SR 80 Bascule Bridge Replacement

This project consisted of the replacement of the SR 80 (Southern Blvd.) Bascule Bridge and Tide Relief Bridge over the Atlantic Intracoastal Waterway, along with roadway improvements from Washington Road to A1A (South Ocean Blvd.). A temporary lift bridge was installed to accommodate traffic while the bascule bridge was being replaced. The scope also included roadway and drainage improvements, bulkhead walls, retaining walls, aesthetic lighting, and pedestrian safety enhancements. The temporary bridge was redesigned in-house and managed as a design-build project.

The new bridge over the Intracoastal Waterway was an 11-span, 948-foot-long structure featuring a 228-foot dual rolling leaf bascule span. The approach spans were built with five-span continuous concrete slabs. The Tide Relief Bridge was constructed as a seven-span continuous concrete slab. To maintain traffic flow on the narrow causeway, the structure was built in two phases. The approach piers were supported by 48-inch drilled shafts, while the bascule piers were supported by 60-inch drilled shafts.

All construction was performed from barges within a highly sensitive environmental area, where precast soffit forms were used instead of cofferdams to construct the pier foundations, enhancing safety throughout the construction process.