Regarded as the nation’s first rails-to-trails conversion in the 1960s, the Illinois Prairie Path spans more than 60 miles through Cook, DuPage and Kane counties. It follows an abandoned railroad right-of-way, running from Maywood to Wheaton and then forking north to Elgin, west to Geneva and Batavia and south to Aurora.
The Aurora branch of the trail crosses under the Reagan Memorial Tollway (I-88) in Naperville between Illinois Route 59 and Eola Road.
As part of the Tollway’s scheduled 2020 maintenance and repairs to the roadway, bridges and ramps on I-88 between the Aurora Toll Plaza and Illinois Route 59, the Illinois Tollway identified the I-88 bridge that crossed over the original railroad—now the Illinois Prairie Path—for improvement.
Working with the Illinois Prairie Path corporation and DuPage County, the Tollway engineers devised a plan to replace the old bridge with a new, modern pedestrian culvert, eliminating disruptions for motorists and reducing the impact of work for hikers and bikers.
And, to save time without adding costs, the path was to be constructed in stages under the existing bridge using castin-place concrete forms instead of precast concrete panels. The same form could be used multiple times, streamlining the process.
Coordination also resulted in a better, more functional underpass. The designed arch shape favored by locals is not only more cost-effective and easier to maintain, it is more aesthetically pleasing and allows in more natural lighting during the day as well as LED lighting to make the underpass brighter.
The Tollway worked with the Illinois Prairie Path corporation to determine the best times to temporarily close the Illinois Prairie Path until the new underpass was completed and provide a safe detour for path users to keep moving.
The new underpass has a vertical clearance of 15 feet and stretches 30 feet wide and also was built 295 feet long— longer than necessary for the existing roadway—to accommodate any future improvements needed on I-88.