River Restoration & Wetland Mitigation

Habitat Restoration & Wildlife Conservation Project

West Branch: River Restoration and Wetland Mitigation

The Forest Preserve District and DuPage County Stormwater Management began a 350-acre multiyear restoration project at West Branch Forest Preserve in Bartlett in 2013. This project will restore 1 mile of the West Branch of the DuPage River, 90 acres of wetlands, the 34-acre Klein Fen (a rare type of wetland) and adjoining prairies. In addition to providing healthier habitat for native wildlife, the preserve will receive and store stormwater to benefit neighboring residents.

At one time the land that makes up the preserve contained wet prairies, marshes and fens, and scattered woodlands; these habitats were lost as farmers tilled the prairie and buried clay tiles to drain the soil for crops and pastures. The West Branch of the DuPage River was deepened and straightened to carry water away from agricultural fields and accommodate stormwater runoff, leading to further loss of habitat and floodwater protection. These changes coupled with stormwater drainage from surrounding developments all contributed to an altered landscape. Aggressive and nonnative woody trees and shrubs, such as buckthorn and box elder, took advantage of the disturbance and invasive species populated these artificially-drained areas.

West Branch Forest Preserve and its trails will remain open during most of the work, which should be substantially completed by 2015, but visitors should be careful near construction areas and follow all signs and workers’ instructions. 

During January 2015, contracted crews will be removing trees from the Klein Fen that are visible from Klein Road. This work will provide optimal conditions for this rare type of wetland. The area outlined on the map below depicts the fen restoration project area.

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Wetland Restoration

This project is restoring 90 acres of wetlands to offset the loss of wetland habitat during the expansion of O’Hare Airport. The District is restoring an additional 30. To return the natural distribution of underground and surface water to these 120 acres, crews are removing buried agricultural tiles installed by farmers long ago to drain the soil. They’re also removing trees that spread along the drainage lines. This will not only allow the land to hold more water, especially after heavy rains, but also limit the amount of moisture that’s lost through plant respiration.

 

Along the West Branch of DuPage River

As crews work to reconfigure the river, adding bends, riffles and pools — ideal habitat for a variety of aquatic life — they will need to remove most of the trees along the bank. The majority of these trees, though, will be reused in the river itself as root wads that will stabilize the bank and minimize erosion.

 

Prairie Restoration

By removing rows of trees planted throughout the forest preserve’s more open areas, the District is creating more than 200 acres of uninterrupted grassland. Areas like this are rare in this part of the state but are much-needed nesting habitats for grassland birds. 

 

Drainage Work Along Klein Road

All trees at two preserve areas along Klein Road will be removed to create two large dry wells. The wells will serve to interrupt existing drainage system patterns in a former agricultural field and a storm sewer line in a neighboring residential area. A new perforated drainage system will be buried between the wells to carry water to hydrate the preserve’s upper slope and distribute seepage to re-saturate the lower fen and floodplain. Although trees along this new drainage line and nonnatives in other areas of the preserve will be cleared, native oak and walnut trees will remain intact to complement the ecosystem. For more information, visit dupageco.org/wbdr. 

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Project Funding

The work is funded by a $799,000 Illinois Environmental Protection Agency grant, Forest Preserve District development bonds and money from the City of Chicago's O’Hare Modernization Program, designed to offset the loss of wetlands and habitat during the O'Hare Airport expansion.