The Forest Preserves of Cook County (FPCC) owns seven low-head dams on the Des Plaines River and North Branch Chicago River. These dams were built between 1918 and 1968 for recreation, transportation, and sanitary waste purposes. Today, with regional waste water treatment plants and roadway/highway bridges, these dams no longer serve their original purposes. In fact, these dams prevent the passage of riverine fishes, trap bedload material of sand and gravel, and are hazardous to canoeing and paddlers. In addition, these dams were identified to be causing a decline in habitat quality by altering normal river hydraulics and hydrology within the river channel and its adjacent floodplain, while deterring the natural recolonization of fish. Based on this, FPCC is partnering with the Chicago District of the U.S. Army Corps of Engineers (ACoE) and the Illinois Department of Natural Resources (IDNR) to remove or modify these seven dams.
To begin, ACoE, as part of their Planning Assistance to States Program, is preparing two separate Integrated Planning Reports and Environmental Assessments—one for the Des Plaines River dams and one for the North Branch Chicago River dams—that present the conclusions and associated affects/effects for the removal of the seven low-head dams. The reports summarizes the 1) study purpose and need, 2) most cost effective and feasible methods for removal of the dams, 3) affected environment, and 4) direct, indirect and cumulative effects. As part of this first phase, IDNR is providing technical assistance for hydrologic and hydraulic modeling and sediment analysis.
Based on the ACoE reports, IDNR will prepare the final engineering plans and specifications and permit applications for the removal of the seven dams. The IDNR may self-perform the removal of some dams and will contract with private construction companies for the removal of the remainder.
Dams that will be removed as part of this project:
- Dam #1 (Des Plaines River)
- Dam #2 (Des Plaines River)
- Dempster Avenue Dam (Des Plaines River)
- Touhy Avenue Dam (Des Plaines River)
- Dam #4 (Des Plaines River)
- Winnetka Road Dam (North Branch Chicago River)
- Chick Evans Golf Course Dam (North Branch Chicago River)
Des Plaines River Dams
Winnetka & Chick Evans Dams
Schedule for dam removal:
- Dam #1: 2014 (COMPLETED)
- Dam #2: 2014 (COMPLETED)
- Dempster Avenue Dam: Fall 2016
- Touhy Avenue Dam: TBD
- Dam #4: TBD
- Winnetka Road Dam (COMPLETED)
- Chick Evans Golf Course Dam: TBD
In the winter of 2010-2011, the Ryerson Woods Dam was the first dam to be removed on the Des Plaines River, accomplished by the Lake County Forest Preserve District (LCFPD). In the winter of 2011-2012, ACoE, in partnership with the IDNR and FPCC removed the Armitage Dam and Fairbanks Dam on the Des Plaines River. Hofmann Dam in Riverside, reaching 9-feet in height, was removed in the summer of 2012.
LCFPD is moving forward with the removal of the Wright Woods Dam and MacArthur Woods Dam, which is scheduled for 2017.
The removal of these five dams would complete the defragmentation of the upper Des Plaines River mainstem, in which it will then free flow from its headwaters in Racine County, Wisconsin to the Brandon Road Lock & Dam in Joliet. The series of locks and dams on the lower Des Plaines and Illinois River are only partial barrier to fishes, and over the long term do not prevent the intermingling of subpopulations above and below; however, these structures do cause impairment to riverine natural dynamics, instream hydraulics, instream habitat and floodplain habitats. The implementation of the removal of the last five dams on the upper Des Plaines River would essentially connect the headwaters to the Mississippi River.
ACoE and IDNR are currently partnering with the Niles Park District to study, design, and remove the Tam O’Shanter Dam, located in Niles.
Questions? Comments? Please contact Eric Otto at 708-771-1382 or eric.otto [at] cookcountyil.gov.