Tri-County Access Project

Map of TCATri-County Access Project at a Glance:

  • Addresses increase in population and traffic congestion in
  • Lake, Cook, and McHenry Counties
  • 89 listed species
  • 3 federally protected known

› Rusty Patched Bumble Bee
› Northern Long-eared Bat
› Eastern Prairie Fringed Orchid

  •  2 federally protected species possible

› Black Rail
› Hine’s Emerald Dragonfly

First conceived in the 1960s, the Tri-county Access Project (TCA) was proposed to address increased travel demands and ease traffic congestion associated with the continual expansion of urbanization in Lake, Cook, and McHenry counties. In 2011, propoals extending IL-53 and  improving the IL-120 segment were introduced. We conducted preliminary surveys along Rt 53 in 2015 for mussels, aquatic macroinvertebrates, turtles, birds, and plants.


Once the Tollway had identified potential segments to achieve their goals, we analyzed the biotic resources, identifying stream crossings, natural areas, and EORs The federally listed EPFO and RPBB have been found in this region. Although there were no current records, in 2019 the USFWS requested surveys for the HED and the Black Rail.

In 2019, we attempted to confirm the continued existence of these 470 EOR hits of 90 species and survey suitable habitat for other endangered and threatened species in the project area. The construction project was officially suspended in 2019, but our work continued to provide valuable information to the region’s various stakeholders.

  • Twenty-one threatened or endangered species and two sensitive habitat types have been found in the Rt 53 North Extension corridor historically, but our surveys for 2015-17 only detected 6 of the species, 4 plants and 2 fishes.
  • When other potential segments were analyzed, there were 89 known threatened and endangered species