The City of Fort Pierce marina was destroyed when Hurricanes Francis and Jeanne moved through the Florida’s Central East Coast in 2004. The marina includes a 21 acre outer boat basin in the Indian River Lagoon and is a vital component of the City’s waterfront redevelopment efforts. The City selected Tetra Tech to handle the design, marina reconstruction, expansion permitting, and construction oversight. Tetra Tech also coordinated with the Federal Emergency Management Agency (FEMA) on a public assistance grant to fund the replacement of the marina docks, and a hazard damage mitigation grant to fund the storm protection elements of the project.  The total construction cost of the project was $31 million.

I was very impressed by the breakwater habitat islands—I've never seen a proposal with such a well-designed net environmental benefit before; you really did a great job.

Alexis Meyer, NOAA – NMFS Protected Resources Division

To provide wave and current protection for the marina, Tetra Tech developed a 15-acre island breakwater system. The protection system includes an artificial island complex that serves as a first-line breakwater system and includes mangrove plantings, tidal lagoon features, and oyster reefs to enhance its structural stability and functional performance.  All of the environmental enhancements but especially the mangrove plantings enable the system to perform well under existing and adapt to projected sea level rise conditions by providing increasing resistance to wave activity.

The project site is on a dynamically active flood delta where tidal currents continually move the sand deposits. Tetra Tech’s design for the islands incorporated extensive numerical and physical modeling to configure the breakwater system so that it works in concert with the existing flow and sediment transport patterns.  The team conducted extensive surveys for more than 90 acres of project area, utilizing diver assessment and underwater video surveys to map seagrass, benthic, coral, and hard bottom resources. Tetra Tech provided construction oversight services, engineering inspections, water quality monitoring, manatee observation, mitigation components construction, and all regulatory required monitoring.

The island protection system also involves the beneficial reuse of dredged material, approximately 150,000 cubic yards of sand, to create the large island complex funded under FEMA’s hazard damage mitigation program. The development and approval of this project required close coordination with FEMA, the U.S. Army Corps of Engineers, and the Florida Department of Environmental Protection.

Tetra Tech also completed extensive planning, providing nine individual plans to cover monitoring, mitigation, and maintenance of the island protection system and its 21 acres of onsite environmental enhancements. Tetra Tech planned, permitted, and constructed off-site mitigation including scraping down of two spoil islands to provide marsh habitat, repairing prop scars in marsh areas, filling a dredged hole, and adding navigational signage to guide boaters around marsh areas.

Tetra Tech’s reuse of dredged material in the design and elements such as oyster reef substrate, mangrove plantings, dune grass plantings, and the provision for shorebird nesting habitat have both functional performance and environmental enhancement roles in the project design. The National Oceanic and Atmospheric Administration (NOAA) had designated the project site as Essential Fish Habitat. Tetra Tech designed the project so that the overall habitat improvements would outweigh the loss of sandy bottom habitat due to the islands’ construction. The island complex reduces current around existing and potential seagrass recruitment beds so that diverted currents do not scour out existing marine resources and provide a significant improvement in habitat due to addition of hard bottom and oyster reef substrates.

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