Rivers in Illinois
Illinois River at LaGrange Lock and Dam
Below flood stage
10.94ftStage
Observed Tue, Sep 22, 3:00 AM CDT
- Flood stage
- 23.00 ft
- Record crest
- 34.66 ft2015
Flood stages and impacts
| Category | Stage |
|---|---|
| Major flood | 29.00 ft |
| Moderate flood | 27.00 ft |
| Minor flood | 23.00 ft |
| Action | 21.00 ft |
- 36.00 ftLockmasters house and the lower Corps building at the lock and dam begin flooding.
- 35.50 ftLaGrange Road (County Highway 12) is flooded south of LaGrange Lock and Dam.
- 29.50 ftLa Grange Lock Road (County Road 1730N) is flooded just north of the Lock and Dam.
- 28.80 ftCounty Road 500N south of La Grange is closed due to flooding.
- 24.00 ftExtensive wetland acreage south of La Grange begins flooding.
- 23.00 ftAdjacent farmland and wetlands begins flooding. Island Road across the river in western Cass County begins flooding.
- 20.50 ftThe lock wall is completely overtopped.
- 16.50 ftThe earthen part of the dam is overtopped.
- 15.50 ftNormal pool level (429.0 NGVD29).
- 14.00 ftDam goes up at this pool level (427.5 NGVD29).
- 5.60 ftAt and below this height, barge traffic will need to consider lowering tonnage to avoid grounding.
Crest history
41 crests on NOAA’s list since 1973.
| # | Date | Stage |
|---|---|---|
| 1 | July 2, 2015 | 34.66 ft |
| 2 | April 27, 2013 | 34.50 ft |
| 3 | June 1, 1995 | 34.02 ft |
| 4 | June 4, 2019 | 33.89 ft |
| 5 | May 20, 2002 | 33.34 ft |
| 6 | April 19, 1979 | 32.80 ft |
| 7 | April 29, 1973 | 32.00 ft |
| 8 | May 22, 2009 | 32.00 ft |
| 9 | July 29, 1993 | 32.00 ft |
| 10 | May 27, 2020 | 31.35 ft |
| 11 | June 6, 2013 | 31.15 ft |
| 12 | June 29, 2010 | 30.42 ft |
| 13 | April 23, 1993 | 30.00 ft |
| 14 | May 8, 2017 | 29.75 ft |
| 15 | March 19, 2009 | 29.72 ft |
| 16 | January 20, 2005 | 29.44 ft |
| 17 | September 24, 2008 | 29.35 ft |
| 18 | June 28, 2011 | 27.86 ft |
| 19 | November 6, 2009 | 27.65 ft |
| 20 | May 4, 2011 | 27.47 ft |
| 21 | January 6, 2009 | 26.58 ft |
| 22 | March 3, 2001 | 26.40 ft |
| 23 | June 2, 2001 | 26.10 ft |
| 24 | March 7, 2018 | 26.04 ft |
| 25 | February 23, 2008 | 25.72 ft |
Most recent crests
- February 5, 2024: 24.06 ft
- July 7, 2021: 24.27 ft
- May 27, 2020: 31.35 ft
- January 24, 2020: 23.62 ft
- June 4, 2019: 33.89 ft
- April 1, 2019: 24.88 ft
- February 28, 2019: 23.16 ft
- February 17, 2019: 23.93 ft
- March 7, 2018: 26.04 ft
- May 8, 2017: 29.75 ft
Nearby
Upstream, downstream and the gauges around this one.
What this means
Forecasts by the North Central River Forecast Center. Forecasts are issued routinely year-round. 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.
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.