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Flood — Hamlin, SD

Aug 6, 2025

Flood Cause
Heavy Rain

Heavy rainfall of 2 to 4 inches across Codington and Hamlin counties, falling on already saturated soils due to above normal precipitation through the spring and summer months, resulted in flooding of the Big Sioux River and its tributaries including Mud and Willow Creeks. Flooding would mainly be limited to low spots and agricultural lands, however.

Source: NOAA National Weather Service Storm Events Database (event 1290194). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Hamlin, SD

This event is one of many recorded floods in Hamlin County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.

View Hamlin County flood data →

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