Old North Branch Rd over North Branch River, Antrim, NH | 2011

Old North Branch Road over North Branch River was a critically deficient, 26-foot wide by 44-foot span, steel beam bridge with a corrugated metal and concrete deck founded on abutments constructed of dry laid cut stone and rubble masonry. The bridge was closed in September 2008 due to severe deterioration of all bridge components and abutment scour.

Quantum Construction Consultants, LLC designed an 80-foot long by 30-foot wide steel plate-girder bridge founded on cast-in-place concrete footings and abutments as a replacement structure.

The new bridge span was lengthened to relocate the abutments outside of the main river channel, thereby reducing stream velocity and improving the hydraulic capacity at the crossing. Cut stones from the old abutments were salvaged and incorporated into newly constructed site retaining walls to preserve the cultural landscape.

This project was funded by the Town of Antrim, Federal Highway Administration (ARRA related), and New Hampshire Department of Transportation.