, printable version of a FIRM) where modernized data exists. Technical GIS users can also utilize a series of dedicated GIS web services that allow the NFHL database to be incorporated into websites and GIS applications. For more information on available services, go to the NFHL GIS Services User Guide.You can also use the address search on the FEMA Flood Map Service Center (MSC) to view the NFHL data or download a FIRMette. Using the “Search All Products” on the MSC, you can download the NFHL data for a County or State in a GIS file format. This data can be used in most GIS applications to perform spatial analyses and for integration into custom maps and reports. To do so, you will need GIS or mapping software that can read data in shapefile format.FEMA also offers a download of a KMZ (keyhole markup file zipped) file, which overlays the data in Google Earth™. For more information on using the data in Google Earth™, please see Using the National Flood Hazard Layer Web Map Service (WMS) in Google Earth™.

  4. USA Flood Hazard Areas

    • center-for-community-investment-lincolninstitute.hub.arcgis.com
    • gis-fema.hub.arcgis.com
    • +2more
    Updated Oct 3, 2018
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    Esri (2018). USA Flood Hazard Areas [Dataset]. https://center-for-community-investment-lincolninstitute.hub.arcgis.com/datasets/11955f1b47ec41a3af86650824e0c634
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    Dataset updated
    Oct 3, 2018
    Dataset authored and provided by
    Esrihttp://esri.com/
    Area covered
    Pacific Ocean, North Pacific Ocean
    Description

    The Federal Emergency Management Agency (FEMA) produces Flood Insurance Rate maps and identifies Special Flood Hazard Areas as part of the National Flood Insurance Program's floodplain management. Special Flood Hazard Areas have regulations that include the mandatory purchase of flood insurance for holders of federally regulated mortgages. In addition, this layer can help planners and firms avoid areas of flood risk and also avoid additional cost to carry insurance for certain planned activities.Dataset SummaryPhenomenon Mapped: Flood Hazard AreasGeographic Extent: Contiguous United States, Alaska, Hawaii, Puerto Rico, Guam, US Virgin Islands, Northern Mariana Islands and American Samoa.Projection: Web Mercator Auxiliary SphereData Coordinate System: USA Contiguous Albers Equal Area Conic USGS version (contiguous US, Puerto Rico, US Virgin Islands), WGS 1984 Albers (Alaska), Hawaii Albers Equal Area Conic (Hawaii), Western Pacific Albers Equal Area Conic (Guam, Northern Mariana Islands, and American Samoa)Cell Sizes: 10 meters (default), 30 meters, and 90 metersUnits: NoneSource Type: ThematicPixel Type: Unsigned integerSource: Federal Emergency Management Agency (FEMA)Update Frequency: AnnualPublication Date: December 18, 2024This layer is derived from the December 18, 2024 version Flood Insurance Rate Map feature class S_FLD_HAZ_AR. The vector data were then flagged with an index of 88 classes, representing a unique combination of values displayed by three renderers. (In three resolutions the three renderers make nine processing templates.) Repair Geometry was run on the set of features, then the features were rasterized using the 88 class index at a resolutions of 10, 30, and 90 meters, using the Polygon to Raster tool and the "MAXIMUM_COMBINED_AREA" option. Not every part of the United States is covered by flood rate maps. This layer compiles all the flood insurance maps available at the time of publication. To make analysis easier, areas that were NOT mapped by FEMA for flood insurance rates no longer are served as NODATA but are filled in with a value of 250, representing any unmapped areas which appear in the US Census' boundary of the USA states and territories. The attribute table corresponding to value 250 will indicate that the area was not mapped.What can you do with this layer?This layer is suitable for both visualization and analysis across the ArcGIS system. This layer can be combined with your data and other layers from the ArcGIS Living Atlas of the World in ArcGIS Online and ArcGIS Pro to create powerful web maps that can be used alone or in a story map or other application.Because this layer is part of the ArcGIS Living Atlas of the World it is easy to add to your map:In ArcGIS Online, you can add this layer to a map by selecting Add then Browse Living Atlas Layers. A window will open. Type "flood hazard areas" in the search box and browse to the layer. Select the layer then click Add to Map.In ArcGIS Pro, open a map and select Add Data from the Map Tab. Select Data at the top of the drop down menu. The Add Data dialog box will open on the left side of the box, expand Portal if necessary, then select Living Atlas. Type "flood hazard areas" in the search box, browse to the layer then click OK.In ArcGIS Pro you can use the built-in raster functions to create custom extracts of the data. Imagery layers provide fast, powerful inputs to geoprocessing tools, models, or Python scripts in Pro.The ArcGIS Living Atlas of the World provides an easy way to explore many other beautiful and authoritative maps on hundreds of topics like this one.Processing TemplatesCartographic Renderer - The default. These are meaningful classes grouped by FEMA which group its own Flood Zone Type and Subtype fields. This renderer uses FEMA's own cartographic interpretations of its flood zone and zone subtype fields to help you identify and assess risk. Flood Zone Type Renderer - Specifically renders FEMA FLD_ZONE (flood zone) attribute, which distinguishes the original, broadest categories of flood zones. This renderer displays high level categories of flood zones, and is less nuanced than the Cartographic Renderer. For example, a fld_zone value of X can either have moderate or low risk depending on location. This renderer will simply render fld_zone X as its own color without identifying "500 year" flood zones within that category.Flood Insurance Requirement Renderer - Shows Special Flood Hazard Area (SFHA) true-false status. This may be helpful if you want to show just the places where flood insurance is required. A value of True means flood insurance is mandatory in a majority of the area covered by each 10m pixel.Each of these three renderers have templates at three different raster resolutions depending on your analysis needs. To include the layer in web maps to serve maps and queries, the 10 meter renderers are the preferred option. These are served with overviews and render at all resolutions. However, when doing analysis of larger areas, we now offer two coarser resolutions of 30 and 90 meters in processing templates for added convenience and time savings.Questions?Please leave a comment below if you have a question about this layer, and we will get back to you as soon as possible.

  5. a

    Hazards Flood Zone

    • gis.data.alaska.gov
    • data1-msb.opendata.arcgis.com
    • +1more
    Updated Jan 22, 2020
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    Matanuska-Susitna Borough (2020). Hazards Flood Zone [Dataset]. https://gis.data.alaska.gov/maps/d2bd4dc185cc401da508188f03d07a70
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    Dataset updated
    Jan 22, 2020
    Dataset authored and provided by
    Matanuska-Susitna Borough
    Area covered
    Description

    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 State Plane 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.

  6. Historic Flood Map

    • environment.data.gov.uk
    • data.europa.eu
    Updated Feb 6, 2025
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    Environment Agency (2025). Historic Flood Map [Dataset]. https://environment.data.gov.uk/dataset/889885c0-d465-11e4-9507-f0def148f590
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    Dataset updated
    Feb 6, 2025
    Dataset authored and provided by
    Environment Agencyhttps://www.gov.uk/ea
    License

    Open Government Licence 3.0http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/
    License information was derived automatically

    Description

    The Historic Flood Map is a GIS layer showing the maximum extent of individual Recorded Flood Outlines from river, the sea and groundwater springs that meet a set criteria. It shows areas of land that have previously been subject to flooding in England. This excludes flooding from surface water, except in areas where it is impossible to determine whether the source is fluvial or surface water but the dominant source is fluvial.

    The majority of records began in 1946 when predecessor bodies to the Environment Agency started collecting detailed information about flooding incidents, although we hold limited details about flooding incidents prior to this date.

    If an area is not covered by the Historic Flood Map it does not mean that the area has never flooded, only that we do not currently have records of flooding in this area that meet the criteria for inclusion. It is also possible that the pattern of flooding in this area has changed and that this area would now flood or not flood under different circumstances. Outlines that don’t meet this criteria are stored in the Recorded Flood Outlines dataset.

    The Historic Flood Map takes into account the presence of defences, structures, and other infrastructure where they existed at the time of flooding. It will include flood extents that may have been affected by overtopping, breaches or blockages.

    Flooding is shown to the land and does not necessarily indicate that properties were flooded internally.

  7. n

    North Carolina Effective Flood Zones

    • nconemap.gov
    Updated May 6, 2019
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    State of North Carolina - Emergency Management (2019). North Carolina Effective Flood Zones [Dataset]. https://www.nconemap.gov/maps/a178aae74ee347d786e853e5a442eea2
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    Dataset updated
    May 6, 2019
    Dataset authored and provided by
    State of North Carolina - Emergency Management
    Area covered
    Description

    North Carolina Effective Flood zones: In 2000, the Federal Emergency Management Agency (FEMA) designated North Carolina a Cooperating Technical Partner State, formalizing an agreement between FEMA and the State to modernize flood maps. This partnership resulted in creation of the North Carolina Floodplain Mapping Program (NCFMP). As a CTS, the State assumed primary ownership and responsibility of the Flood Insurance Rate Maps (FIRMs) for all North Carolina communities as part of the National Flood Insurance Program (NFIP). This project includes conducting flood hazard analyses and producing updated, Digital Flood Insurance Rate Maps (DFIRMs). Floodplain management is a process that aims to achieve reduced losses due to flooding. It takes on many forms, but is realized through a series of federal, state, and local programs and regulations, in concert with industry practice, to identify flood risk, implement methods to protect man-made development from flooding, and protect the natural and beneficial functions of floodplains. FIRMs are the primary tool for state and local governments to mitigate areas of flooding. Individual county databases can be downloaded from https://fris.nc.gov Updated Jan 17th, 2025.

  8. n

    FEMA Flood Hazard Zones

    • opdgig.dos.ny.gov
    Updated Nov 9, 2022
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    New York State Department of State (2022). FEMA Flood Hazard Zones [Dataset]. https://opdgig.dos.ny.gov/datasets/NYSDOS::fema-flood-hazard-zones/about
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    Dataset updated
    Nov 9, 2022
    Dataset authored and provided by
    New York State Department of State
    Area covered
    Pacific Ocean, North Pacific Ocean
    Description

    This dataset displays the locations of flood hazard zones identified by FEMA. The Federal Emergency Management Agency (FEMA) produces Flood Insurance Rate maps and identifies Special Flood Hazard Areas as part of the National Flood Insurance Program's floodplain management. Special Flood Hazard Areas have regulations that include the mandatory purchase of flood insurance. This layer is derived from the October 13, 2021 version of the National Flood Hazard Layer feature class S_Fld_Haz_Ar. The data were aggregated into eight classes to produce the Esri Symbology field based on symbology provided by FEMA. All other layer attributes are derived from the National Flood Hazard Layer.The layer was projected to Web Mercator Auxiliary Sphere, then the repair geometry geoprocessing tool was run on it. Its resolution was set to 0.0001 meter. To improve performance Flood Zone values "Area Not Included", "Open Water", "D", "NP", and No Data were removed from the layer. Areas with Flood Zone value "X" subtype "Area of Minimal Flood Hazard" were also removed. An imagery layer created from this dataset provides access to the full set of records in the National Flood Hazard Layer.View Dataset on the Gateway

  9. c

    Flood Map for Planning (Rivers and Sea) - Flood Storage Areas

    • data.catchmentbasedapproach.org
    • environment.data.gov.uk
    Updated Jun 20, 2024
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    The Rivers Trust (2024). Flood Map for Planning (Rivers and Sea) - Flood Storage Areas [Dataset]. https://data.catchmentbasedapproach.org/items/045f12666adf4f32991680aeb64b0bb0
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    Dataset updated
    Jun 20, 2024
    Dataset authored and provided by
    The Rivers Trust
    Area covered
    Description

    The Flood Map for Planning (Rivers and Sea) includes several layers of information. This dataset covers Flood Storage Areas. It shows those areas that act as a balancing reservoir, storage basin or balancing pond. Their purpose is to attenuate an incoming flood peak to a flow level that can be accepted by the downstream channel. It may also delay the timing of a flood peak so that its volume is discharged over a longer time interval. We have assumed that flood storage areas act perfectly and give the same level of protection as when our assessment of the area was carried out. Flood storage areas do not completely remove the chance of flooding and can be overtopped or fail in extreme weather conditions.This dataset is designed to raise awareness of the likelihood of flooding and to encourage people living and working in areas prone to flooding to find out more and take appropriate action.

  10. a

    Find My Flood Zone

    • hub.arcgis.com
    Updated Jul 10, 2019
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    Lee County Florida GIS (2019). Find My Flood Zone [Dataset]. https://hub.arcgis.com/maps/dd2e6827262b404f93eaff8348a8ede2
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    Dataset updated
    Jul 10, 2019
    Dataset authored and provided by
    Lee County Florida GIS
    Area covered
    Description

    Find my Flood Zone provides current flood information from FEMA's Flood Insurance Rate Map (FIRM) for unincorporated Lee County, City of Fort Myers and Town of Fort Myers Beach. While flood zones are depicted for the entire county, residents should contact their local jurisdictions to verify their current flood zone.

  11. FEMA's National Flood Hazard Layer ND

    • hub.arcgis.com
    • disasters.amerigeoss.org
    Updated Sep 24, 2018
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    FEMA (2018). FEMA's National Flood Hazard Layer ND [Dataset]. https://hub.arcgis.com/maps/FEMA::femas-national-flood-hazard-layer-nd
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    Dataset updated
    Sep 24, 2018
    Dataset provided by
    Federal Emergency Management Agencyhttp://www.fema.gov/
    Authors
    FEMA
    Area covered
    Description

    On January 25, 2018 FEMA replaced this map with a new NFHL map with additional functionality which allows users to print official flood maps. On April 1, 2018 this map and NFHL link will no longer function. Please update your bookmark to https://hazards-fema.maps.arcgis.com/apps/webappviewer/index.html?id=8b0adb51996444d4879338b5529aa9cd. For more information on NFHL data availability, please visit the NFHL GIS Services page at https://hazards.fema.gov/femaportal/wps/portal/NFHLWMSAs of August 1, 2017 all FEMA systems will require the use of the “https” protocol, and “http” links will no longer function. This may impact NFHL web services. The FEMA GeoPlatform (including this map) will not be affected by this change. For more information on how NFHL GIS services will be impacted, please visit the NFHL GIS Services page at https://hazards.fema.gov/femaportal/wps/portal/NFHLWMS.An NFHL FIRMette print service is now available HERE. (For a video tutorial, click here.)OverviewThe National Flood Hazard Layer (NFHL) dataset represents the current effective flood data for the country, where maps have been modernized. It is a compilation of effective Flood Insurance Rate Map (FIRM) databases and Letters of Map Change (LOMCs). The NFHL is updated as studies go effective. For more information, visit FEMA's Map Service Center (MSC). Base Map ConsiderationsThe default base map is from a USGS service and conforms to FEMA's specification for horizontal accuracy. This base map from The National Map (TNM) consists of National Agriculture Imagery Program (NAIP) and high resolution orthoimagery (HRO) that combine the visual attributes of an aerial photograph with the spatial accuracy and reliability of a map. This map should be considered the best online resource to use for official National Flood Insurance Program (NFIP) purposes when determining locations in relation to regulatory flood hazard information. If a different base map is used with the NFHL, the accuracy specification may not be met and the resulting map should be used for general reference only, and not official NFIP purposes. Users can download a simplified base map from the USGS service via: https://viewer.nationalmap.gov/services/ For the specifics of FEMA’s policy on the use of digital flood hazard data for NFIP purposes see: http://www.fema.gov/library/viewRecord.do?id=3235Letter of Map Amendment (LOMA) pointsLOMA point locations are approximate. The location of the LOMA is referenced in the legal description of the letter itself. Click the LOMA point for a link to the letter (use the arrows at the top of the popup window to bring up the LOMA info, if needed).This LOMA database may include LOMAs that are no longer effective. To be certain a particular LOMA is currently valid, please check relevant documentation at https://msc.fema.gov/ . Relevant documents can be found for a particular community by choosing to "Search All Products", and finding the community by State and County. Documents include LOMAs found in the "Effective Products" and "LOMC" folders, as well as Revalidations (those LOMAs which are still considered to be effective after a map is revised).Updates3/27/2017 - Updated all references to https to prevent issues with mixed content.5/11/2016 - Added link to NFHL FIRMette Print Service. Updated LOMA and CBRS popup notes.2/20/2014 - Created a General Reference map for use when the USGS base map service is down. Renamed this map to "Official".Further InformationSpecific questions about FEMA flood maps can be directed to FEMAMapSpecialist@riskmapcds.comFor more flood map data, tool, and viewing options, visit the FEMA NFHL page. Information about connecting to web map services (REST, WMS, WFS) can be found here.Several fact sheets are available to help you learn more about FEMA’s NFHL utility: National Flood Hazard Layer (NFHL) GIS Services Users GuideNational Flood Hazard Layer (NFHL): New Products and Services for FEMA's Flood Hazard Map DataMoving to Digital Flood Hazard Information Standards for Flood Risk Analysis and MappingNFHL GIS Data: Perform Spatial Analyses and Make Custom Maps and Reports

  12. d

    National Flood Hazard - Cross Sections

    • catalog.data.gov
    • data.lojic.org
    • +4more
    Updated Apr 13, 2023
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    Louisville/Jefferson County Information Consortium (2023). National Flood Hazard - Cross Sections [Dataset]. https://catalog.data.gov/dataset/national-flood-hazard-cross-sections-b1254
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    Dataset updated
    Apr 13, 2023
    Dataset provided by
    Louisville/Jefferson County Information Consortium
    Description

    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.Flood hazard and supporting data are developed using specifications for horizontal control consistent with 1:12,000–scale mapping. If you plan to display maps from the National Flood Hazard Layer with other map data for official purposes, ensure that the other information meets FEMA’s standards for map accuracy.The minimum horizontal positional accuracy for base map hydrographic and transportation features used with the NFHL is the NSSDA radial accuracy of 38 feet. USGS imagery and map services that meet this standard can be found by visiting the Knowledge Sharing Site (KSS) for Base Map Standards (420). Other base map standards can be found athttps://riskmapportal.msc.fema.gov/kss/MapChanges/default.aspx. You will need a username and password to access this information.The NFHL data are from FEMA’s Flood Insurance Rate Map (FIRM) databases. New data are added continually. The NFHL also contains map changes to FIRM data made by Letters of Map Revision (LOMRs).The NFHL is stored in North American Datum of 1983, Geodetic Reference System 80 coordinate system, though many of the NFHL GIS web services support the Web Mercator Sphere projection commonly used in web mapping applications.

  13. e

    Flood Map: Flood Zone 2

    • data.europa.eu
    Updated Feb 1, 2001
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    Natural Resources Wales (2001). Flood Map: Flood Zone 2 [Dataset]. https://data.europa.eu/data/datasets/flood-map-flood-zone-2223?locale=en
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    Dataset updated
    Feb 1, 2001
    Dataset authored and provided by
    Natural Resources Wales
    Description

    This dataset has been discontinued. New Flood Zones will be available when the new Flood Map for Planning is published at the end of Summer 2021. Flood Map shows the areas across Wales that could be affected by flooding from rivers or the sea. It also shows flood defences and the areas that benefit from them. Flood Map is designed to raise awareness among the public local authorities and other organisations of the likelihood of flooding and to encourage people living and working in areas prone to flooding to find out more and take appropriate action. The Flood Map includes several layers of information, this layer is: Flood Zone 2, which is NRWs best estimate of the areas of land between Zone 3 and the extent of the flood from rivers or the sea with a 1000 to 1 chance of flooding in any year. It includes those areas defined in Flood Zone 3.

  14. D

    FEMA FIRM Flood Hazards (Coastal) - 2021 Update

    • data.sfgov.org
    Updated Jan 12, 2021
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    FEMA FIRM Flood Hazards (Coastal) - 2021 Update [Dataset]. https://data.sfgov.org/Energy-and-Environment/FEMA-FIRM-Flood-Hazards-Coastal-2021-Update/jyce-e25k
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    tsv, csv, application/rssxml, application/rdfxml, xml, kml, application/geo+json, kmzAvailable download formats
    Dataset updated
    Jan 12, 2021
    Description

    A) This data describes the Special Flood Hazard Areas (SFHA's) pursuant to the Federal Emergency Management Agency's (FEMA's) Flood Insurance Rate Map (FIRM) for the City and County of San Francisco.

    B) These map products were created by FEMA and you can find more information on their creation on the following page: https://www.fema.gov/flood-maps/products-tools/products

    C) These maps are updated periodically in light of new information if flooding conditions change for a jurisdiction. This occurs on an as needed basis and is coordinated through the

    D) In order to use this dataset it is important to know what each zone designation means. You can find these designations below -- Zone AE, AO, and VE (AREAS WITH HIGH FLOOD RISK (SPECIAL FLOOD HAZARD AREAS; REGULATIONS APPLY): Properties within SFHAs are subject to flooding during the 1-percent-chance flood, a flood with a 1 percent chance of occurrence in any given year (also referred to as the Base Flood or 100-year flood).

    Zone D (AREA OF UNDETERMINED FLOOD RISK): In San Francisco, Zone D is an area of possible, but undefined, flood risk for waterfront piers operated by the Port of San Francisco.

    Zone X Shaded or Unshaded (AREA OF LOW OR MINIMAL FLOOD RISK): "Shaded" Zone X represents areas of moderate or low flood risk – these areas are subject to inundation during a flood having a 0.2-percent-annual-chance of occurrence, or during the 1-percent-annual-chance flood with depth less than 1 foot. "Unshaded" Zone X represents areas of minimal flood risk or areas that FEMA did not study or map.

    E) For regulatory implications of map, see: https://onesanfrancisco.org/San-Francisco-Floodplain-Management-Program

    For more detailed information on specific properties impacted by FIRM Map, see: https://sfplanninggis.org/PIM/

  15. a

    FEMA 100 Year Flood Plain

    • data-deschutes.opendata.arcgis.com
    • data.deschutes.org
    • +1more
    Updated Jun 4, 2021
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    Deschutes County (2021). FEMA 100 Year Flood Plain [Dataset]. https://data-deschutes.opendata.arcgis.com/items/e94cecc049bd43e5a77977b9ca787fc2
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    Dataset updated
    Jun 4, 2021
    Dataset authored and provided by
    Deschutes County
    Area covered
    Description

    Federal Emergency Management Agency Floodplain for Deschutes County, Oregon. Updated by FEMA nationwide in 2007, the FIRM is the basis for floodplain management, mitigation, and insurance activities for the National Flood Insurance Program (NFIP). 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 1973 Flood Disaster Protection Act). 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 insurance coverage offered through the NFIP. Q3 Flood Data files convey certain key features from the existing hard copy FIRM. Edge-matching errors, overlaps and deficiencies in coverage, and similar problems are not corrected during digitizing or post-processing. The Q3 Flood Data files are intended to provide users with automated flood risk data that may be used to locate SFHAs. More detailed information may be obtained from the paper FIRM.

  16. a

    Flood Zone Map (PA DCED)

    • data-dauphinco.opendata.arcgis.com
    • hub.arcgis.com
    Updated Sep 12, 2018
    + more versions
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    Dauphin County, PA (2018). Flood Zone Map (PA DCED) [Dataset]. https://data-dauphinco.opendata.arcgis.com/documents/3df7effce91643d1bc6f5f7e20a45087
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    Dataset updated
    Sep 12, 2018
    Dataset authored and provided by
    Dauphin County, PA
    Area covered
    Pennsylvania
    Description

    The Pennsylvania Flood Risk Tool is an interactive web map application developed by Penn State University with funding from the Federal Emergency Management Agency (FEMA). This application depicts 1% annual chance floodplain boundaries in an online map environment. https://pafloodrisk.psu.edu/home/index.html

  17. g

    Coastal Flood Maps (FRM_FH_COASTAL_DATA_NOT_AVAILABLE_M_CC)

    • find.data.gov.scot
    • spatialdata.gov.scot
    • +1more
    html, zip
    Updated Mar 25, 2024
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    (2024). Coastal Flood Maps (FRM_FH_COASTAL_DATA_NOT_AVAILABLE_M_CC) [Dataset]. https://find.data.gov.scot/datasets/40497
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    zip(null MB), html(null MB)Available download formats
    Dataset updated
    Mar 25, 2024
    Area covered
    Scotland
    Description

    There are a small number of locations for which suitable future flood map data is not available. These locations are identified using the Future FRM_FH_COASTAL_DATA_NOT_AVAILABLE_M_CC. Data for the present day flood maps will still be available in these areas. The lack of future flood map data in these locations does not indicate that there is no future flood risk.

  18. s

    Flood Hazard Areas - 1% Annual Chance

    • data.stlouisco.com
    • hub.arcgis.com
    • +3more
    Updated Jul 8, 2015
    + more versions
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    Saint Louis County GIS Service Center (2015). Flood Hazard Areas - 1% Annual Chance [Dataset]. https://data.stlouisco.com/maps/2082093545ed4f9589236a5ce9bcc36c
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    Dataset updated
    Jul 8, 2015
    Dataset authored and provided by
    Saint Louis County GIS Service Center
    Area covered
    Description

    Open Data. Flood Hazard Areas in St. Louis County, Missouri. Flood Hazard Areas defined by FEMA as 1% annual chance of flooding and 26% chance over the life of a 30-year mortgage. These data were officially adopted by FEMA as of February 2015. Link to Metadata.

  19. d

    MD iMAP: Preliminary FEMA Floodplain

    • catalog.data.gov
    • opendata.maryland.gov
    • +1more
    Updated Jul 23, 2021
    + more versions
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    opendata.maryland.gov (2021). MD iMAP: Preliminary FEMA Floodplain [Dataset]. https://catalog.data.gov/dataset/md-imap-preliminary-fema-floodplain
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    Dataset updated
    Jul 23, 2021
    Dataset provided by
    opendata.maryland.gov
    Area covered
    Maryland
    Description

    This is a MD iMAP hosted service. Find more information on http://imap.maryland.gov. The DFIRM Database presents the flood risk information depicted on a given Flood Insurance Rate Map (FIRM) in a digital format suitable for use in electronic mapping applications. The DFIRM database is a subset of the Digital Flood Insurance Study (FIS) database that serves to archive the information collected during the FIS. This map service is a composite of Effective and Preliminary floodplain data. Q3 data is used where neither Effective or Preliminary data is available for a given community. 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 specifications for the horizontal control of DFIRM data files are consistent with those required for mapping at a scale of 1:12 - 000. Last Updated: 03/2016 Map Service Link: http://geodata.md.gov/imap/rest/services/Hydrology/MD_Floodplain/FeatureServer ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively "the Data") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in the metadata.

  20. K

    Kerrville, Texas FEMA Flood Way

    • koordinates.com
    csv, dwg, geodatabase +6
    Updated Aug 31, 2018
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    City of Kerrville, Texas (2018). Kerrville, Texas FEMA Flood Way [Dataset]. https://koordinates.com/layer/20298-kerrville-texas-fema-flood-way/
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    dwg, mapinfo mif, geodatabase, kml, mapinfo tab, geopackage / sqlite, csv, shapefile, pdfAvailable download formats
    Dataset updated
    Aug 31, 2018
    Dataset authored and provided by
    City of Kerrville, Texas
    Area covered
    Description

    This layer shows the flood zones as defined by FEMA.

    © FEMA This layer is a component of Parcel Viewer.

    This map document contains the parcel boundaries for Kerr County, Texas. The property ID number can be used to find more information about a parcel at the Kerr CAD website.

    This map document also includes the municipal boundaries, extraterritorial jurisdiction, and FEMA floodplains for reference.

    © Kerr Central Appraisal District, City of Kerrville, Texas, FEMA

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(2015). National Flood Hazard Layer (NFHL) [Dataset]. https://data.globalchange.gov/dataset/fema-national-flood-hazard-layer-nfhl

National Flood Hazard Layer (NFHL)

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Dataset updated
Apr 3, 2015
Description

The National Flood Hazard Layer (NFHL) is a compilation of GIS data that comprises a nationwide digital Flood Insurance Rate Map. The GIS data and services are designed to provide the user with the ability to determine the flood zone, base flood elevation, and floodway status for a particular location. It also has information about the NFIP communities, map panels, cross sections, hydraulic structures, Coastal Barrier Resource System, and base maps such as road, stream, and public land survey data. Through flood studies, FEMA produces Flood Insurance Study Reports, FIRM Panels, and FIRM Databases. FIRM Databases that become effective are incorporated into the NFHL. Updates to the NFHL are issued through Letters of Map Revision (LOMRs) and Letters of Map Amendment (LOMAs). Continuously updated, the NFHL serves as a Digital Flood Insurance Rate Map representing the current effective flood data for those communities where maps have been digitized. NFHL data can be viewed with widely available GIS software, including freely available programs that work with GIS shapefiles. For more information on the NFHL, see the online resources referenced herein. Using base maps: The minimum horizontal positional accuracy for base map hydrographic and transportation features used with the NFHL is the NSSDA radial accuracy of 38 feet. Letter of Map Amendment (LOMA) point locations are approximate. The location of the LOMA is referenced in the legal description of the letter itself. LOMA points can be viewed in the NFHL Interactive Map on the FEMA GeoPlatform.

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