Long Run near Lemont, IL

Cook County, Illinois · USGS gauge 05537500 · NWS LLCI2 · Illinois river levels

Is Long Run near Lemont, IL flooding right now?

Long Run near Lemont, IL measured 2.65 ft on 2026-09-22 21:00:00 UTC. That observation was 3.4 ft below its 6 ft flood stage. This is the latest available reading, not a guarantee of current conditions.

Gauge height

2.65 ft

as of 47 min ago

Streamflow

72 cfs

data refreshed just now

Minor flooding here begins at 6 ft, with major flooding at 10 ft. The highest crest on record was 11.1 ft on Thu, Jul 18, 1996.

Streamflow outlook

NOAA National Water Model forecast, issued 10 hours ago. The NWM models discharge for every river reach in the country, including the many gauges the National Weather Service does not forecast individually. It is a model, not an official NWS river forecast, and it predicts flow rather than water level.

Flood stages at this gauge

Category	Stage	Current distance
Action	5 ft	2.4 ft below
Minor flood	6 ft	3.4 ft below
Moderate flood	8 ft	5.3 ft below
Major flood	10 ft	7.3 ft below

New to these numbers? What does flood stage mean? · How to read a river gauge · Why is the river rising?

Highest crests on record

Stage	Date
11.1 ft	1996-07-18
9.91 ft	1954-10-10
9.37 ft	1957-07-13
9.01 ft	1981-06-13
8.94 ft	2011-06-09

Nearby gauges

Gauge	Distance	County
Chicago Sanitary and Ship Canal at Lemont, IL	2.5 mi	Cook County
Des Plaines River near Lemont, IL	2.5 mi	Will County
Chicago Sanitary and Ship Canal at Romeoville, IL	3.1 mi	Will County
Des Plaines River at Romeoville, IL	3.5 mi	Will County
Chicago Sanitary and Ship Canal near Lemont, IL	3.8 mi	DuPage County

Provisional data: Real-time readings are provisional and subject to revision by the USGS — sensors can be affected by ice, debris, or equipment malfunction. Do not rely on this site for decisions involving personal safety; follow official guidance from the National Weather Service and local authorities.

Sources: USGS monitoring location · NWS gauge & forecast