Route 49 Salem & Alloway River Bridge Replacements

Today, Salem County is home to parts of Route 49, a 50-mile expanse of state highway serving regional industry and shore point vacationers alike. But the New Jersey Department of Transportation needed to replace two bridges that threatened to disrupt traffic on the vital route. 

Modjeski and Masters (M&M) first developed an alternatives matrix for each bridge replacement. We identified design alternatives that least compromised the historic nature of the bridges. Another consideration was to preserve historic considerations of the Route 49 bridge over Alloway Creek. Rather than build a new structure at another site, we recommended its replacement on the existing alignment. To meet this requirement, our engineers used a temporary bridge that served as a bypass during construction of the new short span bridge. For the Route 49 Salem River crossing, our technical experts designed a new medium span bridge on a parallel alignment. To allow for the expansion of maritime commerce, M&M designed the center span of the Salem River bridge to be readily converted into a vertical lift bridge. In addition, the substructure for this crossing was designed with large-diameter drilled shafts – the first of its kind to be used by NJDOT. Once completed, traffic was diverted onto the new bridge without delay.