Rivers in South Dakota

Big Sioux River at Watertown Sioux Conifer Road

Codington County, South DakotaNWS WBSS2USGS 06479500Aberdeen office

Below flood stage
3.23ftStage

Observed Thu, Sep 24, 4:15 AM CDT

Flood stage
9.00 ft
Record crest
12.49 ft1997

Open the live map with the river flood outlook

Flood stages and impacts

CategoryStage
Major flood12.00 ft
Moderate flood10.00 ft
Minor flood9.00 ft
Action8.00 ft
  1. 15.50 ftThe bridge on 14th Ave NW is overtopped.
  2. 14.00 ftThe bridge on Sioux Conifer Road is overtopped.
  3. 12.00 ftSioux Conifer Road floods south of the gauge, and water reaches the bottom of the bridge at the gauge.
  4. 10.00 ftSignificant amounts of pasture land are flooded.
  5. 8.00 ftMinor lowland flooding begins, mainly upstream of the gauge.

Flood outlook

Chance of flooding, September to November

CategoryChance
Minor floodingUnder 5%
Moderate floodingUnder 5%
Major floodingUnder 5%

The three-month chances are the River Forecast Centers’ long-range flood outlook, issued September 23, 2026.

Crest history

49 crests on NOAA’s list since 1946.

#DateStage
1April 6, 199712.49 ft
2April 7, 200111.58 ft
3April 8, 196911.40 ft
4April 13, 202311.18 ft
5March 28, 201910.98 ft
6April 9, 201110.60 ft
7April 9, 195210.30 ft
8March 30, 196010.29 ft
9April 22, 20189.81 ft
10March 15, 20109.81 ft
11March 23, 20099.77 ft
12May 31, 20229.47 ft
13May 23, 19629.46 ft
14March 22, 20079.24 ft
15August 7, 20259.15 ft
16April 13, 19478.93 ft
17July 28, 19538.92 ft
18October 25, 20198.90 ft
19March 16, 19728.86 ft
20March 26, 19488.30 ft
21March 15, 19468.25 ft
22June 21, 20147.72 ft
23March 30, 20027.66 ft
24March 4, 19707.62 ft
25March 10, 19557.58 ft

Most recent crests

  • August 7, 2025: 9.15 ft
  • April 13, 2023: 11.18 ft
  • May 31, 2022: 9.47 ft
  • April 10, 2021: 6.69 ft
  • October 25, 2019: 8.90 ft
  • March 28, 2019: 10.98 ft
  • April 22, 2018: 9.81 ft
  • June 17, 2017: 6.07 ft
  • April 29, 2016: 4.83 ft
  • March 12, 2015: 7.45 ft

Nearby

Upstream, downstream and the gauges around this one.

What this means

Forecasts by the Missouri Basin River Forecast Center. Forecasts are issued as needed during times of high water, but are not routinely available. River forecasts for this location take into account past precipitation and the precipitation amounts expected approximately 24 hours into the future from the forecast issuance time. River forecasts for this location take into account past precipitation and the precipitation amounts expected approximately 48 hours into the future from the forecast issuance time. 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.