The Putney STP DECK(38) project will replace the existing bridge deck, which has non-crash tested bridge and approach rail, with a new bridge deck that meets current design standards. The existing structure is a single span cast-in-place deck on rolled beams constructed in 1954. It is approximately 54 feet in length and 32 feet wide. It features concrete parapets with a metal handrail along with an adjoining sidewalk. The bridge deck is in ‘fair’ condition while the superstructure and substructure are in ‘good’ condition. VTrans bridge inspectors have observed areas of heavy saturation, cracking, and efflorescence in the deck which is evidence of significant concrete deterioration. The bridge is owned and maintained by the State of Vermont.

VTrans evaluated several alternatives to preserve and extend the service life of the Putney US Route 5 Bridge 15 in an engineering study completed in January 2016. The study assessed the proposed design criteria for lane and shoulder widths, safety criteria and historic requirements. Several alternatives were considered including, no action, concrete deck patching and a deck replacement. The study also considered a number of traffic maintenance options such as a short term bridge closure and phased construction. The engineering study recommends replacing the existing bridge deck and bridge approach rails while traffic is maintained on an offsite detour for a 14 day short term road closure. This innovative approach will minimize impacts to right-of-way, utilities and environmental resources as well as minimize traffic disruptions while increasing the safety of the traveling public and construction workers.

The new bridge deck will be constructed using cast in place concrete. The new bridge deck will be the same width, provide a greater load carrying capacity and feature a historic bridge rail that meets safety criteria and ties into the surrounding environment. By applying this cost-effective treatment at the right time, the useful life of the structure will be extended another 30 to 40 years. This provides the largest benefit for the lowest cost when compared to the other bridge treatment alternatives.