Living Shorelines lead to healthy coastlines

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By Jenna McKenna

Forget everything you know about seawalls and shoreline protection.

As a little thumb of rock and fill jutting out into the Gulf of Mexico, Cedar Key knows enough about shoreline erosion to write a book.

But for generations, the best solution people could find to keep their yards from slipping away was to throw some concrete on the problem.

That mindset has already changed, as evidenced by the way the city's land development code reads. Property owners can only build a bulkhead or seawall to replace an existing one where there is a structure to be protected, and then only if they've exhausted all other options for shoreline protection.

Recent showdowns in City Commission meetings have shown that many people don't know yet, or haven't been persuaded, that there are other, possibly better ways to prevent shoreline erosion and protect structures from storms.

There are.

Three agents from UF-IFAS Sea Grant Extension recently visited the Marine Lab in Cedar Key to talk about a program called Living Shorelines, which practices softer, and in many instances, more effective shoreline protection than hardening solutions.

Chris Verlinde, of Santa Rosa County, Brian Cameron, of Bay County, and Scott Jackson of Okaloosa and Walton counties made a series of presentations on the types of shoreline protection that can be used in lieu of total hardening.

Cameron made the point that in a situation where a property owner is surrounded by hardened shorelines, a soft shoreline may not be effective because of the much stronger wave action caused by the hard shorelines on either side.

"There will be too much energy and you're likely to lose the installation," he said.

Existing seawalls are the biggest caveat to those considering using a living shoreline.

Living shorelines, as Verlinde pointed out, provide habitat for shore creatures and help trap sediments in runoff.

For one thing, this helps increase available soil and slows erosion; for another, it filters and cleans the runoff before it enters estuarine environments where recreation and edible shellfish operations may occur.

Verlinde described a variety of living shoreline installations, from a totally soft shoreline to a hybrid one with some hardened elements.

The choice between these types should be informed by knowledge about, among other things, the slope of the shoreline and the fetch (distance before breaking) of the waves.

Shorelines with a long fetch may benefit from having some randomly-placed hard objects a short distance offshore.

These objects will help dissipate the energy of the waves, which would otherwise build to an unmanageable peak, before breaking and tearing away the softer living shoreline elements.

Cedar Key has been working on a living shoreline project since May, trying to restore the northwest side of Atsena Otie where several storm seasons have torn away the shoreline and exposed the foundation of one of the cedar factory buildings.

Working in concert with the derelict clam bag project, IFAS, SRWMD, Cedar Key Aquaculture Association, Levy Soil and Water, and Cedar Key FFA joined together to create a planned oyster reef offshore, while planting spartina grasses and black mangrove seedlings onshore.

Before the installation could be completed, it was damaged by several days of heavy wind and strong waves. However, planners expect that the shell reefs, once fully in place, will be more effective than before and will enable successful replanting of the shoreline.

Jackson finished with a presentation on a the Grasses in Classes program, which helps involve schoolchildren in coastal conservation by having them grow and care for marsh grasses.

One project he oversaw, in Clearwater, was partnered through the organization Tampa Bay Watch.

Students at Countryside High School took grass plugs from a donor site, planted them in nursery trays, and cared for them through the year, dividing them at least twice.

More than four acres of shoreline could be covered with one program's output, and the number of plants more than triples during the year.

The presenters, along with city and CKAA host Sue Colson and local IFAS host Leslie Sturmer, noted that although living shorelines are probably the best shoreline protections and should be the way of the future, there is a lot to be unlearned both on the individual level and at the regulatory level.

For instance, although the reuse of shell piles is beneficial for creating oyster reefs and breaking up wave energy, shell piles have previously been abused as fill to inappropriately create more land. Thus, the use of shell in certain locations below mean high water is currently prohibited.

The bottom line is, living shorelines and wetlands are the best line of defense against storm surges, a fact not lost on New Orleans residents. The promoters of living shorelines hope to bring that understanding to all coastal inhabitants, to their benefit.