PROJECT DESCRIPTION

ISTHA Grading & Drainage improvements – I-90 WB at Rt 47 Southbound exit ramp. The main intent of this project was to fill the existing detention basin on the outside shoulder of the exit ramp for public safety, & construction of an articulated concrete revetement system for storm water conveyance. This involved utilizing embankment material from both a Tollway owned borrow source & the infield of the interchange. Grading improvements were made site wide, expanding the dry capacity of the infield pond, while reducing the storm storage capacity. Additional improvements consisted of storm sewer structure installation, box culvert extension, reconstruction of the existing riprap stilling basins, roadway lighting improvements, & signage upgrades for motorist safety.