FEMA Flood
Dataset
Description
As part of the National Flood Insurance Program, the Federal Emergency Management Agency (FEMA) publish information about flood risk by dissecting the US into 72,000 areas. These are known as FIRM Panels and FIRMettes - Flood Insurance Rate Maps (FIRM). Each FIRM Panel identifies areas (flood zones) in which there is a specific risk of flooding.
Geo ID | 1 : 2d81e65ac27b6aa833d5f5d1d8f14154 |
FIRM Panel | 42081C |
Zone Type | X |
Zone Subtype | 0.2 PCT ANNUAL CHANCE FLOOD HAZARD |
Description | Areas identified in a community's FIS as areas of moderate or minimal hazard from the principal source of flood in the area. However, buildings in these zones could be flooded by severe, concentrated rainfall coupled with inadequate local drainage systems. Local stormwater drainage systems are not normally considered in a community's FIS. The failure of a local drainage system creates areas of high flood risk within these rate zones. Flood insurance is available in participating communities but is not required by regulation in these zones. |
Sourcing
All data about FIRM Panels is sourced from FEMA - see website for further details.
Tables/Views
The following tables can be used to access Flood Risk information. When delivering solutions to customers, some or all of the information found in these tables may be consolidated into one or more views.
DimFEMAFirmPanel
For each FIRM Panel, provides metadata about the panel and when it was last updated by FEMA. Can be used to locate an online version of the FEMA Firm Panel (i.e. map).
Columns: 20
Rows: 170k
GeographyTypeKey: 39
Family: Hazard
DimFEMAFloodHazard
Each FIRM Panel provides a list of the flood zones and the zone types on the map. Each flood zone is a contiguous area. There is one record for each flood panel/flood zone combination.
Columns: 25
Rows: 3.3 million
GeographTypeKey: 40
Family: Hazard
Understanding the Data
Matching to Properties
To match FEMA FIRM Panels and FEMA Flood Zones to individual properties requires the use of FEMA Flood Boundaries. ATTOM matches all properties against the digitized boundaries of all FEMA FIRM Panels and FEMA Flood Zones to establish which, if any, are applicable to a property.
Flood Zone Types
The following are the flood zone types (zonetype) used by FEMA and their descriptions (zonedesc).
Code |
Description |
# Flood Zones |
A | Areas subject to inundation by the 1-percent-annual-chance flood event generally determined using approximate methodologies. Because detailed hydraulic analyses have not been performed, no Base Flood Elevations (BFEs) or flood depths are shown. Mandatory flood insurance purchase requirements and floodplain management standards apply | 342,380 |
A99 | Areas subject to inundation by the 1-percent-annual-chance flood event, but which will ultimately be protected upon completion of an under-construction Federal flood protection system. These are areas of special flood hazard where enough progress has been made on the construction of a protection system, such as dikes, dams, and levees, to consider it complete for insurance rating purposes. Zone A99 may only be used when the flood protection system has reached specified statutory progress toward completion. No Base Flood Elevations (BFEs) or depths are shown. Mandatory flood insurance purchase requirements and floodplain management standards apply | 27 |
AE | Areas subject to inundation by the 1-percent-annual-chance flood event determined by detailed methods. Base Flood Elevations (BFEs) are shown. Mandatory flood insurance purchase requirements and floodplain management standards apply | 733,343 |
AH | Areas subject to inundation by 1-percent-annual-chance shallow flooding (usually areas of ponding) where average depths are between one and three feet. Base Flood Elevations (BFEs) derived from detailed hydraulic analyses are shown in this zone. Mandatory flood insurance purchase requirements and floodplain management standards apply. | 10,838 |
AO | Areas subject to inundation by 1-percent-annual-chance shallow flooding (usually sheet flow on sloping terrain) where average depths are between one and three feet. Average flood depths derived from detailed hydraulic analyses are shown in this zone. Mandatory flood insurance purchase requirements and floodplain management standards apply. | 7,950 |
D | Unstudied areas where flood hazards are undetermined, but flooding is possible. No mandatory flood insurance purchase requirements apply, but coverage is available in participating communities. Flood insurance rates are commensurate with the uncertainty of the flood risk. | 3,438 |
OPEN WATER | A body of open water, such as a pond, lake, ocean, etc, located within a community's jurisdictional limits, that has no defined flood hazard | 533 |
V | Areas along coasts subject to inundation by the 1-percent-annual-chance flood event with additional hazards associated with storm-induced waves. Because detailed hydraulic analyses have not been performed, no Base Flood Elevations (BFEs) or flood depths are shown. Mandatory flood insurance purchase requirements and floodplain management standards apply. | 141 |
VE | Areas subject to inundation by the 1-percent-annual-chance flood event with additional hazards due to storm-induced velocity wave action. Base Flood Elevations (BFEs) derived from detailed hydraulic analyses are shown. Mandatory flood insurance purchase requirements and floodplain management standards apply. | 23,899 |
X | Areas identified in a community's FIS as areas of moderate or minimal hazard from the principal source of flood in the area. However, buildings in these zones could be flooded by severe, concentrated rainfall coupled with inadequate local drainage systes. Local stormwater drainage systems are not normally considered in a community's FIS. The failure of a local drainage sytstem creates areas of high flood risk within these rate zones. Flood insurance is available in participating comunites but is not required by regulation in these zones. | 2,243,367 |
Product Articles (P-Articles)
All solution packs containing the FEMA Flood data element will include the following p-articles to help you understand and use the data: -
- FEMA Flood 101