Floodplain BFE (Base Flood Elevation)

open.piercecountywa.gov | Last Updated 14 Aug 2020

This is the 2017 DFIRM Data for Base Flood Elevation lines (BFE). The Base Flood Elevation (BFE) which refers to the elevation associated with the 1% annual chance of flood occurrence in any given year. The Base Flood Elevation (BFE) height is shown as an integer. Reference the profiles found in the Detail Studies for a more precise determination of the BFEs (copies can be obtained through FEMA's website (www.msc.fema.gov) or Pierce County Surface Water Management website (www.piercecountywa.org/flood). The BFE in this data is in NAVD88 (North American Vertical Datum 1988) and measured in feet. The BFEs corresponds to the "AE" zones (AE means an A zone with known elevation) that are shown in the "County Floodplains" data. One product of completing a Detailed Study of a floodplain is the determination of the Base Flood Elevation (BFE). A Detailed Study is also required to map a Floodway. This data identifies to the elevation of the water surface in a 1% Annual Chance Flood and shows where detailed flood studies have been done. Not all areas in a floodplain have BFE/detailed studies. The Base Flood Elevation (BFE) table is required for any digital data where BFE lines will be shown on the corresponding Flood Insurance Rate Map (FIRM). The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk classifications used are the 1-percent-annual-chance flood event, the 0.2-percent-annual- chance flood event, and areas of minimal flood risk. The DFIRM Database is derived from Flood Insurance Studies (FISs), previously published Flood Insurance Rate Maps (FIRMs), flood hazard analyses performed in support of the FISs and FIRMs, and new mapping data, where available. The FISs and FIRMs are published by the Federal Emergency Management Agency (FEMA). The file is georeferenced to earth's surface using the UTM projection and coordinate system. The specifications for the horizontal control of DFIRM data files are consistent with those required for mapping at a scale of 1:12,000. Please read metadata for additional information (https://matterhorn.co.pierce.wa.us/GISmetadata/pdbswm_regulated_floodplain_bfe.html). Any data download constitutes acceptance of the Terms of Use (https://matterhorn.co.pierce.wa.us/Disclaimer/PierceCountyGISDataTermsofUse.pdf).