Route 72 Manahawkin Bay Bridges
Award of Merit
Owner: New Jersey Dept. of Transportation
Lead Design Firm: WSP USA Inc.
General Contractor: George Harms Construction Co.
Long Beach Island’s sole highway connection with the mainland has been significantly enhanced via the six-year, $319-million project that rehabilitated the existing three-mile causeway and added a parallel structure. To minimize weight on the existing bridge’s foundations, the superstructure was lowered by 5 ft and replaced with structural steel. Staging equipment on barges enabled rehabilitation work to be completed a full year ahead of schedule.
The new concrete bridge, erected just 12 ft away, is a span-for-span match of its predecessor, down to the rounded shape of the pier noses and pier cap overhangs. Because of Manahawkin Bay’s shallow depth, construction of the new structure was carried out from temporary trestles. Drilled shaft foundations mitigated long-term scour concerns.
With in-water work prohibited for six months each year to protect marine habitat, the project team facilitated year-round construction by building temporary cofferdams around the piers. Other environmental mitigation measures included adding vegetation in an adjacent wildlife refuge and providing temporary and permanent nesting areas for a pair of peregrine falcons that has called the bridge home for many years.