Rehabilitating a Historic Wooden Covered Bridge to Carry Modern Truck Loads with No Visual Impacts to the Structure

In November of 2007, Pennoni Associates was awarded a historic wooden covered bridge rehabilitation project by a State Department of Transportation. Originally constructed in 1866, the historic covered bridge is listed on the National Register of Historic Places and spans 104'–6" over a state classified scenic river. The original scope of the project included removing and replacing deteriorated wood members as well as repairing the limited capacity steel superstructure that had been installed in 1977 as part of a bridge rehabilitation project. During preliminary design, the project scope was expanded to include replacing the existing superstructure with one that is capable of carrying current LRFD AASHTO live loads and providing a geotechnical analysis to identify abutment and subsurface design parameters. All the proposed project work required review by the State Department of Transportation as well as the State Historic and Museum Commission for authenticity compliance. The proposed work was not permitted to visually alter the appearance or historic character of the bridge. Currently the project is in the final design phase with construction anticipated for the spring of 2010.