National Flood Hazard - Letter of Map Revision (LOMR)

Metadata Updated: July 30, 2025

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 - http://www.fema.gov/media-library-data/1449862521789-e97ed4c7b7405faa7c3691603137ec40/FIRM_Database_Technical_Reference_Nov_2015.pdfFlood 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 https://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.

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Dates

Metadata Created Date	April 13, 2023
Metadata Updated Date	July 30, 2025

Metadata Source

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Harvested from Louisville Open Data

Additional Metadata

Resource Type	Dataset
Metadata Created Date	April 13, 2023
Metadata Updated Date	July 30, 2025
Publisher	Louisville/Jefferson County Information Consortium
Maintainer	jane.poole_LOJIC
Identifier	https://www.arcgis.com/home/item.html?id=5ea09a93ebeb4823ab080b9d3059b652&sublayer=1
Data First Published	2016-09-21T15:16:31.000Z
Data Last Modified	2018-01-09T18:42:01.000Z
Category	geospatial
Public Access Level	public
Bureau Code	010:86, 010:04
Metadata Context	https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version	https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby	https://project-open-data.cio.gov/v1.1/schema/catalog.json
Culture	en-us
Harvest Object Id	412ea4ea-9590-4ee7-a688-2ae6fb1375d4
Harvest Source Id	df573dd9-dda2-439d-be4a-c5a3e9b0cc03
Harvest Source Title	Louisville Open Data
Homepage URL	https://louisville-metro-opendata-lojic.hub.arcgis.com/datasets/LOJIC::national-flood-hazard-letter-of-map-revision-lomr
License	https://louisville-metro-opendata-lojic.hub.arcgis.com/pages/terms-of-use-and-license
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	e9bfd07c62d3b30a43d438d66a22cec0c734dea3cb23f042b1b8a5aeaf808e93
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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