National Flood Hazard Layer (NFHL)


Identification Information:
Citation:
Citation Information:
Originator: Federal Emergency Management Agency
Publication Date: 20150130
Title: National Flood Hazard Layer (NFHL)
Edition: Version 1.1.1.0
Geospatial Data Presentation Form: FEMA-NFHL
Publication Information:
Publication Place: Washington, D.C.
Publisher: Federal Emergency Management Agency
Description:
Abstract: 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.
Purpose: 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 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. The FIRM Database presents the flood risk information depicted on the FIRM in a digital format suitable for use in electronic mapping applications. The FIRM Database serves to archive the information collected during the Flood Risk Project.
Time Period of Content:
Time Period Information:
Single Date/Time:
Calendar Date: 20141229
Currentness Reference: Publication Date
Status:
Progress: In work
Maintenance and Update Frequency: Monthly
Spatial Domain:
Bounding Coordinates:
West Bounding Coordinate: -172
East Bounding Coordinate: 147
North Bounding Coordinate: 72
South Bounding Coordinate: -15
Keywords:
Theme:
Theme Keyword Thesaurus: NGDA Portfolio Themes
Theme Keyword: NGDA
Theme Keyword: National Geospatial Data Asset
Theme Keyword: Elevation Theme
Theme:
Theme Keyword Thesaurus: ISO 19115 Topic Category
Theme Keyword: hydrology
Theme Keyword: environment
Theme Keyword: inlandWaters
Theme Keyword: structure
Theme Keyword: transportation
Theme Keyword: elevation
Theme:
Theme Keyword Thesaurus: FEMA NFIP Topic Category
Theme Keyword: FIRM
Theme Keyword: FEMA Flood Hazard Zone
Theme Keyword: FIRM Database
Theme Keyword: Special Flood Hazard Area
Theme Keyword: Flood Insurance Rate Map
Theme Keyword: CBRS
Theme Keyword: Coastal Barrier Resources System
Theme Keyword: Riverine Flooding
Theme Keyword: Coastal Flooding
Theme Keyword: NFIP
Theme Keyword: Base Flood Elevation
Theme Keyword: SFHA
Theme Keyword: Floodway
Place:
Place Keyword Thesaurus: None
Place Keyword: Alabama
Place Keyword: Alaska
Place Keyword: American Samoa
Place Keyword: Arizona
Place Keyword: Arkansas
Place Keyword: California
Place Keyword: Colorado
Place Keyword: Connecticut
Place Keyword: Delaware
Place Keyword: District of Columbia
Place Keyword: Federated State of Micronesia
Place Keyword: Florida
Place Keyword: Georgia
Place Keyword: Guam
Place Keyword: Hawaii
Place Keyword: Idaho
Place Keyword: Illinois
Place Keyword: Indiana
Place Keyword: Iowa
Place Keyword: Kansas
Place Keyword: Kentucky
Place Keyword: Louisiana
Place Keyword: Maine
Place Keyword: Marshall Islands
Place Keyword: Maryland
Place Keyword: Massachusetts
Place Keyword: Michigan
Place Keyword: Minnesota
Place Keyword: Mississippi
Place Keyword: Missouri
Place Keyword: Montana
Place Keyword: Nebraska
Place Keyword: Nevada
Place Keyword: New Hampshire
Place Keyword: New Jersey
Place Keyword: New Mexico
Place Keyword: New York
Place Keyword: North Carolina
Place Keyword: North Dakota
Place Keyword: Northern Mariana Islands
Place Keyword: Ohio
Place Keyword: Oklahoma
Place Keyword: Oregon
Place Keyword: Palau
Place Keyword: Pennsylvania
Place Keyword: Puerto Rico
Place Keyword: Rhode Island
Place Keyword: South Carolina
Place Keyword: South Dakota
Place Keyword: Tennessee
Place Keyword: Texas
Place Keyword: Utah
Place Keyword: Vermont
Place Keyword: U.S. Minor Islands
Place Keyword: Virgin Islands
Place Keyword: Virginia
Place Keyword: Washington
Place Keyword: West Virginia
Place Keyword: Wisconsin
Place Keyword: Wyoming
Access Constraints: None
Use Constraints: The hardcopy FIRM and FIRM Database and the accompanying FIS are the official designation of SFHAs and Base Flood Elevations (BFEs) for the NFIP. For the purposes of the NFIP, changes to the flood risk information published by FEMA may only be performed by FEMA and through the mechanisms established in the NFIP regulations (44 CFR Parts 59-78). These digital data are produced in conjunction with the hardcopy FIRMs and generally match the hardcopy map exactly. Acknowledgement of FEMA would be appreciated in products derived from these data.
Point of Contact:
Contact Information:
Contact Organization Primary:
Contact Organization: Federal Emergency Management Agency
Contact Address:
Address Type: mailing
Address: 500 C Street, S.W.
City: Washington
State or Province: District of Columbia
Postal Code: 20472
Country: USA
Contact Voice Telephone: 1-877-336-2627
Contact Electronic Mail Address: FEMAMapSpecialist@riskmapcds.com
Native Data Set Environment: Original data development environment may vary. Finishing of the data is done using Esri's ArcGIS software. The geodatabase was created using ArcGIS version 10.1.
Data Quality Information:
Attribute Value Accuracy Information:
Attribute Accuracy Report: The NFHL incorporates all FIRM Databases published by FEMA and any LOMRs that have been issued against those databases since their publication date. The NFHL consists of vector files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The published effective FIRM and FIRM Database are issued as the official designation of the SFHAs. As such they are adopted by local communities and form the basis for administration of the NFIP. For these purposes they are authoritative. Provisions exist in the regulations for public review, appeals and corrections of the flood risk information shown to better match real world conditions. As with any engineering analysis of this type, variation from the estimated flood heights and floodplain boundaries is possible. Details of FEMA's requirements for the FISs and flood mapping process that produces these data are available in the Guidelines and Standards for Flood Risk Analysis and Mapping. Attribute accuracy was tested by manual comparison of source graphics with hardcopy plots and a symbolized display on an interactive computer graphic system. Independent quality control testing of the individual FIRM Database components of the NFHL was also performed. To obtain more detailed information in areas where Base Flood Elevations (BFEs) and/or floodways have been determined, users are encouraged to consult the Flood Profiles and Floodway Data and/or Summary of Stillwater Elevations tables contained within the FIS reports that accompany the individual FIRM Database components of the NFHL. Users should be aware that BFEs shown in the S_BFE table may represent rounded whole-foot elevations. These BFEs are intended for flood insurance rating purposes only and should not be used as the sole source of flood elevation information. Accordingly, flood elevation data presented in the FIS report must be used in conjunction with the FIRM for purposes of construction and/or floodplain management. The 1-percent-annual-chance water-surface elevations shown in the S_XS table match the regulatory elevations shown in the FIS report.
Logical Consistency Report: When FEMA revises an FIS, adjacent studies are checked to ensure agreement between flood elevations at the boundaries. Likewise flood elevations at the confluence of streams studied independently are checked to ensure agreement at the confluence. The FIRM and the FIS are developed together and care is taken to ensure that the elevations and other features shown on the flood profiles in the FIS agree with the information shown on the FIRM. However, the elevations as shown on the FIRM may represent rounded whole-foot elevations. They must be shown so that a profile recreated from the elevations on the FIRM will match the FIS profiles within one half of one foot.
Completeness Report: Data contained in the NFHL reflects the content of the source materials. Features may have been eliminated or generalized on the source graphic, due to scale and legibility constraints. With new mapping, FEMA plans to maintain full detail in the spatial data it produces. However, older information is often transferred from existing maps where some generalization has taken place. Flood risk data are developed for communities participating in the NFIP for use in insurance rating and for floodplain management. Flood hazard areas are determined using statistical analyses of records of river flow, storm tides, and rainfall; information obtained through consultation with the communities; floodplain topographic surveys; and hydrological and hydraulic analysis. Generally, regulatory water surface elevations and/or regulatory floodways are published only for developed or developing areas of communities. For areas where little or no development is expected to occur, FEMA may generate flood risk data without published water surface elevations. Typically, only drainage areas that are greater than one square mile and with an average of one foot of flood depth or greater are studied. Note: The NFHL reflects the most current information available when the distribution data set was created. Currently, not all areas of a State or Territory have effective FIRM Database data. As a result, users may need to refer to the effective FIRM for effective flood hazard information.
Positional Accuracy:
Horizontal Positional Accuracy:
Horizontal Positional Accuracy Report: The NFHL consists of vector files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The published effective FIRM and FIRM Database are issued as the official designation of the SFHAs. As such they are adopted by local communities and form the basis for administration of the NFIP. For these purposes they are authoritative. Provisions exist in the regulations for public review, appeals and corrections of the flood risk information shown to better match real world conditions. As with any engineering analysis of this type, variation from the estimated flood heights and floodplain boundaries is possible. Details of FEMA's requirements for the FISs and flood mapping process that produces these data are available in the Guidelines and Standards for Flood Risk Analysis and Mapping. Horizontal accuracy was tested by manual comparison of source graphics with hardcopy plots and a symbolized display on an interactive computer graphic system. Independent quality control testing of the individual FIRM Database components of the NFHL was also performed.
Vertical Positional Accuracy:
Vertical Positional Accuracy Report: The NFHL consists of vector files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The published effective FIRM and FIRM Database are issued as the official designation of the SFHAs. As such they are adopted by local communities and form the basis for administration of the NFIP. For these purposes they are authoritative. Provisions exist in the regulations for public review, appeals and corrections of the flood risk information shown to better match real world conditions. As with any engineering analysis of this type, variation from the estimated flood heights and floodplain boundaries is possible. Details of FEMA's requirements for the FISs and flood mapping process that produces these data are available in the Guidelines and Standards for Flood Risk Analysis and Mapping. The reliability of the floodplain boundary delineation is quantified by comparing the computed flood elevation to the ground elevation at the mapped floodplain boundary. The tolerance for how precisely the flood elevation and the ground elevation must match varies based on the flood risk class, which is a function of population, population density, and/or anticipated growth in floodplain areas. A horizontal accuracy of +/- 38 feet is used to determine the compliance with the vertical tolerances defined for each risk class. The range of differences between the ground elevation (defined from the topographic data used for the Flood Risk Project) and the computed flood elevation is between +/- 1.0 foot at the 95% confidence interval for areas with high population within the floodplain and/or high anticipated growth and Special Flood Hazard Areas (SFHAs) with high flood risk to +/- one-half the contour interval at the 85% confidence interval for areas with low population and densities within the floodplain and small or no anticipated growth and SFHAs with low flood risk. Independent quality control testing of the individual FIRM Database components of the NFHL was also performed.
Lineage:
Process Step:
Process Description: The NFHL dataset is a compilation of effective FIRM Databases (a collection of the digital data that are used in GIS systems for creating new Flood Insurance Rate Maps) and Letters of Map Change (Letters of Map Amendment and Letters of Map Revision only) that create a seamless GIS data layer for a State or Territory. It is updated on a monthly basis. The FIRM Databases are compiled in conjunction with the hardcopy FIRMs and the final FIS reports. The specifics of the hydrologic and hydraulic analyses performed are detailed in the FIS reports available for each jurisdiction. The results of these studies are submitted in digital format to FEMA. These data and unrevised data from effective FIRMs are compiled onto the base map used for FIRM publication and checked for accuracy and compliance with FEMA standards. As new FIRM Databases are received the individual FIRM layers are sewn into the nationwide layers of the NFHL. LOMRs for the FIRM Databases in the NFHL are cut directly into the NFHL data layers as they are being produced and finalized.
Process Date: 20150130
Spatial Reference Information:
Horizontal Coordinate System Definition:
Geographic:
Latitude Resolution: 1.3096e-009
Longitude Resolution: 1.3096e-009
Geographic Coordinate Units: Decimal degrees
Geodetic Model:
Horizontal Datum Name: North American Datum of 1983
Ellipsoid Name: Geodetic Reference System 80
Semi-major Axis: 6378137.0
Denominator of Flattening Ratio: 298.257222101
Vertical Coordinate System Definition:
Altitude System Definition:
Altitude Datum Name: North American Vertical Datum of 1988 and National Geodetic Vertical Datum of 1929
Altitude Resolution: 0.03
Altitude Units: feet
Altitude Encoding Method: Attribute values
Entity and Attribute Information:
Detailed Description:
Entity Type:
Entity Type Label: S_Alluvial_Fan
Entity Type Definition: Location and attributes for alluvial fan areas shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Base_Index
Entity Type Definition: Location and attributes for a tiling index for raster data used for the FIRM base map.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_BFE
Entity Type Definition: Location and attributes for base flood elevations lines shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_CBRS
Entity Type Definition: Location and attributes for Coastal Barrier Resource System units shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Cst_Gage
Entity Type Definition: Location and attributes for the coastal gages for the study area.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Cst_Tsct_Ln
Entity Type Definition: Location and attributes for coastal transect lines shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Datum_Conv_Pt
Entity Type Definition: Location and attributes for points used to calculate vertical datum conversion factors.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_FIRM_Pan
Entity Type Definition: Location and attributes for FIRM hardcopy map panels.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Fld_Haz_Ar
Entity Type Definition: Location and attributes flood insurance risk zones shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Fld_Haz_Ln
Entity Type Definition: Location and attributes for boundaries of flood insurance risk zones shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Gage
Entity Type Definition: Location and attributes for riverine gages used to determine discharges for the study area.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Gen_Struct
Entity Type Definition: Location and attributes for flood control structures shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_HWM
Entity Type Definition: Location and attributes for historic high water marks for the study area.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Hydro_Reach
Entity Type Definition: Location and attributes for lines that represent the connectivity between the subbasins and flow direction between nodes within the study area.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Label_Ld
Entity Type Definition: Location and attributes for leader lines for labels shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Label_Pt
Entity Type Definition: Location and attributes for labels shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Levee
Entity Type Definition: A spatial dataset consisting of lines that represent the centerlines of levees.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_LiMWA
Entity Type Definition: A spatial data set consisting of lines that depict the limit of 18-inch or greater coastal waves in a Coastal AE Zone.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_LOMR
Entity Type Definition: A spatial data set consisting of polygons that depict effective LOMRs that have been incorporated into the NFHL since the last publication of the FIRM panel for the area.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Nodes
Entity Type Definition: Location and attributes of points that depict locations of computed discharges for the 10-, 2-, 1-, and 0.2-percent-annual-chance floods.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_PFD_Ln
Entity Type Definition: Location and attributes for the primary frontal dune features for the coastal study area.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_PLSS_Ar
Entity Type Definition: Location and attributes of sections, townships and ranges shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Pol_Ar
Entity Type Definition: Location and attributes for political jurisdictions shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Profil_BasLn
Entity Type Definition: A spatial data set consisting of lines showing the flow path used for floodplain modeling and mapping.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Riv_Mrk
Entity Type Definition: Location and attributes for river mile markers shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Stn_Start
Entity Type Definition: A spatial data set consisting of points indicating the location of the reference point that was used as the origin for distance measurements along streams and rivers.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Subbasins
Entity Type Definition: Location and attributes for subbasins used in the hydrologic analysis.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Submittal_Info
Entity Type Definition: A spatial data set consisting of polygons depicting the extents of the studied area.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Topo_Confidence
Entity Type Definition: A spatial dataset consisting of polygons depicting areas of low confidence topographic data.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Trnsport_Ln
Entity Type Definition: Location and attributes for roads, railroads and other transportation features shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Tsct_Basln
Entity Type Definition: A spatial data set consisting of lines that represent the 0.0-foot elevation contour used for coastal modeling and mapping.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Wtr_Ar
Entity Type Definition: Location and attributes for hydrography features shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_Wtr_Ln
Entity Type Definition: Location and attributes for hydrography features shown on the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Detailed Description:
Entity Type:
Entity Type Label: S_XS
Entity Type Definition: Location and attributes for cross-section lines in the area covered by the FIRM.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available in the FEMA Library at http://www.fema.gov/media-library/assets/documents/34519).
Overview Description:
Entity and Attribute Overview: The NFHL is made up of several data themes containing both spatial and attribute information. These data together represent the current flood risk for the subject area as identified by FEMA. The attribute tables include SFHA locations, flood zone designations, BFEs, political entities, cross-section locations, FIRM panel information, and other data related to the NFIP.
Entity and Attribute Detail Citation: FEMA's FIRM Database Technical Reference contains a detailed description of each attribute code and a reference to other relevant information.
Entity and Attribute Detail Citation: The following tables may be included in this data set: L_Comm_Info L_Comm_Revis L_Cst_Model L_Cst_Struct L_Cst_Tsct_Elev L_ManningsN L_Meetings L_MT2_LOMR L_Mtg_POC L_Pan_Revis L_Pol_FHBM L_Profil_Bkwtr_El L_Profil_Label L_Profil_Panel L_Source_Cit L_Summary_Discharges L_Summary_Elevations L_Survey_Pt L_XS_Elev L_XS_Struct S_Alluvial_Fan S_Base_Index S_BFE S_CBRS S_Cst_Gage S_Cst_Tsct_Ln S_Datum_Conv_Pt S_FIRM_Pan S_Fld_Haz_Ar S_Fld_Haz_Ln S_Gage S_Gen_Struct S_HWM S_Hydro_Reach S_Label_Ld S_Label_Pt S_Levee S_LiMWA S_LOMR S_Nodes S_PFD_Ln S_PLSS_Ar S_Pol_Ar S_Profil_Basln S_Riv_Mrk S_Stn_Start S_Subbasins S_Submittal_Info S_Topo_Confidence S_Trnsport_Ln S_Tsct_Basln S_Wtr_Ar S_Wtr_Ln S_XS Study_Info
Distribution Information:
Distributor:
Contact Information:
Contact Organization Primary:
Contact Organization: FEMA, Flood Map Service Center
Contact Address:
Address Type: mailing
Address: P.O. Box 3617
City: Oakton
State or Province: Virginia
Postal Code: 22124
Country: USA
Contact Voice Telephone: 1-877-336-2627
Contact Electronic Mail Address: FEMAMapSpecialist@riskmapcds.com
Contact Instructions: Data requests must include the name and FIPS code of each State or Territory covered by the request, along with an MSC account number if applicable.
Distribution Liability: No warranty expressed or implied is made by FEMA regarding the utility of the data on any other system nor shall the act of distribution constitute any such warranty.
Standard Order Process:
Digital Form:
Digital Transfer Information:
Format Name: NFHL Status Page
Format Information Content: Provides up-to-date information regarding NFHL changes including Alerts, Announcements, and the NFHL Inventory table
Digital Transfer Option:
Online Option:
Computer Contact Information:
Network Address:
Network Resource Name: http://www.floodmaps.fema.gov/NFHL/status.shtml
Digital Form:
Digital Transfer Information:
Format Name: NFHL Interactive Map (FEMA GeoPlatform)
Format Information Content: This is an online mapping resource for the National Flood Hazard Layer.
Digital Transfer Option:
Online Option:
Computer Contact Information:
Network Address:
Network Resource Name: http://fema.maps.arcgis.com/home/item.html?id=cbe088e7c8704464aa0fc34eb99e7f30
Digital Form:
Digital Transfer Information:
Format Name: Fact Sheet: National Flood Hazard Layer (NFHL)
Format Information Content: This fact sheet provides more information about the NFHL in a pdf format.
Digital Transfer Option:
Online Option:
Computer Contact Information:
Network Address:
Network Resource Name: http://www.fema.gov/media-library/assets/documents/13424
Digital Form:
Digital Transfer Information:
Format Name: Get Flood Maps and Data from FEMA
Format Information Content: Current effective maps and data at the county and state level are available here. The FEMA Flood Map Service Center (MSC) is the official public source for flood hazard information produced in support of the National Flood Insurance Program (NFIP). Use the MSC to find your official flood map, access a range of other flood hazard products, and take advantage of tools for better understanding flood risk.
Digital Transfer Option:
Online Option:
Computer Contact Information:
Network Address:
Network Resource Name: http://msc.fema.gov
Digital Form:
Digital Transfer Information:
Format Name: Download Seamless Nationwide NFHL GIS data
Format Information Content: The most recent nationwide extract of the National Flood Hazard Layer is located here. The filename contains the date of the extract. Current effective extracts at the county level can be found at msc.fema.gov. NFHL_National_... contains a subset of the NFHL data, in ESRI's File Geodatatbase format, and when uncompressed is about 12 Gb. The dataset will require the decompression uitlity 7zip (http://www.7-zip.org/) to decompress, and all numbered files from *.001 onward will need to be downloaded. The layers included are: Flood Map Panel boundaries (S_FIRM_Pan), Flood Hazard Zone Boundaries (S_Fld_Haz_Ar), Base Flood Elevations (S_BFE), Cross Sections (S_XS), General Structures (e.g. culverts) (S_Gen_Struct), Coastal Barrier Resources System areas (S_CBRS), LOMR Boundaries for LOMRs since map has gone effective (S_LOMR), and Study information and Cross Section lookup tables.
Digital Transfer Option:
Online Option:
Computer Contact Information:
Network Address:
Network Resource Name: https://content.femadata.com/FIMA/Risk_MAP/NFHL/
Digital Form:
Digital Transfer Information:
Format Name: FIRM Database Technical Reference
Format Information Content: This document contains information about the database schema (fields, tables, etc) that make up the FIRM Database and National Flood Hazard Layer GIS data.
Digital Transfer Option:
Online Option:
Computer Contact Information:
Network Address:
Network Resource Name: http://www.fema.gov/media-library-data/1449862521789-e97ed4c7b7405faa7c3691603137ec40/FIRM_Database_Technical_Reference_Nov_2015.pdf
Digital Form:
Digital Transfer Information:
Format Name: Using NFHL GIS Web Services
Format Information Content: This web page has information on accessing web map services of the NFHL, including REST, OGC Web Map Service (WMS), and OGC Web Feature Service (WFS) protocols.
Digital Transfer Option:
Online Option:
Computer Contact Information:
Network Address:
Network Resource Name: https://hazards.fema.gov/femaportal/wps/portal/NFHLWMS
Fees: Contact Distributor
Metadata Reference Information:
Metadata Date: 20160516
Metadata Contact:
Contact Information:
Contact Person Primary:
Contact Person: Flood Map Service Center
Contact Organization: Federal Emergency Management Agency
Contact Address:
Address Type: mailing
Address: 500 C Street, S.W.
City: Washington
State or Province: District of Columbia
Postal Code: 20472
Country: USA
Contact Voice Telephone: 1-877-336-2627
Contact Electronic Mail Address: FEMAMapSpecialist@riskmapcds.com
Metadata Standard Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata Standard Version: FGDC-STD-001-1998
Metadata Extensions:
Online Linkage: https://content.femadata.com/FIMA/Risk_MAP/NFHL/metadata/
Online Linkage: http://www.epsg.org
Profile Name: FEMA NFIP Metadata Content and Format Standard