Though the status of major bridges in Illinois compares favorably to those in neighboring states, Illinois nonetheless faces challenges in the form of increasing traffic on many bridges which were not designed for such high demand. Illinois is not at the moment in the kind of danger that Minnesota faced when its I35 W bridge over the Mississippi River collapsed in August 2007, but it is nevertheless true that many bridges in Illinois require maintenance and upgrading, a project which is extremely costly.
Evaluating the Status of Bridges
The Federal Highway Administration evaluates the condition of bridges’ structure in three places; the deck (where cars travel), the superstructure (underneath the deck), and the substructure (foundation). The I-35W bridge in Minnesota was rated “poor” on superstructure, “fair” on deck, and “satisfactory” on substructure. In Illinois, 673 bridges have a rating of “poor” or worse in one of the three key evaluative areas. Four of these bridges are on interstates and 402 are on local roads.
Bridges are eligible for Federal Highway Bridge Replacement and Rehabilitation Program (HBRPP) funding if they receive a rating of “poor” or worse, and are therefore considered “structurally deficient.” They are also eligible if they are considered “functionally obsolete,” or designed for levels of traffic or purposes which are currently outdated or inefficient. 8 percent of bridges in Illinois are functionally obsolete, though 24% of cars which drive across bridges are driving across a functionally obsolete bridge. Thus, heavily traveled bridges seem to be more likely to be functionally obsolete. Illinois’ disparity in this regard is greater than any neighboring states. Still, Illinois ranks well in comparison to neighbors for the number (11%) of structurally deficient bridges and how much traffic they encounter (9%).
Problematic Areas in Illinois
Of all the Illinois regions, Peoria seems to have the greatest problem with deficient bridges. 21 percent of bridge crossings in Peoria are across structurally deficient bridges. The Chicago area, on the other hand, has problem with functionally obsolete bridges, with 27 of bridge crossing there being functionally obsolete due to higher levels of traffic, which affects urban areas in general.
The cost of repairing both structurally deficient and functionally obsolete bridges is quite high; $535 million would be required in the Chicago area just for interstate bridges, and $488 for other principal arterials.
Prospects for Repair in Illinois
It seems that, though it would cost billions of dollars to repair all the structurally deficient or functionally obsolete bridges in Illinois, much benefit would be gained from fixing the most traveled bridges in the state. This way, a larger percentage of traffic is made safer, and money is used efficiently to benefit the largest numbers of people. Using tolling technology, bridges could be leased to private companies and fixed for profit, leaving aside money for other transportation projects, such as the improvement of highway and interstate roadways.
