PropertyShark.com's FEMA Flood Maps

FEMA data quality and map accuracy

Because of several factors, the flood maps generated on this site may differ from other flood maps, including those published by FEMA. These factors include, but are not limited to, differing methods for representing the earth's surface two-dimensionally, and periodic changes to the flood data published by FEMA. Our maps use the most current flood data, which in many cases is more recent, and potentially more accurate, than that used for the official maps.

Map number and publication date

The map numbers listed in our Property Reports are based on a FIRM panel system developed by FEMA, which is an alpha-numeric sequence based on the Federal Information Processing Standard (FIPS), National Institute of Standards & Technology (NIST) and FEMA's own numeric designation for individual communities. The resulting map number for a given property may correspond to an existing official FEMA flood map, or may instead represent a hypothetical map that has yet to be published by FEMA.

PropertyShark's FEMA flood maps are generated from digital source data published by FEMA. The publication date listed in our Property Reports is the date the data was published, and does not necessarily correspond to the publication date of any official FEMA flood map.

Assignment of properties to FEMA Flood Zones

Based on the maps we create from data provided by FEMA, PropertyShark has assigned properties to flood zones based on certain classification criteria, described below. Given the imperfections inherent in both the source data and in mapping technology, we offer no guarantees or warranties regarding the accuracy of this information.

Zone designations and classification criteria

Major zones and sub codes:

Zone A: V, VE, A, AE, AO, AOVEL, AH, A99, 100IC, FPQ, FWIC
Zone B: X500, 500IC
Zone C: X
Zone D: D (unknown, not mapped)

1. Zone A takes precedence over Zone B; Zone B takes precedence over Zone C (X). Within each major zone, the subcategories are listed in rank order (i.e. V takes precedence over VE; VE takes precedence over A, etc.).
2. If a property is 100% covered by a particular flood zone, it was assigned that classification. This holds true even for properties near any transitional boundary between zones.
3. If a property made intersections with multiple flood zone regions, on ANY part of the property (no matter how big it might be) the property was assigned the higher rated Zone classification.

Additional information on flood zones:

http://www.fema.gov/plan/prevent/fhm/fq_gen13.shtm
https://hazards.fema.gov/femaportal/wps/portal/!ut/p/.scr/Glossary#Z
http://www.geoplan.ufl.edu/fgdl/metadata/fgdl_html/fema96.htm

Additional general information on FEMA flood maps:

http://www.gismaps.fema.gov/
https://hazards.fema.gov/femaportal/wps/portal/!ut/p/.cmd/cs/.ce/7_0_A/.s/7_0_DC5/_s.7_0_A/7_0_DC5