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
- The National Flood Insurance Program - FEMA
- Flood Insurance Basics - PDF FEMA
- Living in the Floodplain - PDF Brochure