The town of Longboat Key is working on four beach renourishment projects throughout the island.
Town staff and a coastal consultant are evaluating potential long-term impacts from Tropical Storm Eta before embarking on a yearslong plan to renourish the beaches.
“They’ve indicated that there are some areas of concern,” Town Manager Tom Harmer said. “When you do this assessment, you have to look to look at, not just which sand may have been impacted through the erosion from the storm, but they look at the entire beach profile, which goes out into the water to see where did that sand go?”
Harmer said in some cases sand might have moved on the island and in others, the sand might still be in the water.
“You can look at it a day or two after the storm, but you have to kind of take a little longer view to see where that sand may end up,” Harmer said.
Before Eta passed through, Longboat Key projects manager Charlie Mopps updated commissioners about four beach projects the town is working on: emergency dredging at Canal 1A, Greer Island spit management, beach renourishment, and the New Pass groin maintenance.
Here is an overview of the projects:
Specifically for Canal 1A on the north end of the island, the town plans to dredge a 300-foot by 30-foot channel adjacent to the Greer Island spit. The dredging will restore tidal flushing and limited boat access.
The town is reviewing three bids on the project, ranging between $81,755 and $120,000.
“Right now, we’re reviewing the qualifications of the lowest responsive responsible bidder,” Mopps said.
The notice to proceed is expected in December with construction anticipated to start between December and March 2021.
Greer Island spit management
This project proposes a 15-year permit with dredging and sand placement every four to eight years on an as-needed basis. It also proposes initial dredging of about 25,000 to 35,000 cubic yards from the spit, which is north and east of the Longboat Pass bridge.
Mopps said the town wants to restore this area to the 2003-2006 conditions.
The permitting application process takes up to a year, according to Mopps.
Construction on this portion of the project would start around December 2021 and take about four months.
This project would have a contractor excavate, transport, place and shape 810,000 cubic yards of beach-quality sand from offshore borrow areas to Longboat Key’s Gulf of Mexico shoreline.
A typical dump truck holds about 10-14 cubic yards.
The town is planning to advertise for bids in December with bid opening in January 2021.
The notice to proceed is expected in February 2021 or March 2021. Construction time will take at least six months as the winning bidder must complete the project outside of turtle season, which happens each year between March through October. Mopps thinks the town could move up the project.
“We need to buy as much time as we can for our contractor to work outside of turtle nesting season,” Mopps said.
New Pass groin maintenance
This project is to permit, maintain and repair the groin at New Pass on the south end of the island. The plan calls for dredging about 200,000 cubic yards of sand out of New Pass.
The material would be placed on the beaches just north of New Pass and fill southern segments of beach not nourished during the current project.
Design and permitting are scheduled for fiscal year 2021 with construction in the winter of 2022.
It will take about four months to complete this project.
Mopps said the costs of this project would be “minimized” because of the short distance where the sand would be put into place.