Fox River at Algonquin tailwater, IL
River level and flood forecast · McHenry County
Normal6.1 ftas of Mon 3:30 PM
The river is 3.4 ft below flood stage (9.5 ft).
Flow: 1,060 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Thu, Oct 1, 9:10 AM. Forecasts change as rain falls and as upstream water arrives.
Flood stages
| Major flood stage | 12 ft |
| Moderate flood stage | 10.5 ft |
| Flood stage | 9.5 ft |
| Action stage | 9 ft |
| Record crest (July 5, 1938) | 14 ft |
What floods at each level
From the National Weather Service, highest first.
- 18 ftInundation of the floodplain reaches more than 1 block from the river in Algonquin.
- 17.5 ftMain Street is threatened in Algonquin.
- 16.5 ftIL-176 threatened near Holiday Hills.
- 16 ftNumerous structures are threatened along Main Street in Algonquin. North Water Reclamation Facility property in Elgin is threatened.
- 15.5 ftAlgonquin Road (IL-62) is threatened west of the river in Algonquin.
- 15 ftInundation reaches up to 2 blocks from the river in Willow Lake Estates in Elgin. Railroad tracks are threatened in downtown Elgin. Multiple structures threatened in downtown Carpentersville. Duncan Avenue threatened north of Elgin.
- 14.5 ftWidespread inundation of roadways and structures reaches 2 blocks from the river near Freeman Park north of downtown East Dundee. A few structures threatened along 1st Street in West Dundee.
- 14 ftResidences threatened along Riverview Drive and Holiday Drive in Holiday Hills. Residences threatened along Riverside Drive West south of McHenry. Structures threatened along North Harrison Street in Algonquin. A few structures threatened along Washington Street in Carpentersville. Algonquin Wastewater Treatment Facility property threatened. Main Street threatened in Carpentersville.
- 13.5 ftBackwater causes Crystal Creek to threaten structures near the village hall in Algonquin. Multiple structures threatened along Wenholz Avenue, Michigan Avenue, North Street, Barrington Avenue, and 2nd Street in East Dundee.
- 13 ftA few structures threatened along Water Street in East Dundee. A few structures threatened along 2nd Street in West Dundee. Structures along Riverside Drive and Grove Ave are threatened in Elgin. Backwater causes Crystal Creek to threaten low-lying sections of Towne Park in Algonquin.
- 12.5 ftResidences threatened along Edwards Avenue in East Dundee. Prairie Trail is threatened at the river in Algonquin. Parking lots threatened in downtown Carpentersville. Low-lying parking lots threatened at Judson College in Elgin.
- 12 ftStructures threatened along River Street, Johnson Street, and Maiden Lane in East Dundee. North Harrison Street threatened near Riverside Park in Algonquin. Washington Street threatened in Carpentersville. Water Street, Edwards Avenue, and Elgin Avenue threatened in East Dundee. Bayview Road threatened in Elgin. Low-lying areas of Festival Park are threatened in Elgin.
- 11.5 ftResidences threatened along Oceola Drive in Algonquin. A few residences threatened along McBride Street in Elgin. Jayne Street and Beach Drive threatened in Algonquin. River Street threatened in East Dundee. Jerusha Avenue threatened in Elgin. Fox River Trail threatened between East Dundee and Elgin.
- 11 ftStructures threatened near Elgin Avenue and Corey Street south of East Dundee. Lincoln Avenue threatened in West Dundee. Filip Street and Fox River Drive threatened in Algonquin. Fox River Trail threatened south of downtown Elgin.
- 10.5 ftStructures threatened along Fox River Drive in East Dundee. Parking lots threatened in downtown West Dundee. Low-lying sections of Cornish Park are inundated in Algonquin. Low-lying sections of Trout Park inundated north of Elgin.
- 10 ftWinaki Trail and Onaway Trail are threatened south of Algonquin. Athletic fields inundated at Judson College in Elgin.
- 9.5 ftFox River Drive threatened in East Dundee. Boathouses threatened along the river in Cary.
- 9 ftWater overflows low-lying river banks along Grove Street in Valley View, along River Shore Drive in Cary, and along Riverview Drive and Holiday Drive in Holiday Hills.
- 8 ftLow-lying trails threatened at Walton Island Park in Elgin.
Highest crests on record
- 14 ft — July 5, 1938
- 13.7 ft — April 6, 1960
- 13.18 ft — July 23, 2017
- 12.7 ft — April 23, 2013
- 12.5 ft — March 24, 1948
Recent crests: 9.43 ft (July 18, 2024) · 10.42 ft (April 9, 2024) · 9.58 ft (April 4, 2023) · 9.11 ft (March 3, 2023) · 11.83 ft (May 23, 2020)
Up and down the river, and nearby
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (AFBI2); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.