Floodplain FIRM Panels

Identification Information:
Citation:
Citation Information:
Publication Date: 20170416
Title: Floodplain FIRM Panels
Edition: Version 1.1.1.0
Geospatial Data Presentation Form: FEMA-NFHL
Description:
Abstract: Location and attributes for FIRM hardcopy map panels. The spatial entities representing FIRM panels are polygons. The polygon for the FIRM panel corresponds to the panel neatlines. 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.
Purpose: The FIRM is the basis for floodplain management, mitigation, and insurance activities for the National Flood Insurance Program (NFIP).
Time Period of Content:
Time Period Information:
Single Date/Time:
Calendar Date: 20170416
Currentness Reference: Publication Date
Status:
Progress: Complete
Maintenance and Update Frequency: Irregular
Spatial Domain:
Bounding Coordinates:
West Bounding Coordinate: -77.125439
East Bounding Coordinate: -76.874561
North Bounding Coordinate: 39.000067
South Bounding Coordinate: 38.749933
Keywords:
Theme:
Theme Keyword Thesaurus: FEMA NFIP Topic Category
Theme Keyword: NFIP
Theme Keyword: Special Flood Hazard Area
Theme Keyword: FIRM Database
Theme Keyword: Riverine Flooding
Theme Keyword: FIRM
Theme Keyword: FEMA Flood Hazard Zone
Theme Keyword: Floodway
Theme Keyword: SFHA
Theme Keyword: Base Flood Elevation
Theme Keyword: Coastal Flooding
Theme Keyword: Flood Insurance Rate Map
Theme Keyword: Coastal Barrier Resources System
Theme Keyword: CBRS
Theme:
Theme Keyword Thesaurus: ISO 19115 Topic Category
Theme Keyword: structure
Theme Keyword: inlandWaters
Theme Keyword: environment
Theme Keyword: hydrology
Theme Keyword: transportation
Theme Keyword: elevation
Theme:
Theme Keyword Thesaurus: NGDA Portfolio Themes
Theme Keyword: Elevation Theme
Theme Keyword: National Geospatial Data Asset
Theme Keyword: NGDA
Place:
Place Keyword Thesaurus: None
Place Keyword: washington dc
Place Keyword: district of columbia
Place Keyword: dc
Access Constraints: Other Constraints
Use Constraints: This work is licensed under a Creative Commons Attribution 4.0 International License.
Point of Contact:
Contact Information:
Contact Organization Primary:
Contact Organization: Federal Emergency Management Agency
Contact Person: Flood Map Service Center
Contact Address:
Address Type: mailing
Address: 500 C Street SW
City: Washington
State or Province: District of Columbia
Postal Code: 20472
Country: US
Contact Voice Telephone: 1-877-336-2627
Contact Electronic Mail Address: mscservices@riskmapcds.com
Point of Contact:
Contact Information:
Contact Organization Primary:
Contact Organization: Office of the Chief Technology Officer
Contact Position: GIS Data Coordinator
Contact Address:
Address Type: mailing and physical
Address: 200 I Street SE
City: Washington
State or Province: DC
Postal Code: 20003
Country: US
Contact Voice Telephone: (202) 727-2277
Contact Electronic Mail Address: dcgis@dc.gov
Hours: 8:30 am - 5 pm
Data Set Credit: Federal Emergency Management Agency
Native Data Set Environment: Esri ArcGIS 13.0.3.36057
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.
Positional Accuracy:
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 Data Organization Information:
Direct Spatial Reference Method: Vector
Point and Vector Object Information:
SDTS Terms Description:
SDTS Point and Vector Object Type: GT-polygon composed of chains
Point and Vector Object Count: 38
Entity and Attribute Information:
Detailed Description:
Entity Type:
Entity Type Label: DCGIS.FldPlnPly_FIRMPanel
Entity Type Definition: Location and attributes for FIRM hardcopy map panels.
Entity Type Definition Source: FEMA FIRM Database Technical Reference (available at https://www.fema.gov/sites/default/files/2020-02/FIRM_Database_Technical_Reference_Feb_2019.pdf)
Attribute:
Attribute Label: OBJECTID
Attribute Definition: Internal feature number.
Attribute Definition Source: Esri
Attribute:
Attribute Label: DFIRM_ID
Attribute Definition: Study Identifier. For a single-jurisdiction Flood Risk Project, the value is composed of the two-digit State FIPS code and the four-digit FEMA CID code (e.g., 480001). For a countywide Flood Risk Project, the value is composed of the two-digit State FIPS code, the three-digit county FIPS code and the letter “C” (e.g., 48107C). Within each FIRM Database, the DFIRM_ID value will be identical.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: VERSION_ID
Attribute Definition: Version Identifier. Identifies the product version and relates the feature to standards according to how it was created
Attribute Definition Source: FEMA
Attribute:
Attribute Label: FIRM_ID
Attribute Definition: Primary key for table lookup. Assigned by table creator.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: ST_FIPS
Attribute Definition: State FIPS. This is the two-digit code that corresponds to the State Federal Information Processing Standard (FIPS) code. This is a standard numbering system used by the Federal government, defined in FIPS Pub 6-4. These two numbers correspond to the first two digits of the panel number. Acceptable values for this field are listed in the D_State_FIPS table.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: PCOMM
Attribute Definition: Community or County Identification Number. This is the third through the sixth digits of the panel number. For communitybased maps this corresponds to the FEMA Community Identification number. For countywide maps this is the county (or county equivalent) FIPS code with a “C.”
Attribute Definition Source: FEMA
Attribute:
Attribute Label: PANEL
Attribute Definition: Panel Number. This is seventh through the 10th digits in the complete panel number. This is assigned by the scale of the map and the position within the community or county. The panel number scheme is described in detail in the FIRM Panel Technical Reference
Attribute Definition Source: FEMA
Attribute:
Attribute Label: SUFFIX
Attribute Definition: Map Suffix. This is the final digit in the complete panel number. This is a letter suffix at the end of the panel number. The map suffix is incremented one letter every time the panel gets republished.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: FIRM_PAN
Attribute Definition: FIRM Panel Number. This is the complete 11-digit FIRM panel number, which is made up of ST_FIPS, PCOMM, PANEL and SUFFIX. This is the FIRM panel number that is shown in the title block of the map.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: PANEL_TYP
Attribute Definition: Panel Type. The type of FIRM panel identifies whether the panel is printed or not and whether it is community based or countywide. Acceptable values for this field are listed in the D_Panel_Typ table.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: PRE_DATE
Attribute Definition: Preliminary Release Date. This is the preliminary release date of the current map revision. This field is not populated until the FIRM preliminary release date is established and the Prelim FIRM is ready for hardcopy production by the Mapping Partner. Then it is required.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: EFF_DATE
Attribute Definition: Effective Date. This is the effective date of the current map revision. This field is not populated until the FIRM effective date is established and the Final FIRM is ready for hardcopy production by FEMA. Then it is required.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: SCALE
Attribute Definition: Map Scale. This is the denominator of the FIRM scale as a ratio. For example, 24000 is the denominator for a 1″ = 2000′ map. Acceptable values for this field are listed in the D_Scale table.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: PNP_REASON
Attribute Definition: Panel Not Printed Reason. This is the explanation for the FIRM panels that are not printed. Only completed if the hardcopy panel is not printed by FEMA. For example, “No Special Flood Hazard Areas.” See the FIS Report Technical Reference for commonly used values.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: NW_LAT
Attribute:
Attribute Label: NW_LONG
Attribute:
Attribute Label: SE_LAT
Attribute:
Attribute Label: SE_LONG
Attribute:
Attribute Label: BASE_TYP
Attribute Definition: Base map type. The type of base map used for the FIRM panel shall be recorded in this field. Acceptable values for this field are listed in the D_Basemap_Typ table.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: SOURCE_CIT
Attribute Definition: Source Citation. Abbreviation used in the metadata file when describing the source information for the feature. The abbreviation must match a value in L_Source_Cit.
Attribute Definition Source: FEMA
Attribute:
Attribute Label: SHAPE
Attribute Definition: Feature geometry.
Attribute Definition Source: Esri
Attribute:
Attribute Label: SE_ANNO_CAD_DATA
Attribute:
Attribute Label: GIS_ID
Attribute Definition: OCTO GIS sequential identifier
Attribute Definition Source: OCTO
Attribute:
Attribute Label: GLOBALID
Attribute Definition: Global ID
Attribute Definition Source: OCTO
Attribute:
Attribute Label: CREATOR
Attribute Definition: A user who created a record.
Attribute Definition Source: OCTO
Attribute:
Attribute Label: CREATED
Attribute Definition: The dates a record were created
Attribute Definition Source: OCTO
Attribute:
Attribute Label: EDITOR
Attribute Definition: A user who last edited a record.
Attribute Definition Source: OCTO
Attribute:
Attribute Label: EDITED
Attribute Definition: The dates a record were last edited.
Attribute Definition Source: OCTO
Attribute:
Attribute Label: GFID
Attribute:
Attribute Label: SHAPE.AREA
Attribute:
Attribute Label: SHAPE.LEN
Distribution Information:
Distributor:
Contact Information:
Contact Organization Primary:
Contact Organization: Office of the Chief Technology Officer
Contact Position: GIS Data Coordinator
Contact Address:
Address Type: mailing and physical
Address: 200 I Street SE, 5th Floor
City: Washington
State or Province: DC
Postal Code: 20003
Country: US
Contact Voice Telephone: (202) 727-2277
Contact Facsimile Telephone: (202) 727-6857
Contact Electronic Mail Address: dcgis@dc.gov
Hours: 8:30 am - 5 pm
Distribution Liability: See access and use constraints information.
Custom Order Process: DC datasets can be downloaded from "http://opendata.dc.gov".
Metadata Reference Information:
Metadata Date: 20230928
Metadata Contact:
Contact Information:
Contact Organization Primary:
Contact Organization: Office of the Chief Technology Officer
Contact Position: GIS Data Coordinator
Contact Address:
Address Type: mailing and physical
Address: 200 I Street SE
City: Washington
State or Province: DC
Postal Code: 20003
Country: US
Contact Voice Telephone: (202) 727-2277
Contact Electronic Mail Address: dcgis@dc.gov
Hours: 8:30 am - 5 pm
Metadata Standard Name: FGDC Content Standard for Digital Geospatial Metadata
Metadata Standard Version: FGDC-STD-001-1998
Metadata Time Convention: local time