Long Run near Lemont, IL
River level and flood forecast · Cook County
Normal1.0 ftas of Mon 2 PM
The river is 5.0 ft below flood stage (6 ft).
Flow: 9 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Sun, Dec 31, 6 PM. Forecasts change as rain falls and as upstream water arrives.
Flood stages
| Major flood stage | 10 ft |
| Moderate flood stage | 8 ft |
| Flood stage | 6 ft |
| Action stage | 5 ft |
| Record crest (July 18, 1996) | 11.1 ft |
What floods at each level
From the National Weather Service, highest first.
- 10 ftA few residences are threatened near Lemont Road and Janas Drive south of Lemont. A few residences threatened along the creek near Parker Road in Homer Glen.
- 9.5 ftState Street/Lemont Road is threatened south of the creek south of Lemont.
- 8 ftIL-171 (Archer Avenue) is threatened between 135th Street and State Street south of Lemont.
- 7 ft135th Street threatened west of IL-171 (Archer Avenue) south of Lemont. Entrances to numerous residences threatened along 135th Street.
- 6 ftEntrance road to numerous businesses is threatened near 135th Street and IL-171 (Archer Avenue) south of Lemont.
- 5 ftPrivate roads, range land, and forest land are inundated south of Lemont.
Highest crests on record
- 11.1 ft — July 18, 1996
- 9.91 ft — October 10, 1954
- 9.37 ft — July 13, 1957
- 9.01 ft — June 13, 1981
- 8.94 ft — June 9, 2011
Recent crests: 8.94 ft (June 9, 2011) · 8.09 ft (June 27, 2003) · 8.3 ft (February 21, 1997) · 11.1 ft (July 18, 1996) · 9.01 ft (June 13, 1981)
Up and down the river, and nearby
- DownstreamDes Plaines River at Joliet, IL
- Des Plaines River near Lemont, IL
- Chicago Sanitary and Ship Canal at Romeoville, IL
- Chicago Sanitary and Ship Canal at Lemont, IL
- Sawmill Creek (IL) near Lemont, IL
- East Branch Du Page River at Bolingbrook, IL
- Flag Creek near Willow Springs, IL
- West Branch Du Page River near Naperville, IL
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (LLCI2); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.