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Flood — Union, SD

Mar 10, 2020

With one to four inches of liquid residing in the snowpack near and north of Interstate 90 at the start of the month, a more or less ideal melting of the winter snowpack in early March produced minor flooding along much of the upper and middle portions of the Big Sioux River Basin.

Source: NOAA National Weather Service Storm Events Database (event 875512). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Union, SD

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

View Union County flood data →

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