Hot Spot: Beaches
Many factors play a role in beach erosion on Florida’s Atlantic and Gulf coasts: Storms, coastal development, river dredging and dams, jetties and inlets that divert sand. But rising seas magnify the effects of the other factors. This year, more than 398 miles of beaches, or about half of the beaches in Florida, are deemed “critically eroded,” says Florida Department of Environmental Protection spokesperson Dee Ann Miller.
Florida spent $393 million in matching funds on beach renourishment programs in the last 10 years to put sand back on beaches, some of which was paid for by federal funds. It’s not just an aesthetic preference. Beach renourishment is one issue environmentalists and economic developers agree on. Wide beaches are essential for marine life, such as sea turtles, and for the state’s $72-billion tourism industry. Adding sand and dunes onto beaches is also one of the best protections against sea level rise.
Just south of Tampa Bay, Anna Maria Island lost 348,000 cubic yards of sand during Tropical Storm Debby. The Army Corps of Engineers estimates it will cost $20 million to restore the beach there, with $13.6 million coming from the federal government and $6.4 million from Florida and Manatee County. The federal, state and local governments split the check for beach renourishment, though the federal government typically pays a majority of the cost.
The state plans to spend a total of $37.5 million on beach and dune restoration in Florida this year, a 72% increase from the year before. In years following major hurricanes, the budget for beach renourishment can triple or quadruple. As sea level rise accelerates, the costs will escalate, too.
An estimate put together in 2008 by the Environmental Protection Agency says the cost of replenishing Florida’s beaches after 1½ feet of sea level rise is $1.7 billion. Sea level rise of that magnitude could happen as early as 2040, though most estimates say not until closer to the end of the century.
Hot Spot: Singer Island
Walling Off the Sea
Palm Beach island directly to the south of Singer Island is ritzier and more famous, but the half-mile-wide, five-mile-long Singer Island, actually a peninsula, is home to plenty of wealth. High-end properties such as the Ritz-Carlton line the beach, along with condo buildings, where units sell for upward of $1 million.
In recent years, residents of the 22-story Corniche condo in northern Singer Island have seen their beach shrink, in part from storm damage and in part from nearby Jupiter inlet, which sends sand away from the northern part of Singer Island.
Sea level rise also is a factor. In 1974, the highest tide recorded at the nearby Lake Worth pier was 4.15 feet above the average low-water line. By 2012, it was nearly a foot higher at 5.07 feet. The average sea level also crept steadily higher, rising by a more modest four inches.
Today, when storms arrive on Singer Island, the beach in front of the Corniche condominium is reduced to a sliver of sand. “We were very close to having to evacuate” during Tropical Storm Sandy, says Don Gaertner, who is on the Corniche’s condo association board. He’s survived a number of storms in the 10 years he’s lived at the Corniche but had never seen the water rise so high and obliterate so much landscaping as during Sandy.
The residents of the Corniche and five other condo buildings have chosen to fight the sea by spending $1.6-million to build a sea wall — 459 feet long and 19 feet high. They’ll foot the bill through a one-time assessment of $15,000 apiece. “There is nobody in our building of 110 owners that wants to build a sea wall and spend money to protect our shoreline,” Gaertner says. “But we have no choice because one more storm, one more hurricane and we will have to evacuate.”
Building sea walls and dikes in an attempt to hold back the ocean may be a logical strategy for some areas of Florida that will have to cope with rising seas. But the problems only start with the expense. Sea walls can accelerate erosion and destroy sea turtle habitats. They also invite litigation from environmental groups wanting to protect marine life.
Long term, because of Florida’s geology, sea walls may not be able to hold back the sea because Florida sits on porous limestone rock. Water will penetrate inland no matter how high a sea wall is built, says Leonard Berry, director of the Florida Center for Environmental Studies at Florida Atlantic University.
Gaertner says he understands it’s just a “Band-Aid” and not a long-term solution. It becomes a short-term economic decision — spend a little to protect your home and investment or lose everything if the next storm surge floods the Corniche.
Hot Spot: Marco Island
A Green Solution?
At the south end of Marco Island, just south of Naples, are 270 acres of mangroves that are dead or sickly. They are dying because of too much water. Man-made structures like roads have disrupted the natural flow of water through the mangroves, causing the mangrove acreage to fill up like a bathtub.
Mangroves, which thrive in saltwater, serve as natural barriers to storm surges. “We need natural defense for natural disasters,” says Chris Bergh, a scientist and the Nature Conservancy’s south Florida conservation director.
Beach dunes and oyster reefs are other examples of natural barriers to sea level rise. While in the past mangrove restoration was primarily done to protect animal and fish habitats, it’s increasingly seen as a cheaper way to protect against sea level rise.
Marco Island has decided to restore the mangrove forest in order to keep roads from flooding during storms and also to protect the wildlife habitats, says Robin Lewis, a mangrove expert hired to restore the Marco Island mangroves.
Lewis will build culverts beneath roads to allow water to drain. No replanting should be necessary, he says, as the mangroves will replant themselves.
The Marco Island project will cost $675,000 and take about 60 days. Typically, mangrove restoration costs about $50,000 per acre to $100,000 per acre, Lewis says.