Winnetka Stormwater Management Wetlands Project at Skokie Lagoons

Plants around a lagoon at Skokie Lagoons.

Beginning in December 2022, the Village of Winnetka will construct and maintain a stormwater management wetland project that includes Hibbard Woods in the Skokie Lagoons, south of Willow Road. The Village approached the Forest Preserves of Cook County with a plan that now includes a variety of additional conveyance, storage and green infrastructure facilities for handling the stormwater. The project at the Skokie Lagoons is subject to an Intergovernmental License Agreement between the Village and the Forest Preserves.

To learn more about the Village’s project, visit their Stormwater Management webpage. For inquiries about the status of the project, please contact James Bernahl, P.E., Village Engineer, at or call (847) 501-6000.

Frequently Asked Questions

What is the scope of the project?

The stormwater management wetland project is slated to cover 15.4 acres of the Skokie Lagoons and include an additional 74 acre-feet of stormwater storage on Forest Preserves land. Construction at the site will include removal of trees, excavation and reshaping of the earth to store and convey water in a meandering channel with new wetland plantings. Tree removal will be completed by the end of 2022 and the remaining work is expected to be completed in 2023.

When construction is complete, nearly half of the stormwater that reaches Skokie Lagoons will be stored at four locations upstream and be held in basins with filtering equipment. This will both reduce the amount of flooding and allow sediment and pollutants to settle before reaching our property. In addition, the license agreement with the Village of Winnetka requires implementation of best management practices and ongoing water quality monitoring.

An exhibit showcasing the overall project area at Hibbard Woods.
An exhibit showcasing the overall project area at Hibbard Woods.

Why is the Forest Preserves taking on extra stormwater?

Typically, the Forest Preserves does not agree to proposals to bring stormwater onto our property because in most cases it arrives with runoff and other pollutants from built surfaces and can alter the hydrology and the ecosystems at the site. However, the Skokie Lagoons were created during the Great Depression as a series of water bodies that would hold stormwater. All stormwater from the western and southwestern portions of the Village has been conveyed through the Skokie Ditch system in Hibbard Woods before the Forest Preserves acquired this property.

Stormwater flooding at the Skokie Ditch system in Hibbard Woods.
The existing Skokie Ditch system in Hibbard Woods.

What will be the impact on Hibbard Woods and the Skokie Lagoons?

Overall, the project will benefit the ecological health of the Forest Preserves land by reducing the number of acres that experience stormwater flooding and how often they are flooded. Currently, Hibbard Woods is entirely flooded with stormwater by 5-year rain events. Once the project is complete, that level will be reduced to 100-year rain events. In addition, there will be significant improvements in the quality of the water flowing onto the property.

The impacted license area in Hibbard Woods includes a small portion of intact wetlands with relatively high floristic quality plants. Outside of the immediate construction zone, the overall health of wetland plant life will improve with the new drainage. Inside that zone, our staff has been actively working alongside dedicated volunteers to identify the impact areas and where best to replant quality plants that are at risk. Forest Preserves staff have worked with the Village to minimize the number of trees that will be removed, prioritizing the highest priority specimens.

Is the Forest Preserves being compensated for this agreement?

Following Forest Preserves requirements, the Village of Winnetka will pay $1.25 million in tree mitigation fees and $500,000 for restoration work at high-priority ecological sites nearby, including Somme Preserves, Chipilly Woods and Harms Woods. Additionally, the Village will pay $250,000 for other public amenities at Skokie Lagoons that may include parking or canoe launch access upgrades, and will pay $2.2 million to a third party to construct a wetland mitigation project on 154 acres in Paul Douglas Preserves.

Who has approved this project?

In 2017, the Forest Preserves of Cook County Board of Commissioners approved a Memorandum of Understanding with basic terms and required conditions for the stormwater management wetland project to proceed. The final scope is the result of five years of planning and negotiation between the Village of Winnetka and the Forest Preserves of Cook County, with input from the U.S. Army Corps of Engineers and concerned volunteers.

A thorough review by the U.S. Army Corps of Engineers resulted in a reduction in the project’s Forest Preserves’ footprint (from 18.6 to 15.4 acres) and avoidance of a high-quality sedge meadow. Other modifications included storage of much of the water off-site before reaching Forest Preserves property and ongoing water quality monitoring. In November, 2022 the U.S. Army Corps of Engineers granted a permit for the project and the Forest Preserves Board voted to approve the Intergovernmental License Agreement. Recognizing the net benefit to the Preserves, long-time ecological stewards support the plan as well.