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This is a Non-Federal dataset covered by different Terms of Use than See Terms

National Flood Hazard - Letter of Map Revision (LOMR)

Metadata Updated: April 13, 2023

The S_LOMR feature class should contain at least one record for each Letter of Map Revision incorporated into the NFHL. Multipart polygons are not allowed. The spatial entities representing LOMRs are polygons. The spatial information contains the bounding polygon for each LOMR area, broken on panel boundaries.Technical Reference - 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 at 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.

Access & Use Information

Public: This dataset is intended for public access and use. Non-Federal: This dataset is covered by different Terms of Use than See Terms License: See this page for license information.

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Metadata Created Date April 13, 2023
Metadata Updated Date April 13, 2023

Metadata Source

Harvested from Louisville Open Data

Additional Metadata

Resource Type Dataset
Metadata Created Date April 13, 2023
Metadata Updated Date April 13, 2023
Publisher Louisville/Jefferson County Information Consortium
Data First Published 2016-09-21T15:16:31.000Z
Data Last Modified 2023-04-13T11:13:47.988Z
Category geospatial
Public Access Level public
Bureau Code 010:86, 010:04
Metadata Context
Schema Version
Catalog Describedby
Culture en-us
Harvest Object Id 6f446d43-4f2e-4eea-8f22-f37bfa8aba4a
Harvest Source Id df573dd9-dda2-439d-be4a-c5a3e9b0cc03
Harvest Source Title Louisville Open Data
Homepage URL
Metadata Type geospatial
Old Spatial -158.2098,18.0366,-65.6898,64.8467
Platform ArcGIS Hub
Program Code 015:001, 015:002
Source Datajson Identifier True
Source Hash e36cdc9a19d4aabb61a4822defd47ae72f6e9a5f
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -158.2098, 18.0366, -158.2098, 64.8467, -65.6898, 64.8467, -65.6898, 18.0366, -158.2098, 18.0366}
Summary Letter of Map Revision (LOMR) areas from the FEMA National Flood Hazard Layer (NFHL)

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