March 19, 2025: Lake Pepin is open to the navigation industry and there will be no more ice surveys this year.

Composite 12-Year measurements from 2014-2025 *NEW*

Map: Lake Pepin ice survey locations (PDF)

Lake Pepin ice thickness measurements typically start in mid-February and are conducted on a weekly basis. Measurements are reported from each mile on the Upper Mississippi River between mile 765 and 786. These measurements are taken at the points indicated on the map and the ice thickness is valid for that location only.