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Flood — Union, SD

Apr 12, 2023

Rapid snowmelt from a few day period of well above normal temperatures focused on the 11-13th of April resulted in minor to locally moderate flooding through much of the Big Sioux River Basin. Some areas north of I-90 lost between 2 to 5 inches of snow water equivalent (SWE) from the first to second week of April, but antecedent drought conditions resulted in only a percentage of this water actually making it into the river system.

Source: NOAA National Weather Service Storm Events Database (event 1091961). 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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