Wire Road experienced frequent roadway overtopping that resulted in repetitive roadway damage on the northerly roadway approach. The existing, 16-foot diameter, corrugated metal pipe bridge was severely undersized and deteriorated at the invert. The Town desired to increase the hydraulic capacity of the crossing and raise the roadway to prevent future roadway damage and reduce the frequency of roadway closures.
Based on hydraulic requirements, QCC designed a replacement structure that utilized a 65-foot span, precast concrete NEXT Beam bridge deck, founded on steel piles with cast-in-place concrete pile caps. The roadway profile was raised approximately 3.75 feet at the low point to an elevation slightly below the 100- year flood elevation. The progressive NEXT Beam technology shortened the construction period significantly.
This flood mitigation/bridge replacement project was funded by the Town of Merrimack and the NHDOT Municipally-Managed Bridge Aid Program. The project was constructed during the winter of 2012/2013.