Gulf of Mexico
Boaters cruise Dec. 2 past the Longboat Pass jetty at the south end of Anna Maria Island. Manatee County officials are discussing a rehabilitation of the structure, which was installed in 1957. Islander Photo: Lisa Neff

FL - County focuses on coastline, erosion control tools for 2022

Anna Maria Island’s coastline is covered in sand courtesy of 2020 and 2021 renourishment projects. So Manatee County is focusing on improving the tools that help keep the sand in place — as much as possible.

The beaches are constantly challenged by erosive forces of the Gulf of Mexico, county parks and natural resources director Charlie Hunsicker said Dec. 1, addressing county commissioners, staff and representatives from Longboat Key during a workshop in Bradenton.

To address erosion, some capital projects involve pumping sand onto the shore, renourishing the beach for recreation and habitat.

Other capital projects involve constructing or repairing structures intended to keep the sand in place, especially at Coquina Beach in Bradenton Beach.

Hunsicker joked to his audience that he should call Coquina Beach the “Coquina Causeway” because the area was built up as a causeway in the 1950s and “Mother Nature has never wanted it to remain.”

Erosion control structures at Coquina include the Longboat Pass jetty on the south end of the beach — the tip of Anna Maria Island — and a series of 20 concrete groins spaced about 250 feet apart.

“These are structures that, along with a healthy sand source, keep our beaches beautiful,” Hunsicker said.

But it’s time to reevaluate the tools, he added as he introduced a county contractor, Tom Pierro of Coastal Protection Engineering.

The jetty, made of a wooden crib with concrete pilings and limestone boulders, initially was installed in 1957. In 2012, geotextile tubes were added as temporary erosion controls.

Pierro said the jetty needs rehabilitation — sand flows through it, “stealing sand from Coquina Beach,” and the seaward end of the jetty is eroding, “there’s not much left of it.”

Pierro also identified issues with the Coquina groins, particularly the northernmost structures where caps are broken and rebar is exposed.

A stabilization study identified seven alternatives, including one that Pierro said emerged as a favored option — remove the groin field and build three 300-foot breakwaters.

The county also is working on several other projects related to erosion control and renourishment, including:

  • An assessment of managing a shoal in the Passage Key inlet off the island’s north end is underway that provides sand for renourishment.
  • Work to establish a 2-acre limestone boulder mitigation reef off Coquina Beach.
  • Work to create a half-acre recreational reef off Coquina Beach for snorkeling.

During the Dec. 1 meeting, there was no discussion of future renourishment projects, as sand-based projects were completed in 2020 and 2021.

“Anna Maria Island is full of sand right now, which is a great thing,” said Pierro. “Longboat Key at the north end has a lot of sand as well.”

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