Historic Bridge Rehabilitation: Coudersport Borough 4th & 7th Street Bridges

This project involved the replacement of the existing historic truss structure at Seventh Street over the Allegheny River with a new structure. The historic truss was relocated downstream to the Fourth Street location, placed on new abutments, rehabilitated, and used as a pedestrian bridge.

Larson Design Group (LDG) completed final design services, including structural and roadway design, permit coordination, extensive utility coordination for the truss relocation, structural analyses and strengthening of the historic truss for the relocation, and construction engineering services for both structures.

The new structure at Seventh Street consists of a 60-foot, single-span, prestressed concrete spread box beam integral abutment bridge with an 84-degree skew. The bridge has a 24-foot curb-to-curb with a 5-foot sidewalk on the left side. The bridge was designed with the PA Bridge Barrier to improve sight distance and match the new bridge on SR 6, just downstream of the new structure.

The historic truss structure was relocated approximately 1500 feet to its new Fourth Street location by a truck towed dolly system over borough streets. The existing open grid steel deck and stringers were removed from the bridge and replaced with a glulam timber deck. A new steel railing resembling a historic railing was added to satisfy current railing design standards and the memorandum of agreement between the Borough and the FHWA.

The project also involved the reconstruction of 900 feet of Borough streets, new storm sewer, and pavement base drain. Traffic during construction was accomodated utilizing a detour and a temporary bridge over the Allegheny River.

LDG coordinated with Coudersport Borough, PennDOT, PADEP, Potter County Conservation District, USACE, and six different utilities including overhead power, cable, and telephone lines and underground gas, water and sewer lines throughout the design and construction process.