Floodplain Information

Flood Insurance Rate Maps (FIRM) 
Polk County adopted new Flood Insurance Rate Maps (FIRM) created by the Federal Emergency Management Agency (FEMA) in September 2011. The maps have not changed significantly but technology/mapping methods showing details have improved.

FEMA Flood Map Service Center 
If you live adjacent to a water body, these new maps may have prompted your bank or mortgage company to send you a letter requiring you to buy flood insurance. If you have not previously been required to carry flood insurance, maps showing the floodplain can be found at FEMA Flood Map Service Center.

Interactive GIS Map (WGXtreme)
The flood hazard boundaries can also be viewed on Polk County’s Interactive GIS Map website, with the flood boundaries overlaid on recent aerial photography.  Click on the Department Maps tab on the GIS website and choose the Zoning Map View. Click on the Floodplains layer on the left side of the screen to view the floodplain boundaries.

FEMA LOMA Process
If your dwelling shows up in the floodplain, but you feel this is an error, FEMA has setup a process to have the structure removed from the floodplain and eliminate the need for flood insurance. In most cases this will be a Letter of Map Amendment (LOMA). It may require you to contact a private land surveyor. An overview of map change processes and the forms required for map changes, to avoid flood insurance, are found at FEMA's LOMA process website.

Polk County Regional Flood Elevations
Determined by Wisconsin Department of Natural Resources

Water Body Elevation Datum
Apple River Amery Dam to Highway 46 – 1066.0 NGVD-29
Balsam Lake 1135.34 NGVD-29
Big Butternut Lake 1215.4 NGVD-29
Cedar Lake 921.0 NAVD-88
Clam Falls Flowage 1029.4 NGVD-29
Largon Lake 1246.7 MSL
Little Butternut Lake 1210.3 NGVD-29
Long Lake 1152.08 / 95.68 NGVD-29 / DNR BM
Lotus Lake 95.4 DNR BM
Sand Lake 1124.0 MSL
White Ash Lake 1123.08 USGS
Wapogasset Lake 1028.2 / 99.4 NGVD-29 / DNR BM
Wapogasset Branch Cross sections from 138th St to 140th St NGVD-29

Floodplain Management
Additional information can also be found at the DNR’s Floodplain management website.

Polk County Division of Zoning
For further questions, please contact the Polk County Division of Zoning.

Related Links and Resources