Where is it?

With a population of 1.7 million people – expected to grow to 2.1 million people by 2050, the Tri-County Access Study area covers approximately 1,000 square miles in northeastern Illinois and a portion of southern Wisconsin in order to fully understand the transportation problems and potential effects of any alternatives considered. The Study area includes three primary counties – Lake County in its entirety, eastern McHenry County and northern Cook County – with considerations for the travel interrelationship with portions of DuPage and Kenosha counties.

Given existing traffic patterns and demands, it is vital to have a robust Study area that covers the Tri-County region and neighboring communities. An expanded TCA Study area that reaches beyond the primary three counties involved is consistent with the Illinois Tollway’s commitment to taking a comprehensive, regional approach to examining transportation challenges and identifying potential solutions that are both environmentally and fiscally responsible.

Tri-County access study area. Study area approximately 1000 square miles. Three primary counties, Lake, eastern McHenry, and northern Cook. Two adjoining counties, portions of Kenosha and DuPage.