Tropical Storm Debby was a nasty storm system than struck Gasparilla Island with 8 inches of rain June 27, 2012, but whose wind-driven waves appeared to do little damage onshore.
A joint study by the Gasparilla Island Conservation & Improvement Association and the Gasparilla Island State Park revealed an estimated $445,000 in damage was done by the 15-year storm to the seawall, which is located on state property. Roughly 35 attendees saw a presentation on the damages and costs of potential repairs Monday at the Boca Grande Community Center Auditorium.
It will take an estimated $450,000 to repair the damaged Boca Grande Seawall behind the Boca Bay Pass Club on state property.
The erosion of seawall security was severe, according a "Belcher Road Seawall Revetment" study done by the Humiston & Moore Engineers of Naples. A revetment is a facing of stone or concrete to sustain an embankment.
The seawall near the southern tip of Gasparilla Island behind the Boca Bay Pass Club is in "acceptable" condition for now but another good storm could breach it, according to the study. A breach would put the Boca Bay Pass Club and the historic Port Boca Grande Lighthouse & Museum, among other multimillion-dollar residential properties, at greater risk of flooding.
"What you're looking at is drastic changes - undesirable changes," said Ken Humiston.
Boca Grande Seawall assessment
1)Seawall is in "acceptable" condition.
2)Tiebacks are mostly gone.
3)Most of 630 feet of concrete caps have blown out.
4)Add 250 tons armor stones.
5)Improvements would not affect downdraft.
6)Upland fill would support seawall.
7)Estimated cost of repairs: $445,000.
SOURCE: Humiston & Moore Engineers of Naples
Word of the Week
Revetment: 1: A facing (as of stone or concrete) to sustain an embankment. 2: Embankment; especially a barricade to provide shelter (as against bomb fragments or strafing). First known use: 1779. Source: Merriam-Webster Online Dictionary.
The seawall has settled, which lessens its protective capability, and some buttressing rocks were even propelled over it during the storm, according to Humiston & Moore presenter Marc Damon.
Gasparilla Island State Park Manager Chad Lach said he has been fielding questions about the battered seawall ever since TS Debby.
"I knew something needed to be done," he said.
Misty Nichols, GICIA executive director, said Lee County is already working on a sand renourishment plan for 2014-15. But that will not fix the seawall.
Lach said his Florida State Park superiors already know the severe need for seawall repair. He could not say how quickly repair funds from the state could be accessed.
"I've put it on the top burner," Lach said. "I've identified the need."
Repairs recommended by Humiston & Moore Engineers include:
1, replace concrete caps on seawall and raise it to a higher level;
2, restore seawall to original specifications;
3, add 250 tons of armor stones;
4, add tons of fill behind seawall;
5, plant vegetation upland; and
6, rearrange shifted rocks to original design.
The seawall was last worked in 2003-04 when more than $300,000 was spent to shore it up. The proposed solution could stem any more seawall collapse threats for up to 50 years, Humiston said.
"This is a long-term solution," he said.
Construction could take six to 10 months plus whatever time is needed to secure necessary permits, Humiston said.
But all bets are off if a big storm hits before the seawall backing is renewed. Boca Grande Fire Chief C.W. Blosser called it correctly after TS Debby passed by.
Immediately after the storm, Blosser said coastal erosion was likely the worst of the damage to Gasparilla Island.
"It's back to the seawall in a lot of places," Blosser said. "We're losing the beach."
And the seawall.