Rivers in South Dakota

Big Sioux River near Jefferson

Union County, South DakotaNWS BSJS2USGS 06485910Sioux Falls office

Below flood stage
9.59ftStage

Observed Tue, Sep 22, 3:30 PM CDT

Flood stage
31.00 ft
Record crest
44.50 ft2024

Open the live map with the river flood outlook

Flood stages and impacts

CategoryStage
Major flood40.00 ft
Moderate flood35.00 ft
Minor flood31.00 ft
Action28.00 ft
  1. 42.00 ftThe lowest portions of Hwy 12 may begin to flood.
  2. 40.50 ftAt least a couple farmsteads begin to flood.
  3. 37.00 ftWater begins to surround some farmsteads near 329th.
  4. 35.00 ftThe lowest portions of 329th are flooded and the floodplain on the South Dakota side is over a mile wide in some areas.
  5. 31.00 ftSignificant flooding of crop and pasture land begins.

Crest history

12 crests on NOAA’s list since 2015.

#DateStage
1June 24, 202444.50 ft
2March 17, 201940.42 ft
3June 26, 201838.40 ft
4September 18, 201936.74 ft
5April 1, 202024.55 ft
6May 4, 201624.04 ft
7April 15, 202322.39 ft
8May 24, 201720.92 ft
9June 10, 201517.78 ft
10June 2, 202217.57 ft
11July 8, 202515.40 ft
12August 31, 202114.48 ft

Most recent crests

  • July 8, 2025: 15.40 ft
  • June 24, 2024: 44.50 ft
  • April 15, 2023: 22.39 ft
  • June 2, 2022: 17.57 ft
  • August 31, 2021: 14.48 ft
  • April 1, 2020: 24.55 ft
  • September 18, 2019: 36.74 ft
  • March 17, 2019: 40.42 ft
  • June 26, 2018: 38.40 ft
  • May 24, 2017: 20.92 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. Streamflow and the daily record from the U.S. Geological Survey.