Laconia Main Street Bridge Rehabilitation

Laconia, New Hampshire

Professional engineering services to evaluate existing conditions, repair, and replacement alternatives for the Main Street Bridge, the primary crossing over the Winnipesaukee River and predominant access in and out of the downtown area. The bridge consists of three distinct and separate bridge structures that each carries a City street (Beacon Street East, Main Street, and Beacon Street West). The three streets and bridge structures converge at a point to make one overall bridge structure at the street intersections. The Beacon Street East segment is a 137-ft, 80-ft-wide curved bridge, constructed in 1968. The Main Street segment is a 75-ft by 69-ft-wide structure, constructed in 1970. The Beacon Street West segment is a 137-ft, 70-ft-wide, curved bridge, constructed in 1968.

Services include: topographic survey and preparation of a base map; sampling of paint to be tested for lead; determination of needed repair or replacement for structural items; collection of data for two other area projects to evaluate recommendations and impacts on pedestrian safety, access, and egress; preparation of a Project Review and Compliance form; a bridge type study; evaluation of operation and equipment of the existing traffic signal at the Main Street-Beacon Street and the Main Street-Court Street intersections; engineering study; and preparation of preliminary and final bridges plans, estimates, and bid documents.

Recommended repairs include removal and replacement of the concrete decks and fixed and expansion bearing plates, cleaning and painting of all steel surfaces, repair or replacement of deteriorated stringers and concrete abutments and piers, replacement of all deck expansion joints and substandard bridge rails, and addition of new approach rails.