Stormwater Management

The Illinois Tollway strives to implement best management practices associated with roadway projects as well as roadway infrastructure to control, reduce and filter stormwater discharge through coordinated efforts in the planning, design and construction phases of a project.

These efforts are developed, implemented and enforced in order to reduce the discharge of pollutants from the Tollway system to protect water quality and to satisfy the appropriate water quality regulations. The Tollway is often required to secure a stormwater permit through project consultation and coordination with the Illinois Environmental Protection Agency.

The Illinois Tollway partnered with the Forest Preserve District of Cook County (FPDCC) to implement a stormwater demonstration project along the North Tri-State corridor in northern Cook County.

The demonstration project includes the use of approximately 17 acres of Forest Preserve Property dedicated for bioswales from Touhy Avenue near O’Hare Airport to Lake Cook Road. The Tollway developed the bioswales project to facilitate the widening and reconstruction of the North Tri-State while at the same time manage the stormwater runoff from the roadway.

We worked with the FPDCC to develop a stormwater management system to reduce stormwater pollutant loadings and volumes. This system was developed with input from the stakeholder groups consisting of the FPDCC staff, federal and state resource agencies, environmental groups, and Tollway staff and consultants. The final stormwater concept includes bioswales along more than 30,000 linear feet of roadway adjacent to the FPDCC.

Planting plans were developed that considered the desire to establish a native plant community, yet one that could tolerate pollutants found in roadway runoff. Once the plans were developed, a maintenance and monitoring plan was compiled to be implemented by the Tollway upon completion of the bioswale installation. Performance standards for these plantings were included in the maintenance and monitoring plans. This stormwater plan, which required approximately 16 acres of FPDCC land received approval by the Cook County Board in July 2007. Bioswales will be constructed in 2010.