Working as the prime consultant, SGH managed the bridge inspection, including an above-water bridge assessment and an underwater inspection of the damaged stone-masonry pier. We analyzed the structure, considering the damaged pier and deteriorated wood components. SGH concluded the bridge was unsafe and prioritized repairs to meet budget and schedule constraints.
As part of our rehabilitation program, SGH developed a solution to encase the central pier, which was missing large portions of masonry. Our encasement design included a reinforced concrete jacket and fieldstone form-liner finish with a stone riprap revetment around the pier base. We also specified replacing deteriorated wood decking to match existing, installing a new railing to meet current code requirements, and waterproofing sleepers between the steel beams and decking for durability. We recommended future repairs to address minor deterioration of the abutments and steel superstructure.
The construction team employed environmentally sensitive techniques, including a floating turbidity curtain around the work area and a portable cofferdam system at the pier to limit disturbance of the river bed and provide dry site access. SGH performed construction administration services, including site visits, review of shop drawings and contractor submittals regarding proposed construction methods, and management of environmental permitting in collaboration with our subconsultant.
With a scope limited to immediately needed structural repairs, the contractor completed the work in just three months and the Department of Conservation and Recreation used remaining funds to upgrade trails leading to the bridge.