Genesee County Underwater Bridge Inspections

Ayres completed the underwater inspection of two bridges in Genessee County, Michigan. Ayres provided a three-person underwater inspection team that met National Bridge Inspection Standards (NBIS) and Michigan Department of Transportation requirements. Our divers inspected the underwater portions of both bridges, obtained digital photos above and below water, measured and plotted streambed profiles, and completed the underwater inspection reports in the Michigan Bridge Inspection System.

Silver Road over Lobdel Lake required special access to complete the underwater and routine bridge inspections. The bridge is integral with an abandoned dam and adjacent to an active spillway. At the south or upstream fascia of the bridge, two gates and a curtain wall block access to the deck underside and abutments. The Road Commission hoisted the gates open so Ayres’ diver could swim through the opening to complete the underwater and routine inspections.

The diver inspected the abutments, curtain walls, concrete floor at the stream bed, reinforced concrete girders, and deck underside. Underwater and above water video was obtained that included dictation from the diver and the topside equipment operators. Notes on the condition of the above-water components were provided to the Road Commission. Ayres completed the underwater inspection report in the MBIS.

• Underwater Bridge