Crosstown Parkway Extension Design-Build Project
Port St. Lucie, Fla.
Owner: City of Port St. Lucie
Lead Design Firm/Structural/Civil Engineer: RS&H Inc.
Contractor: Archer Western Contractors LLC (Walsh Group)
Construction Engineering and Inspection: Consor Engineers LLC
Forty years in the making, the 1.5-mile corridor improvement project includes a signature 4,100-ft-long bridge across the North Fork of the St. Lucie River that combines pile supports with Florida I-beams and a cast-in-place deck. By creating a third crossing into Port St. Lucie, the new bridge helps relieve traffic congestion and provides an additional hurricane evacuation route.
Because of the corridor’s route across sensitive wetlands in Savannas Preserve State Park, the design-build team sought to minimize the effects of an expected contentious environmental permitting process by using geotechnical information obtained from adjacent river channels, along with data from a similar bridge project nearby. By obtaining subsurface borings from a temporary construction trestle as part of the overall project permit, the team of Archer Western Contractors and lead design firm RS&H eliminated the need for a separate task-related permit. Along with minimizing the project’s environmental footprint, the temporary trestle would also prove valuable in facilitating longer spans and improving overall construction quality.
Even so, resolution of a year-long environmental permit challenge proved to be the project’s last obstacle, and the team was ready to make up for lost time once work got underway in May 2017. A key time-saving measure—the use of more than 60 precast pile caps—required multiple mock-ups to perfect the casting process and ensure a perfect fit between piles and caps. Custom-made two-stage, two-tier templates ensured that each pile was completely plumb. The meticulous planning paid off; none of the caps required recasting or modification.
The project team complemented the new bridge with Florida’s first “superstreet” intersection, tiered landscaping and large towers at the approaches that feature a nature-themed tile mural and a sculpture. A new park beneath the bridge provides a trailhead to the parkway’s sidewalks and features an ADA-accessible canoe launch. Despite being interrupted twice by hurricanes, the project was completed two months early with no recordable safety incidents.