Fema National Flood Hazard Layer

The filename contains the date of the extract. National flood hazard layer (nfhl) dataset is a compilation of effective flood insurance rate map (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 united states and its. Contains a subset of the nfhl data, in esri's file geodatatbase format, and when uncompressed is about 12 gb.

It is updated on a monthly basis. New and revised data is continuously added. The most recent nationwide extract of the national flood hazard layer is located here.

The national flood hazard layer is a computer database that contains fema’s flood hazard map data.

The national flood hazard layer (nfhl) data incorporates all flood insurance rate map (firm) databases published by the federal emergency management agency (fema), and any letters of map revision (lomrs) that have been issued against those databases since their publication date. The primary flood hazard classification is indicated in the flood hazard zones layer. Contains a subset of the nfhl data, in esri's file geodatatbase format, and when uncompressed is about 12 gb. Fema provides access to the national flood hazard layer (nfhl) through web mapping services.