What are the types of areas within FEMAs flood insurance rate maps (FIRMS)?
Flood zones are the geographic areas that FEMA has defined according to varying levels of flood risk. The following chart gives a brief description of zones that are present in Ada County. Zone Description X Areas outside of the 1-percent annual chance floodplain A Areas susceptible to flooding, but detailed elevations and hydrologic calculations are not available. The Ada County Zoning Ordinance requires the owner to provide base flood elevation data for the site, prepared by a professional engineer licensed in the state of Idaho, with the submittal of a floodplain development application. See 8-3F-3-3 for more information AE, A1-A30 Areas with a 1-percent annual chance of flooding. Base flood elevations derived from detailed analyses are shown at selected intervals within these zones AH Areas with a 1-percent annual chance of shallow flooding, usually in the form of a pond, with an average depth ranging from 1 to 3 feet. Average flood depths are shown within this zone AO River or str