Search
Menu

Explore

Hazards

Analysis

Rankings

Reference

Long Run near Lemont

Highest listed crest 11.10 ftFlood stage 6.0 ft11 crests since 1952

The Long Run near Lemont crested at major flood stage 1 time among the 11 crests the National Weather Service lists from 1952 to 2011. The highest, 11.10 ft on July 18, 1996, was major flooding, 5.10 feet above flood stage.

The gauge

Highest listed crest
11.10 ft
July 18, 1996; 5,310 cubic feet per second
Flood stage
6.0 ft
Major flooding from 10.0 ft
Crests at major
1
101st of 177 gauges in Illinois
Most recent flood crest
June 9, 2011
8.94 ft, moderate flooding
Location
Cook County
Near Lemont (1.9 mi), Homer Glen (3.5 mi), Lockport (3.9 mi)

Flood stages

The thresholds the National Weather Service uses for this gauge today, and how many listed crests reached each.

Flood categories, Long Run near Lemont
Action stage5.00—The level at which the NWS or its partners begin to take action
Flood stage (minor)6.00—Minimal or no property damage, but possibly some public threat
Moderate flood stage8.010Jun 9, 2011Some inundation of structures and roads near the stream
Major flood stage10.01Jul 18, 1996Extensive inundation of structures and roads

Every listed crest

11 crests from 1952 to 2011. Filled: at or above flood stage. Hover a crest for its date and stage.

Listed crests at the Long Run near Lemont, 1952 to 2011 681012ft Flood stage 6.0 ftMajor 10.0 ft Jun 13, 1952: 8.18 ft, moderate flooding; 1,000 cubic feet per secondOct 10, 1954: 9.91 ft, moderate flooding; 3,160 cubic feet per secondJul 13, 1957: 9.37 ft, moderate flooding; 2,390 cubic feet per secondMay 12, 1966: 8.32 ft, moderate flooding; 1,360 cubic feet per secondJun 21, 1970: 8.04 ft, moderate flooding; 1,140 cubic feet per secondMay 4, 1979: 8.10 ft, moderate flooding; 530 cubic feet per secondJun 13, 1981: 9.01 ft, moderate flooding; 1,820 cubic feet per secondJul 18, 1996: 11.10 ft, major flooding; 5,310 cubic feet per secondFeb 21, 1997: 8.30 ft, moderate flooding; 1,670 cubic feet per secondJun 27, 2003: 8.09 ft, moderate flooding; 1,500 cubic feet per secondJun 9, 2011: 8.94 ft, moderate flooding; 2,240 cubic feet per second Highest, 11.10 ft, Jul 18, 1996 196019701980199020002010

Crests at or above flood stage, by decade

Crests at or above flood stage per decade, Long Run near Lemont 1950s: 3 3 1960s: 1 1970s: 2 1980s: 1 1990s: 2 2000s: 1 2010s: 1 1950s1960s1970s1980s1990s2000s2010s
  1. These are the crests the local National Weather Service office lists for the gauge: the highest on record and recent crests. Lesser floods between them may be missing, so counts by decade are a floor.
  2. Categories use today's flood stages. Levees, dams and channel changes since a crest can make old and new stages not directly comparable.

Highest crests

Highest listed crests, Long Run near Lemont
1Jul 18, 199611.10+5.10Major5,310
2Oct 10, 19549.91+3.91Moderate3,160
3Jul 13, 19579.37+3.37Moderate2,390
4Jun 13, 19819.01+3.01Moderate1,820
5Jun 9, 20118.94+2.94Moderate2,240
6May 12, 19668.32+2.32Moderate1,360
7Feb 21, 19978.30+2.30Moderate1,670
8Jun 13, 19528.18+2.18Moderate1,000
9May 4, 19798.10+2.10Moderate530
10Jun 27, 20038.09+2.09Moderate1,500
11Jun 21, 19708.04+2.04Moderate1,140

Other gauges in Cook County

Flood gauges in Cook County
Bellwood9.013.57 ft, Jul 24, 20104
Wheeling5.08.46 ft, Jun 26, 20136
Flossmoor9.013.08 ft, Apr 17, 20060
Markham10.012.00 ft, Oct 11, 19542
Chicago (Columbus Dr)3.05.50 ft, Oct 10, 19542
Chicago (Western Ave)4.05.26 ft, May 17, 20200
Chicago Heights10.012.87 ft, Sep 15, 20080
Des Plaines (Algonquin Road)13.021.00 ft, Sep 14, 20082
Lyons18.022.87 ft, Apr 18, 20132
River Forest16.018.98 ft, Apr 19, 20131
Riverside7.511.28 ft, Apr 18, 20137
Des Plaines15.020.92 ft, Apr 19, 20135
Lemont10.013.24 ft, May 18, 20200
Willow Springs10.010.57 ft, Apr 18, 20130
Lake Michigan at Calumet Harbor5.06.07 ft, Aug 11, 20200
Lake Michigan at Chicago (Chicago Lock)4.05.98 ft, Apr 29, 20200
Lansing7.010.18 ft, Oct 11, 19540
South Holland16.020.50 ft, Nov 28, 19905
Mount Prospect5.08.08 ft, Aug 14, 19872
Oak Forest6.09.50 ft, Apr 5, 19472
Midlothian8.59.98 ft, Feb 2, 20160
Chicago (Grand Ave)3.05.70 ft, Oct 10, 19543
Chicago (Pulaski Rd)18.022.50 ft, Aug 14, 19871
Niles10.012.13 ft, Sep 14, 20082
Elgin5.57.69 ft, Sep 13, 20080
Elk Grove Village17.020.80 ft, May 18, 20200
Rolling Meadows8.514.03 ft, Aug 14, 19870
Western Springs7.510.65 ft, Apr 18, 20130
Worth31.036.50 ft, Oct 11, 19542
Glenwood8.511.14 ft, Jul 13, 19570
Thornton9.017.06 ft, Jun 14, 19816
Palos Park9.010.30 ft, Oct 10, 19540
Des Plaines9.015.09 ft, Jun 10, 19677
Northbrook7.010.10 ft, Aug 14, 19877

Cook County: every hazard · River floods across the country · Illinois

NOAA National Water Prediction Service, gauge LLCI2, retrieved October 30, 2026. Stages in feet on the gauge's own datum, not elevation. Crests are as the National Weather Service lists them; preliminary values may be revised.