The authors describe the design development process of the $840 million (Canadian dollars) Northumberland Strait Crossing Project from conceptual design in 1987 to the final project design. The 13 km 8 mile) long bridge links Prince Edward Island with New Brunswick and mainland Canada. The current design is based on main bridge spans of 250 m (820 ft) to minimize the number of piers and foundations in the Strait. Each span consists of a continuous precast, prestressed concrete variable depth double cantilever girder with a length of 190 m (623 ft) and a drop-in segment of 60 m (197 ft). The design took into consideration unusually heavy vehicle loads, high wind loads, seismic factors, very high icepack forces and possible ship collisions. Precast concrete production began in the summer of 1994 and the main spans will be erected beginning in September 1995. The project is scheduled for completion in the summer of 1997.
