Longboat Key, FL Fast-Tracked Beach Restoration

Background

The Town of Longboat Key, FL, an island community spanning 10.2 miles of Gulf of Mexico shoreline in Manatee and Sarasota Counties, is renowned for its pristine white-sand beaches and tranquil waters. However, the coastal beauty is increasingly threatened by hurricanes and tropical storms which bring powerful waves and storm surges that erode beaches, degrade ecosystems, and compromise infrastructure requiring the Town to proactively implement a comprehensive beach management plan to safeguard its shoreline.

Approach

Since 2011, Foth has partnered with the Town as its coastal engineering consultant, providing design, permitting, bidding, construction, and grant management services for multiple beach nourishment and stabilization projects. In 2021, we served as the Engineer-of-Record and permit agent for the Town’s Beach Nourishment and North End Structural Stabilization Project. The larger project, constructed by Weeks Marine, Inc., involved the dredging of over 700,000 cubic yards of sand from a shallow borrow area 10+ miles from the beach site on Longboat Key, the transport of the sand via scow and tugout, and pumpout of sand to the beach. Our team also served as Engineer-of-Record for two different dredging and beach nourishment projects that excavated the ebb shoal channels of the tidal inlets at either end of Longboat Key (New Pass and Longboat Pass). The combined projects placed over 1M cubic yards of sand along five different segments of the shoreline.

In conjunction with the dredging and sand placement, the highly eroded north end of the island at Longboat Pass was stabilized with the construction of five T-head rock groin structures. Built in the vicinity of North Shore Road, these structures were built on top of 364 gravel-fill geotextile marine mattresses, 10,400 tons of armor stone, and 1,280 tons of mattress stone. The structures are designed to significantly reduce the erosional conditions at the north end of the island, while allowing some level of sand transport through the structural field, working with the natural ebb and flow of sand at the north end of the island.

Our team provided design, permitting, construction contract documents, bidding, contract management, construction observation, permit compliance, and post-construction reporting services for all aspects of the projects. With our grant management assistance, the Town was able to secure grants and reimbursements from the Florida DEP, Florida DEM, and FEMA to offset costs.

Results

The final execution of the project included completion of the rock groin structures and all three planned dredge projects, constructed during the same time period to best leverage the available dredge plant. Total cost for the combined projects came in several million dollars under budget and took only seven months instead of the originally anticipated three years. The work, conducted between March and October 2021, was hastened by the presence of contractors being used for similar tasks by other member jurisdictions.

Most recently, the Town and Foth collaborated on the New Pass Terminal Groin Rehabilitation Project, improving sand retention and reducing losses to New Pass. Following the severe impacts of Hurricane Helene in September 2024, Foth assisted the Town in a rapid-response project to renourish the hardest-hit segments of the shoreline. Today, Foth continues to support the Town in the post-Helene recovery of the beaches, developing plans to restore the balance of the shoreline and pursuing alternative stabilization in the most erosional areas. Together, these initiatives are working to preserve Longboat Key’s shoreline for generations to come.