Government officials are embracing the concept of a management plan to chart the future of Longboat Pass, the vital inlet between Anna Maria Island and Longboat Key.
A work session Nov. 30 at the Manatee County Administrative Center served as a summit on the pass, bringing together representatives from the county, Longboat Key, Anna Maria Island, the Army Corps of Engineers and several consulting firms.
The group is working “to put our arms around Longboat Pass,” said county natural resources director Charlie Hunsicker, who led the lengthy presentation on the past, present and future of the pass.
Hunsicker emphasized the multiple issues involved — navigation, beach erosion and beach nourishment.
Erosion at both Coquina Beach and Longboat Key is serious, said Longboat Key town manager Bruce St. Denis, who estimated Longboat’s northwest shore loses 40-50 feet a year.
“The pressure on property is great,” he said, adding that Longboat Key likely would begin an emergency renourishment program before Christmas.
Hunsicker said a request from Manatee County Commissioner Joe McClash to discuss the dynamics of the pass prompted the Nov. 30 meeting.
In October, the commissioner opposed a board vote approving a resolution calling on the U.S. Army Corps of Engineers “to help restore navigational safety in the federal channel in the pass that separates the southern end of Anna Maria Island and the northern tip of Longboat Key.”
Last week, McClash praised the move to develop a management plan for the pass and urged management plans for all area inlets.
Hunsicker said a Longboat Pass plan needs to address how changes to the inlet impact the shore, and how changes on shore or to beachfront structures impact the pass. An extensive analysis has been conducted, but consultants plan to use new technologies to develop new models for proposed options at the site.
“Wherever you dredge, there will be impact and there will be consequences,” said Brett Moore of Humiston & Moore Engineers.
In one analysis, researchers with H&M looked back 140 years at the evolution of the region’s inlets and identified multiple natural and human-made changes. Palma Sola Bay, which now flows into Longboat Pass, once drained into Anna Maria Sound and the entrance of Tampa Bay, for example.
The construction of a jetty at the south end of Anna Maria Island in 1957 impacted the region, but most significant was the 1993 mining of the ebb shoal.
The mining contributed to “progressive chronic erosion” on the north end of Longboat Key, said H&M engineer Mohamed Dabees.
Tom Campbell of Coastal Planning and Engineering, during the meeting, said additional modeling would show what could happen in the area with a range of options.
The Coquina Beach jetty is leaking sand, so consultants plan to look at what would happen with improvements to the structure — perhaps a screen to hold back sand.
Another option is to build a groin on the north end of Longboat Key to hold more sand at Beer Can Island.
A third option is to build a breakwater at the tip of Longboat Key.
Campbell suggested “an offshore structure that runs parallel to the beach that allows sand to be slowed down at that location. This is a solution that the state was anxious for us to take a look at for Amelia Island.”
Also on the table is dredging the Longboat Pass channel, and possibly changing the channel’s direction, an idea that needs to be studied to determine the shoreline impact.
Dredging the channel could yield sand to renourish Longboat Key and Coquina Beach shores, said Hunsicker.
While dredging at Longboat Pass is under review, the federal government has plans to proceed with several dredging operations in the year ahead.
Milan Mora, a project manager with the corps, said projects “in the immediate future” include dredging in Tampa Harbor, near the Sunshine Skyway Bridge, near the northern top of Anna Maria Island and at Jewfish Key “right on the Intracoastal proper.”
Mora said the sand from the projects would be deposited at the federally managed Egmont Key rather than on Anna Maria Island or Longboat Key, where renourishment projects are planned in the coming years.
The sand would be taken to Egmont for several reasons — the ship the corps hired is built to drop dredge material from the center of the boat, the sand from the Jewfish dredge would contain silt and permitting already is in place for the Egmont renourishment.
“Egmont,” Mora said, “is in real need of sand.”
To download a copy of documents related to the study of Longboat Pass.