This week Reef Innovations, the worldwide contractor for Reef Balls is at the Restore American Estuaries conference. Shortly Jim McFarlane will be presenting Best Practices, using Reef Balls on Living Shorelines. Reef Innovations is sponsoring the poster hall.
“One of our projects, Morris Landing, seemed untouched by the hurricane; the sill structure looked as it did before and that’s the point of them,” Skrabal said, a coastal scientist with the federation.
The comparative studies or living shoreline treatments by The North Carolina Coastal Federation, shows the value of homeowners taking steps other than bulkheads to protect their shoreline from erosion during high energy events.
Prior to the hurricane I surveyed the site that consists of rows of Reef Balls that have oysters growing on the. The site also compares Shell Baggs, A freestanding bulkhead, granite riprap, and loose oyster shell.
It was great hearing they didn’t have any loss of shoreline at this site during the storm. A 360degree video of the Morris landing site is at http://www.reefinnovations.com/archives/4383
Article Retrieved from: http://www.coastalreview.org/2016/12/living-shorelines-withstand-matthews-force/
Living Shorelines Withstand Matthew’s Force
Third in a multi-part series
HOLLY RIDGE – When Hurricane Matthew approached North Carolina in October, many in the state – from scientists to casual observers – watched to see the effects on shorelines. Storm surge and increased wave action can visibly wear away the coast. How would properties with bulkheads fare? Or, for those with wetlands conservation in mind, would living shorelines deliver what they promised?
Living shorelines are designed to protect vulnerable marsh habitats. In the case of hurricanes, though, living shorelines are also meant to be filters of stormwater runoff and to mitigate the erosion caused by the water that inevitably comes with the storms.
Larry Jansen chose his home in Holly Ridge’s Preserve at Morris Landing in part because of water and coastal access. As a volunteer with the North Carolina Coastal Federation, he’s been watching the 310-foot living shoreline completed there in July as the fifth phase of an ongoing restoration project, and he returned to the site soon after the hurricane passed through.
“I couldn’t really see any impact at all,” Jansen said.
Living shoreline proponents say that’s no surprise.
“For the most part, these shorelines are behaving exactly the way we expect them to,” said Tracy Skrabal, a coastal scientist with the federation.
Living shorelines are generally made with a permeable sill, such as bagged oyster shells or rock, that follows the natural slope of the land, with marsh grasses and other wetland plants behind.
“When the water rushes up, there’s nothing impeding the flow,” Skrabal said. So, they are designed for the water to come in and go back out.
Although these observations are a good sign, there is more meticulous work being done in the aftermath of the hurricane. Carter Smith is a doctoral student at the University of North Carolina – Chapel Hill Institute of Marine Sciences in Morehead City.
“It started about a year and a half ago, with the goal of comparing how bulkheads, living shorelines and natural shorelines perform in major storm events,” Smith said of the research.
In the weeks since the hurricane, Smith has visited the project’s 30 study sites from Southport to Manteo.
At each, there are comparable shoreline structures that will face similar storm surge and wave energy. For the purposes of the study, living shorelines are those that have had some type of restoration work, such as the addition of marsh sills and aquatic plantings, and natural shorelines are unmodified. Both are compared to the hardened bulkhead type structures that are common along the coast. In the coming months, Smith will work on assessing the post-storm effects. Right now, though, she has made some preliminary findings.
“For the living shorelines, I would say there are no detectable instances of damage,” Smith said. For natural shorelines, there was measurable marsh erosion. “In some cases, a loss of over five meters (about 16.4 feet) from last year.”
Some bulkheads remained intact, but there are some stretches where bulkheads were damaged. Hardened structures such as bulkheads can fail in a number of ways during storms and the damage is often obvious.
“What we see is that the vertical surface of bulkheads is more susceptible to high-energy events,” Skrabal said. “And storm waves can scour away what’s in front of them.”
The same can happen behind the bulkhead, when saltwater overlaps the structure and weakens it, causing structural damage or collapse.
Smith’s project also includes conducting boat surveys along 100 kilometers, or about 62 miles, of North Carolina shorelines, taking photos and noting the location coordinates of damaged structures.
“I would say that at least 50 percent of the bulkheads we surveyed were damaged, from minor damage to full-on collapse,” Smith said.
A post-storm assessment is also expected to be released by the Division of Coastal Management, analyzing how sills, marshes and bulkheads fared during the storm.
For years, coastal conservationists have been championing living shorelines for protection of marsh habitat.
“When you look at bulkheads, they ecologically bisect the habitat,” Skrabal said. “Marsh needs sediment, and they (bulkheads) tend to starve them of that with erosion and wave energy.”
Conservationists also have been encouraging property owners to consider living shorelines for better, more sustainable protection of their property. But bulkheads are by far the most popular choice for property owners. A previous study from the Institute of Marine Sciences estimates that as much as 9 to 16 percent of the coast is protected with bulkheads, and permits for bulkheads are easier to obtain. Whereas, it can be more difficult, months-long process to get permits needed to install a living shoreline. Bulkheads are more expensive, though, and can cost thousands of dollars, depending on the length of the shoreline.
“And the cost of repairing bulkheads after storms is considerable, too,” Skrabal said. It is her hope that the example of how well living shorelines did during the storm will convince more homeowners to consider them rather than repairing or replacing bulkheads.
“One of our projects, Morris Landing, seemed untouched by the hurricane; the sill structure looked as it did before and that’s the point of them,” Skrabal said.
This resiliency is something Erin Fleckenstein, a coastal scientist with the federation’s northeast office, has noticed, too. She cited a homeowner at Silver Lake Harbor on Ocracoke Island who had a living shoreline built there this past summer.
“Before, they were facing considerable erosion, mostly due to ferry traffic,” Fleckenstein said. But the owner reached out to Fleckenstein after the hurricane and made a point of saying how pleased they were with the erosion control and how well the shoreline did.
YRSCB Participates in CBF Oyster Reef Building
|CBF Oyster Ball Reef Workshop, October 18, 2016
We met at the VIMS boat basin at 8:30 am on a beautiful autumn morning. Several participants were seasoned veterans of the process and quickly got to work disassembling reef ball molds from a previous build. The group, along with other volunteers and CBF members, were anticipating delivery of concrete at 10am and we were ready – but the truck had issues. After much waiting for our concrete, the bucket brigade began. We finished early with many hands making light work and even had time to help with stuffing concrete by hand into the smaller “lego-style” reefs designed for homeowners.
So what does CBF’s Virginia Oyster Restoration Manager, Jackie Shannon, think of YRSCB participation in this project?
See photos (courtesy of Pattie Bland, Karen Reay and Jim Tate) below and click on each photo to enlarge.
To learn more about why oyster reef balls benefit Chesapeake Bay, see Restoring the “Coral Reefs” of the Chesapeake Bay or contact Jackie Shannon, Virginia Oyster Restoration Manager, Chesapeake Bay Foundation, 804-832-8804
Creating a ‘living shoreline’ with Reef Balls
Updated 6:25 pm, Tuesday, December 6, 2016
STRATFORD — Jennifer Mattei crouched down along the low-tide shoreline at Stratford Point to scoop up a mound of inky gray sediment in the palm of her hand.
It is proof, the Sacred Heart University biology professor said, that her Reef Balls are working.
Meandering rows of the thousand-pound dome-shaped cement balls create an artificial reef. Each ball is punctuated with holes that allow the tide and small sea creatures through. Over the past couple years the reef, planted just off shore, has begun to not only stop erosion but reverse it.
“It’s working beautifully,” Mattei said Tuesday of what many in the field call a “living shoreline.”
It is estimated that sediment, up to four feet deep and 100 feet wide has disappeared along that swath of shoreline over the past three decades. The property is now owned by the DuPont Corporation and managed by the Audubon Society.
So far, surveyors periodically measuring the terrain estimate sediment about 12 inches thick has re-accumulated over the past two years behind the barrier — enough for Mattei to win another $115,198 grant to expand her work.
The just announced National Fish and Wildlife Foundation’s Long Island Sound Futures Fund grant will be used this summer, with the aid of a team of Sacred Heart students, to plant thousands of marsh grass plugs into the shore line upland from the barrier.
The pilot study began with 64 Reef Balls. This November, another 327 were added with the help of DuPont and the Army Corps of Engineers. Mattei checks on them periodically, searching for signs of algae, barnacles and any oysters who now call them home.
Reefs made of clinging oysters used to protect the shoreline. They disappeared centuries ago.
It was the oysters, the horseshoe crabs, the piping clover and all other habitat, Mattei admits, who got her into this kind of research. Those creatures depend on the shoreline and their access has been compromised by decades of beach erosion and climate change.
“The ocean floor is rising. Storm frequency is increasing. Global climate change is real,” Mattei said.
Seawalls don’t help. They hurt. When waves crash against them, sediment is pulled away from the shore and sea creatures lose access to the shore.
Mattei hit upon the idea of Reef Balls, which got their start in Florida to protect coral. The are made with a special cement formula that resists erosion and heavy enough to withstand hurricanes. The holes are positioned so that when a wave hits, the water shoots through more gently.
Although used worldwide, Mattei is believed to be the only one to use them in Connecticut.
Scientists like Juliana Barrett, with the University of Connecticut Center for Land Use Education and Research hopes that will soon change.
Barrett said state law now severely restricts the construction of traditional seawalls. Mattei’s project is a great example of an alternative.
“What she is doing is really, really important,” Barrett, said. “She is creating a living shoreline I hope will be replicated. She has the most extensive project going on.”
In addition to rebuilding dunes and salt marsh grass, Mattei said she also has her eye on sediment expected to be dredged next fall from the nearby boat channel at the mouth of the Housatonic River, which is on the opposite end of Stratford’s beach front.
Although some is earmarked for Hammonasett Beach in Madison, Mattei said, some directed her way would speed up her stabilization project.
“I hope this can become a demonstration site for what to do,” Mattei said.
Article Retreived from http://www.ctpost.com/local/article/Creating-a-living-shoreline-with-Reef-Balls-10778523.php#photo-12000856