SR 1002, Section PAT (Adams Avenue over Tacony Creek)

The structurally deficient three-span stone masonry arch bridge which carries Adams Avenue (SR 1002) over Tacony Creek is listed in the National Register of Historic Places and has a unique stylistic combination. The arched section is recessed, the piers are pyramidal in shape; the parapet wall is constructed of smaller stones than the spandrel walls; and the parapets are capped with a course of unfinished, projecting stones.

Benesch provided permitting and design services for the repair and strengthening of the three-span structure by resetting and repointing stones and reconstructing portions of the stone masonry walls; removing fill inside the structure and replacing it with lightweight concrete; repairing bridge foundations; rebuilding existing wing walls that extend from the support abutments; and installing scour protection around the substructure. The successful outcome of this project resulted in PennDOT winning a preservation award from the Preservation Alliance for Greater Philadelphia.

Several unforeseen problems were encountered during construction. The extent of scour under the existing substructure units was not evident until construction began. A submerged timber cribbing was discovered. Due to the extent of scour, settlement and masonry cracking, construction of a concrete mud slab in each span was necessary to stabilize the arches and prevent their potential collapse. The contractor needed to dismantle and reconstruct the existing ring stones and spandrel wall and the upstream third of the arch barrel of Span 3. All of this work had to be completed in phases while passing the streamflow through one of the spans and temporarily supporting the spans.