Rivers in South Dakota

Big Sioux River near Richland

Union County, South DakotaNWS BSRS2Sioux Falls office

Below flood stage
1107.6ftStage

Observed Sun, Sep 27, 8:00 PM CDT

Flood stage
1117.0 ft
Record crest
1128.7 ft2024

Open the live map with the river flood outlook

Flood stages and impacts

CategoryStage
Major flood1123.0 ft
Moderate flood1119.0 ft
Minor flood1117.0 ft
Action1116.0 ft
  1. 1131.0 ftThe bridge on SD Hwy 50/IA Hwy 3 is overtopped.
  2. 1124.5 ftSouth Dakota Highway 50 begins flooding.
  3. 1123.5 ftIowa Highway 3 begins flooding.
  4. 1123.0 ftBackwater up Brule Creek can begin to cause significant issues in the Richland area where transportation routes in and out of town begin to become a concern.
  5. 1121.0 ftSome farm levees will be overtopped and some farm buildings will be flooded.
  6. 1119.0 ftWidespread flooding of crop and pasture land begins. Water reaches the top of the boat ramp off of Hwy 3 at the gauge.
  7. 1117.0 ftLower pasture lands begin to flood, and the Millsite Access is flooded.

Crest history

9 crests on NOAA’s list since 2014.

#DateStage
1June 23, 20241128.7 ft
2June 18, 20141125.6 ft
3March 16, 20191124.5 ft
4June 24, 20181124.4 ft
5September 17, 20191123.5 ft
6April 1, 20181118.8 ft
7April 1, 20201118.7 ft
8April 15, 20231118.4 ft
9July 6, 20251111.6 ft

Most recent crests

  • July 6, 2025: 1111.6 ft
  • June 23, 2024: 1128.7 ft
  • April 15, 2023: 1118.4 ft
  • April 1, 2020: 1118.7 ft
  • September 17, 2019: 1123.5 ft
  • March 16, 2019: 1124.5 ft
  • June 24, 2018: 1124.4 ft
  • April 1, 2018: 1118.8 ft
  • June 18, 2014: 1125.6 ft

Nearby

Upstream, downstream and the gauges around this one.

What this means

Forecasts by the Missouri Basin River Forecast Center. Forecasts are not available. Only observed stages are available for this point. No forecasts are available for this location Gauge reading may be affected by ice.

Sources

Stage, flood stages, impacts and crest history from NOAA’s National Water Prediction Service.