The Trenton–Morrisville Toll Bridge was in urgent need of an overhaul to handle peak-hour traffic. The Delaware River Joint Toll Bridge Commission prepared a program to rehabilitate and widen the structure.
The commission selected WSP for design and post-design services, with Ammann & Whitney as a sub-consultant. The team found deficiencies in the bridge and approach roads and recommended a third northbound lane be built on the bridge. WSP prepared a master plan to meet projected traffic through the year 2030.
The project included:
- Widening the bridge deck from 67 feet to 82.5 feet and reconfiguring the South Pennsylvania Avenue and Route 29 interchanges.
- Widening the bridge ― without additional and costly new pier construction ― by using unique 21-foot-long concrete pier cap cantilever extensions, with rods anchored into existing pier shafts in the river.With no pier construction in the river, time, cost and environment impact were drastically reduced.
- Preparing designs for upgrading road pavements, drainage systems, the toll plaza and part of the bridge superstructure.
WSP's innovative approach to widening the bridge was recognized with several awards, including an American Council of Engineering Companies (ACEC) National Recognition Award, an ACEC/PA Diamond Grand Conceptor Award, an ACEC/NJ Honor Award, an American Society of Highway Engineers of New Jersey Project of the Year Award, a Building of America Gold Medal Award, an American Road and Transportation Builders Association Globe Award and a Professional Engineering Society of Mercer County Project of the Year Award.