FEMA Digital Q3 Flood Data

Digital Q3 Flood Data are not tied to a base map, are not used to produce a new version of the FIRM hardcopy, and are not subjected to community review. The digital Q3 Flood Data are designed to provide guidance and a general proximity of the location of Special Flood Hazard Areas. The digital Q3 Flood Data product can be a valuable tool in screening property addresses within a Geographic Information System to determine flood risks.

However, since the geographic processing performed to develop digital Q3 Flood Data may introduce differences with the FIRM hardcopy source, users must apply considerable care and judgment in the application of this product. For instance, digital Q3 Flood Data may be overlaid on highly detailed large-scale community base mapping data, but, if parcel level determinations are made, they must be prefaced with information about the accuracy of the data from which they are derived.

Contents of Q3 Data The vectorized features contained in digital Q3 Flood Data files include: - Annual chance floodplain areas of 1 and 0.2 percent, including Zone V areas, certain floodway areas, and zone designations - Political areas, including community identification numbers - FIRM panel areas, including panel number and suffix - 7.5-minute quadrangle areas - Mapable Letters of Map Change (LOMCs) [Summary provided by FEMA]