The Fawell Dam is located on the West Branch of the DuPage River in the McDowell Grove Forest Preserve upstream of the City of Naperville. It was constructed between 1969 and 1971 by the Illinois Department of Transportation Division of Water Resources (now known as the Illinois Department of Natural Resources/Office of Water Resources). The purpose of the dam was to store floodwaters on the West Branch and thus reduce flood heights and flood damages in downtown Naperville. Moveable (operable) gates are present on the spillway (outlet) of the dam. The IDNR/OWR owned and maintained the dam until 1998, when ownership and maintenance responsibilities were transferred to DuPage County.
The Dam is approximately 26 feet high and has a crest length of approximately 1480 feet. The outlet works consist of three 10 feet by 10 feet slide gates and similarly sized concrete box culverts passing through the dam. The slide gates are opened/closed as a function of reservoir water levels upstream of the dam during storm events. The County recently updated two cameras located at the dam. This allows remote monitoring of water surface elevations as well as monitoring for security purposes.
Click to view the Fawell Dam Saddle Dike Piezometer Page This link will open a new browser window and take you back to the main DuPage County website.
Normal Dam Operating Procedures
Operation of the Fawell Dam gates is outlined in the table below. The gates are to be opened as a function of reservoir water levels upstream of the dam during storm events.
During the receding stage of very large storm events that require the flood control gates to be raised to a 7.5 ft. opening or higher, the operating plan will be followed in reverse except that the flood control gates will not be lowered below a 6.0 ft. opening. Once the stream and flood pool upstream of the dam have receded, the flood control gates will be returned to the fully open 10.0 ft. position.
For rainfall events that only require a 4.0 ft., 5.0 ft., or 6.0 ft. gate opening, the flood control gates will remain at that setting until the stream and flood pool upstream of the dam have receded.
Fawell Dam Operating Plan
|Water Surface Elevation (NAVD88)
|Gate Opening (Percent)
|670.00 - 680.23
|680.24 - 686.75
|686.76 - 687.75
|687.76 - 688.75
|688.76 - 690.75
|690.76 and Higher
Current Operating Conditions
Water Surface Elevations
The Fawell Dam stream gage reading in table 2 may be inaccurate due to current weather conditions such as; ice build-up, fog, and/or debris. Please view the staff gage in camera image Fawell Dam #1 - Gates to confirm the stream elevation.
|Stream Level @ Dam
*There is a 20 minute delay on the gage reporting data
|Naperville Pedestrian Bridge