Rivers in South Dakota

Elm River near Westport

Brown County, South DakotaNWS WESS2USGS 06471500Aberdeen office

Below flood stage
4.15ftStage

Observed Mon, Sep 28, 9:00 AM CDT

Flood stage
14.00 ft
Record crest
22.63 ft2009

Open the live map with the river flood outlook

Flood stages and impacts

CategoryStage
Major flood19.00 ft
Moderate flood16.00 ft
Minor flood14.00 ft
Action12.00 ft
  1. 22.50 ftThe bridge 2 miles south and 1 mile east of Westport will be overtopped
  2. 22.00 ftLarge portions of Westport will have water 2 to 3 feet deep
  3. 21.00 ftThe bridge on Brown County Road 10a is overtopped
  4. 20.50 ftThe water will reach the bottom of the bridge 2 miles south and 1 mile east of Westport. The bridge east of Westport will be overtopped
  5. 19.00 ftThe community of Westport begins to flood
  6. 18.50 ftThe water will reach the bottom of the bridge east of Westport
  7. 17.50 ftWater reaches the bottom of the bridge north of Westport
  8. 16.00 ftSeveral gravel roads along the river begin to flood
  9. 14.50 ftThe bridge northwest of Kruse Dam will be overtopped
  10. 14.00 ftThe county road east of Westport becomes impassable
  11. 12.50 ftThe water will reach the bottom of the bridge north of Kruse Dam

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

78 crests on NOAA’s list since 1947.

#DateStage
1March 25, 200922.63 ft
2April 10, 196922.11 ft
3March 30, 199721.56 ft
4April 4, 201920.80 ft
5July 27, 202020.45 ft
6April 8, 195220.10 ft
7March 21, 201019.78 ft
8June 11, 200517.78 ft
9March 16, 199517.71 ft
10June 24, 201117.47 ft
11March 17, 196617.40 ft
12March 27, 197817.20 ft
13April 19, 202316.75 ft
14April 3, 198216.24 ft
15March 19, 197215.86 ft
16May 14, 199915.82 ft
17March 17, 199615.40 ft
18March 28, 198915.02 ft
19June 23, 197514.79 ft
20May 4, 202214.39 ft
21April 21, 197913.95 ft
22March 24, 198713.87 ft
23March 22, 199413.62 ft
24April 22, 201813.20 ft
25April 11, 200113.17 ft

Most recent crests

  • August 13, 2025: 9.21 ft
  • April 19, 2023: 16.75 ft
  • May 4, 2022: 14.39 ft
  • October 10, 2021: 5.49 ft
  • July 27, 2020: 20.45 ft
  • April 4, 2019: 20.80 ft
  • April 22, 2018: 13.20 ft
  • February 23, 2017: 12.48 ft
  • August 14, 2016: 9.34 ft
  • May 21, 2015: 10.55 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.