A section of Florida Keys highway historically prone to wash out from storms and facing erosion from sea level rise could get added protection through a village-led breakwater project.
Millions of dollars were spent over the years on a section of highway near Islamorada’s Sea Oats Beach to address growing vulnerability from wave energy and erosion. Hurricane Irma in 2017 led to a washout of the highway on Lower Matecumbe Key, the sole evacuation and access route for residents south to Key West.
Several years ago, the Florida Department of Transportation spent $18 million on a project that raised U.S. 1 along Sea Oats Beach by 1 to 2 feet. Near the shoreline, crews also installed articulated concrete blocks and rip-rap to protect the road from washing away.
Before the road-raising project began, the Florida Keys Electric Cooperative relocated its power poles to the other side of U.S. 1. Once surrounded by beach, the poles were being encroached on by the Atlantic Ocean. During Hurricane Irma, waves battered the equipment, nearly pushing over one pole and requiring emergency repairs.
To significantly harden this section and avoid future vulnerability, FKEC installed new, improved poles on the opposite side of U.S. 1 between the Overseas Highway and a small side road on the bayside in 2022.
Now, officials with Islamorada are developing a project to install a living shoreline/breakwater at Sea Oats Beach. At a Sept. 8 meeting, Islamorada Village Council members approved resolutions to accept a $300,000 grant it was awarded from the state for the project, as well as an agreement with RES to conduct environmental permitting.
“This was the No. 1 project in the vulnerability assessment the village worked on for years,” said Peter Frezza, village environmental resources manager. “We have U.S. 1 right there, the most vulnerable part of U.S. 1 and a beach that has completely washed away.”
Over the past two years, Islamorada has worked with its consultant RES Florida Consulting, to complete a feasibility study and design a hybrid living shoreline and breakwater project in 2 to 3 feet of water off Sea Oats Beach. The study determined what it would take to install an artificial reef. Nadia Locke of RES told village officials at a March council meeting that the area was too shallow to meet permit criteria. A breakwater was deemed a more appropriate solution.
Frezza said the project intends to stabilize the shoreline and prevent further erosion from future storm surge impacts. In addition, the project incorporates habitat restoration and creation features that support water quality improvements, including seagrass and mangrove enhancement, while providing ecological benefits to native wildlife.
The conceptual design shows the use of reef arches placed over shell mounds, from about MM 74.85 to MM 74.4. It’s designed to reduce wave energy reaching the shoreline, protect the existing shoreline revetment and the U.S. 1 road and utility infrastructure from erosion and washout.
Reef arches were deployed at the Indian River Lagoon. The project brought more sand on the shoreward side of the structure due to lower wave energy, according to Patrick Shearer, RES senior engineer. Wave attenuation devices were recently deployed by the Florida Department of Transportation to protect seawalls along the South Fishing Pier’s access road at the Skyway Bridge in Tampa from persistent wave energy and erosion.
Before council members approved the resolutions to advance the project, Nancy Correia, a former marine biologist, told them the only way to move water away from U.S. 1 is to renourish Sea Oats Beach.
“I’ve lived in Florida all of my life, and every beach I’ve ever lived on from Clearwater Beach, Dunedin Beach and Indian Rocks Beach to here has renourished their beach. That barrier is not going to do us any good. You might as well wait for the parrotfish to poop enough sand out.”
In response, Frezza said the village can’t put sand there unless the road is moved.
“The ocean is on the road. We would need to move the road to renourish the beach. The sand is never going to stay there. The sea level’s rising,” Frezza said.
