Ronald Reagan Tollway – I-88

Map of I88At a Glance:

  • 96 mile segment of road
  • 240,000 vehicles/day
  • 26 listed species
  • 2 federally protected:
    › Northern Long-eared Bat
    › Mead’s Milkweed

The Reagan Memorial Tollway (I-88) connects the Eisenhower Expressway (I-290) to Illinois Tollway’s western terminus at Dixon, Illinois, and carries over 240,000 vehicles per day. Proposed construction work included maintenance and repairs of roadways, bridges, and ramps. Additionally, roadway work included replacing a bridge over an abandoned railroad right-of-way, now part of the Illinois Prairie Path.

Two federally listed species have occurrence records nearby: NLEB and Indiana Bat.

We surveyed the bridge and nearby areas for roosts and found:

      • no trees >3 inch diameter at breast height and exfoliating bark in immediate area
      • 3 trees with 3 inch diameter at breast height and exfoliating bark nearby
      • no NLEB or Indiana bats observed using the bridge to roost


Niemiller, M.L., T.C.Hohoff, and M.J. Dreslik. 2017. Habitat assessment for Northern Long-eared Bats (Myotis septentrionalis) and Indiana Bats (Myotis sodalis) at I-88 in Lee County, Illinois. ME–17–01:1-20.

Sivicek, V.A., S.A. Johnson, J.L. Jarvis, and M.J. Dreslik. 2019. Noxious and selected invasive plant populations along Illinois toll highway rights-of-way. Illinois Natural History Survey Technical Reports 2019 (28):1–87.

Mui, Jennifer M., Michael J. Dreslik, and Charles A. Warwick. 2021. Illinois Natural History Survey Urban Biotic Assessment Program 2015-2020. INHS Technical Report 2021 (02).

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Visit the Illinois Tollway Website for more information on the construction projects.