DORRANCE, Ohio — The city will close the pedestrian bridge over the Dorrance bypass from 8 p.m. to 6 a.m. this week while engineers inspect complaints of footsteps continuing across the span after walkers have stopped. The bridge will remain open during daytime hours, and the road beneath it is unaffected.
The enclosed steel bridge connects the North Terrace apartments with a bus stop, grocery store and medical offices on the west side of the bypass. About 430 people cross it on an average weekday. The nearest marked street crossing adds approximately 12 minutes to the walk between the apartments and the bus stop.
The first report came September 30 from nursing assistant Camila Shore, who uses the bridge after an evening shift. Shore said she heard a second pair of steps behind her matching the pace of her work shoes. When she stopped near the center to let the other person pass, the steps continued toward her, moved beside her and proceeded down the west ramp. She saw no one else on the span.
Eleven similar reports were submitted to the city's service line over six days. Some walkers heard the additional steps behind them and others ahead. Several said the sound used their own uneven rhythm, including a scrape, limp or pause to adjust a bag. No caller reported being touched or seeing another person.
A college student ran from the bridge Friday after the sound changed from a walk to a run at the same moment he accelerated. He fell on the west ramp and sprained his wrist. The city treated the injury as a fall on a dry, unobstructed surface and has added temporary signs directing evening users to the street crossing.
Enclosed bridges can return footfall noise from metal panels and concrete joints, transportation acoustician Lena Moss said after reviewing the city's description. Traffic below can also mask the first echo and make a repeated sound seem separate from the walker. Moss said an echo should cease with its source, though the apparent direction may remain difficult to judge.
City engineers walked the span in pairs Monday while other employees watched both entrances. During four tests, the second walker stopped as soon as the first raised a hand. In three tests, all footfall noise ended. During the fourth, employees at both ends heard 11 additional steps continue toward the west ramp after both walkers stood still.
The bridge deck, expansion joints and mesh enclosure showed no loose panels or obvious structural defect. Accelerometers recorded ordinary vibration from passing trucks but no separate load during the 11-step sequence. Engineers said the closure is precautionary and does not indicate that the bridge is unsafe.
The transit authority will move the westbound evening stop to Market Street during the closure and honor transfers from riders delayed by the detour. The city has asked the apartment manager to keep the east approach lighted and will place staff at both gates during the first two nights.
Maintenance workers locked the bridge at 8 p.m. Tuesday and remained on opposite landings with the span empty between them. At 8:17, the overhead lights switched on in order from east to west, although their motion sensor is designed to activate the full row at once. Neither worker heard footsteps.
As the final light came on, the west handrail lowered slightly, returned, then lowered again at intervals along the last 30 feet of the bridge. The movement reached the locked gate and stopped. Inspection photographs show no bent rail or loose mounting plate, and the gate remained secured until morning.