BRIDGE INSPECTION By JOHN W. McCREE BUREAU OF LOCAL ROADS & STREETS Illinois Department of Transportation

Bridges — nothing is so important or taken more for granted than a bridge. Ask anyone what irritates him or her the most about traveling the roads of Illinois, and they will tell you — being delayed by a moveable bridge in the "up" position, being stalled along the highway waiting for traffic to traverse a one-way section of road that is restricted due to bridge repairs, or being rerouted miles out of their way to bypass a bridge closure.

Bridges are no different than any other part of a highway. They require regular inspection, repair and, eventually, rehabilitation or replacement. In order to properly inspect a bridge and determine repairs or replacement, special training is necessary. Over the last three years, the Illinois Department of Transportation has sponsored three two-week courses to train bridge inspectors. We now have 94 department and 46 local agency employees trained to inspect bridges in Illinois, The importance of training local agency people to do the inspections is becoming more apparent. Plans are being made to schedule another class in January, 1990 to provide training for additional inspectors.

Bridge inspections have been required by the National Bridge Inspection Standards (NBIS) on a biennial basis for years. Local agencies have done the work with their own staff, through assistance from the department, and by hiring consultants.

Guidelines for these inspections are spelled out in the NBIS. We must report to the Federal Highway Administration every year on the status of the biennial bridge inspections. Any structures that have not been inspected within the two years are noted and a schedule of completion of these inspections must be submitted to the department. If inspections are not done, then the FHWA has the option of withholding federal funds until the work is completed and the records updated.

Bridge inspection is a very sensitive issue, especially with recent national attention to bridge failures. Local agencies in Illinois have lost two bridges within the last two months. Fortunately there were no personal injuries, but now many people are inconvenienced because of the extra time it takes to bypass the closed bridges.

Once inspections are completed, the job of bridge posting and/or repairs takes over. Some bridges, regardless of maintenance, still require posting. Posting is probably the hardest item to control. Once you know that a bridge won't carry legal loads, you must warn the traveling public. Studies must be done to determine the weight a bridge can carry and if that weight is less than legal loads, then the signs must go up. The hard part is keeping the signs in place once you install them. Statewide, the local bridges are properly signed at about 95 percent of the bridge sites that require posting. The other 5 percent have been signed initially, but it's a constant battle to keep the signs in place. Continuous surveillance is needed to make sure that the public is warned of the hazard.

Bridge inspection is very important to the local system of highways in Illinois. It needs to be a part of the routine work that local agencies perform. Many counties and municipalities have already reorganized and assigned personnel the continuous duty of bridge inspection. Inspection is no longer an item that can be left at the bottom of your list of priorities when it comes to work on the local system. •

June 1989 / Illinois Municipal Review / Page 5