Programs to Protect and Restore Eroding Shorelines
Editor’s note: This article first appeared in the June 2016 edition of Erosion Control.
The storm forces of rain and wind, to say nothing of tidal ebbs and flows, pose special problems in controlling erosion along coastlines. All of these forces affect the surrounding area—beaches, roads, bridges, homes, and other buildings—as well.
Rising sea levels in many locations add power to a storm’s negative punch. And when storm surges race many miles inland—as they did after Hurricane Katrina devastated New Orleans and the Mississippi Gulf Coast—then coastal erosion is magnified.
With their battering wind, rain, and storm surges, hurricanes are especially damaging to coastlines. Local, state, and regional officials have learned the hard way that the resilience needed to recover from a major storm—and to lessen erosion—has to be planned in advance.
“Katrina was the catalyst. We had had storms before [but not to that level]. It was the pinnacle, the turning point for adaptation planning,” says Rhonda Price. “But we have to be realistic. We can only do so much planning when Mother Nature is in control.”
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Price is the deputy director for the Office of Coastal Restoration and Resilience, part of Mississippi’s Department of Marine Resources (DMR). In this post she is actively involved with the Gulf of Mexico Alliance (GOMA).
GOMA includes about 150 scientists, government officials, and academics from the five states bordering the Gulf of Mexico. Its members share knowledge and resources to improve the environmental and economic health of the Gulf and its surrounding states.
GOMA has been an active partner in the Governors’ Action Plan for Healthy and Resilient Coasts I and II, created by governors of the five Gulf states. They have completed goals of the first two plans and are now starting work on Plan III.
GOMA has a broad range of activities, including administering grants for its research initiative, monitoring and observing conditions in the Gulf, and working on restoration after the Deepwater Horizon oil spill.
Regional planning is associated with the National Ocean Policy, which supports coastal and marine spatial planning in the US via nine geographic areas. Then there is GOMA’s successful Clean and Resilient Marinas Initiative.
Marinas play a significant part in the economy and lifestyle of any coastal area, serving as bridges between coastal shorelines and waterways. Their operations and the best management practices (BMPs) they have in place can help manage stormwater and prevent coastal erosion, thus improving the water quality.
GOMA members developed the Clean and Resilient Marina Initiative in part to increase regional storm resilience. The initiative’s educational programs and standards help owners and operators of marinas minimize the negative effects of severe storms.
Reflecting on recent GOMA programs, Price says, “The Clean and Resilient Marina Initiative has taken off. Other regions of the country are starting to be aware of the resilience component, such as the Governors’ South Atlantic Alliance, which is like the Gulf of Mexico Alliance.” GOMA, she says, is “working with them to adopt some of the BMPs. They looked at the framework we had created and decided that standard would be great to incorporate into Eastern marinas.”
Price says that GOMA has also started sharing information with people in the Great Lakes region who are involved in developing storm resilience, such as the National Working Waterfront Conference.
One example of a BMP that GOMA recommends for marina owners and operators is “having a hurricane preparedness plan,” says Price. “Most of them did not have a plan. If they had a plan, it was in their heads.”
She adds, “They learned that having a plan with evacuation procedures, preparedness, and proper signage went a long way to implementing the resiliency component. If they’re prepared in front of a storm they’ll go back to business faster in the back of a storm.”
Because of Hurricane Katrina, the Gulf Coast “lost 90% of our harbors and marinas,” says Price. Rebuilding meant planning for resilience during future storms. “Marina owners were asking, ‘What can I do to keep my downtime to a minimum and get back into business sooner?'”
One example of such planning was done by the owner of the marina in Bay St. Louis, MS. His new harbormaster’s office can be trailered inland before a storm (usually Category 3 or stronger) arrives and kept there until it passes. Then it is trailered back on site, and the marina is immediately ready for business.
Price points out another innovative resiliency strategy at this marina. “All of their power pedestals are secured by two bolts. Two turns of a socket wrench and they can be removed quickly,” then taken away from the storm’s path, and later reconnected quickly.
Building resiliency begins before construction starts. “It’s important for a new marina to look at design and site plan, at how siting the marina into the watershed will be. You have to look at historical storms and not face it into the south wind,” says Price.
Owners of older marinas along the Gulf Coast have learned that wood pilings don’t stand up to storms nearly as well as concrete pilings do. “Now when it’s time to renovate a slip or install any new component, they look at [our recommended] BMPs. The cost is more upfront, but it [concrete or other more durable material] will pay off in the long run. After a storm, they’ll be back in business more quickly,” says Price.
She points out a marina in Long Beach, MS, that was put out of business by a heavy rainstorm. “All the slips are under renovation. The wood pilings are being removed, and the owner is going with more sustainable material.”
Price admits that while GOMA’s standards are voluntary, “the owners want to promote their marinas as being environmentally responsible operations through using these BMPs. We’ve given them the opportunity to use the resources.”
Having a clean and environmentally friendly marina attracts business, but Price says that the owners and operators also “want to be environmentally responsible stewards and protect coastal areas.”
She notes that GOMA’s goal in setting up the Clean and Resilient Marinas Initiative is giving marinas resources. “We’re not going to prevent storms, living on the coast. We’re going to have to endure these coastal hazards.”
Price foresees GOMA “over the next year or two turning our projects into models. We [would] act more in a technical or advisory way. We could pull expertise from our members, have our resilience people go into communities and advise them.”
GOMA’s scientist and academic members, she says, “could produce some really groundbreaking science that would really empower decision makers in communities. But if they’re not educated or informed by the scientific findings, it’s a waste of energy. We have to bridge that gap between the two entities,” says Price.
She notes that resilience has now become a buzzword, but people don’t always think about the meaning behind it. “As one of our team members said, ‘I don’t want to bounce back to where we were before the storm. I want to go forward, to better things.'”
Melissa Pringle is a senior principal scientist at Allen Engineering and Science in Jackson, MS. Through work with private and public clients, she has noticed an increased awareness and interest in improving resiliency and reducing coastal erosion in the Gulf Coast region.
“In addition to looking at adapting green infrastructure and sustainable development practices, the coast is exploring adaptive shoreline management, and the state has developed a general living shoreline permit to make permitting easier and quicker,” says Pringle.
Economic recovery from coastal storms is inseparable from physical recovery. Pringle says one new development that will help here is the Oyster Council, established by the governor of Mississippi. The initiative will spark new technology and practices and share techniques to increase oyster resources for the state.
Credit: OREGON COASTAL MANAGEMENT PROGRAM/DLCD
South Oregon coast
Another development is the increasing attention to nature-based tourism. Storm resiliency at hotels, marinas, and other visitor-related businesses and prevention of erosion at beaches and other attractive coastal locations help keep the tourism industry strong.
As for trends and interest in particular BMPs to lessen coastal erosion, Pringle says, “Living shorelines and green infrastructure are getting more attention and gaining traction.” When she talks to public officials about managing stormwater and preventing shoreline erosion in their communities, she senses a more open attitude toward green infrastructure. “Local municipalities are exploring green infrastructure, adaptive management solutions, master plans, and resilience guidelines,” she explains.
As an example of this inclusion of green infrastructure, Pringle mentions a city that developed an urban waterfront park master plan. The project “included identifying and removing invasive species along the marsh bank and creating a marsh and wetland restoration planting area along either side of the stream channel running through the site. It also involved creating a rain garden at the corner of the parking lot to reduce pollutants, and creating educational interpretive signs located around the park.”
Pringle says that another local municipality took a very inclusive approach in its planning for storm resiliency. This Gulf Coast city “developed a comprehensive and proactive plan for short-term and long-term needs of the city and its residents. The city’s planning included the development of new ordinances, ordinance amendments, process improvements, subdivision plat reviews, and commercial design reviews.”
“Local municipalities are conducting advance planning for climate conditions, focused on analysis of infrastructure needs for increased storms and potential sea level rise. They are training of staff and planning commissioners on tools for decision-making with resiliency at the forefront,” says Pringle. She also sees more training and workshops provided to city officials on strategies to promote resiliency.
On a regional level, she notes, “The Mississippi Alabama Sea Grant developed a Community Resilience Assessment and worked with various municipalities across the coast.” Various agencies and entities have created guides or “toolboxes” to help municipal officials and property owners in their storm resiliency planning. Allen Engineering and Science assisted the Mississippi Department of Marine Resources with the development of The Sustainable Development, Smart Growth, and Coastal Resilience Toolbox for Coastal Mississippi, available online at www.smartgrowth.dmr.ms.gov. This downloadable publication is organized according to five concepts based on smart growth principles: Community Character, Growing Green, Transportation Choices, Policy in Practice, and Coastal Resiliency and Natural Hazards.
Credit: OREGON COASTAL MANAGEMENT PROGRAM/DLCD
Twin Rocks area, Tillamook County, OR
The toolbox takes both a long-term and a short-term approach to increasing resiliency in coastal areas. It includes BMPs of great value that would take months or even years for a municipality to implement, as well as some that can be put in place much sooner.
The AllenES website also includes The Alternative Shoreline Management Guidebook, which was developed with the Mississippi DMR. This publication is a 28-page guide to help coastal property owners and municipal officials better understand shoreline erosion and how to prevent it. The guidebook clearly explains revetments, bulkheads, and other types of traditional hard-armor shoreline methods. It also describes various kinds of living shorelines and hybrid practices. It includes sections on permitting, a native plant list, and factors to consider when deciding how to protect a shoreline from erosion.
GOMA also works with the Coastal Storms Program (CSP). This national agency was developed by the National Oceanic and Atmospheric Administration (NOAA) to help communities reduce the devastating loss of life and property that costal storms can cause.
“We work hand in hand with them. NOAA members are part of our team,” says Price. “It’s a win-win situation.”
Through CSP, NOAA works with both public and private agencies. The work focuses on the greatest specific needs of a particular region and lasts three to five years, as needed.
When a region requests help, CSP first sends an outreach coordinator. The coordinator ensures that NOAA projects connect with projects being done by other groups or government agencies and helps create new partnerships focused on increasing resilience. CSP has helped communities in northeast Florida, the Gulf of Mexico, southern California, the Pacific Northwest, and the Pacific Islands. The program is now working in the Great Lakes region and, because of Hurricane Sandy, in the Mid-Atlantic as well.
Credit: ALLEN ENGINEERING AND SCIENCE
An example of a living shoreline: marsh grass at Keegan Inlet in Biloxi, MS
Local, state, regional, and federal agencies are not the only groups working to stem the tide of coastal erosion. Local residents who are concerned about their nearby marine environment have joined forces to monitor the beaches along Oregon’s coast. Members of CoastWatch adopt 1-mile sections of Oregon’s coastline. The almost 1,300 CoastWatchers walk their designated sections—some of them have had the same particular miles for years—and note changes caused by nature or man. They post their observations and cell phone photos online, in the same way that stormwater neighborhood volunteers in some communities do. In an age of budget shortages, the information they gather can be very helpful to coastal authorities and governmental agencies.
Other coastal regions of the country could develop similar programs with citizen scientist volunteers. Members of scout troops and environmental organizations such as the Sierra Club, as well as students performing community service projects, are possible volunteers.
In late fall and winter of 2015, CoastWatch members participated for the sixth year in photographing and documenting the highest tides along the Oregon coast. Their work was part of an international effort by volunteers recording the highest tides in Australia, British Columbia, California, Maryland, New Hampshire, New Jersey, Maine, and Washington state. These extremely high tides are commonly called “King Tides.” They occur when the moon is closest to the earth. Documenting exactly how far up the shoreline these super tides reach helps show the impact of sea level rise and predict the rate of erosion.
The King Tide marks are documented during the winter in this hemisphere because that is when storm surges, high winds, and waves are more frequent. That combination of the three elements results in even higher water levels.
Volunteers are encouraged to take photos at the same locations year after year, as that will make changing sea levels more easily apparent. Photos that show the King Tide mark in relation to a road, seawall, or building clearly indicate potential future threats. Comparison photos with regular high tide marks are also helpful.
Erosion is a steady factor along the Oregon coast. “We’re constantly getting that movement of waves, enhanced sometimes by El Niño,” says Phillip Johnson, director of the Oregon Shores Conservation Coalition. “We also have the second-highest measurement of wave energy. The ocean along the eastern coast of South Africa has the highest. Wave heights are increasing. That’s a trend that measures back to the 1940s. Peak storm wave heights are getting higher and higher,” he adds.
Johnson laments that “storms are getting more intense, and most erosion happens during storms.”
Oregon’s 1967 Beach Law (a revised, more specific version was passed in 1969) makes the state’s entire coastline a free, accessible public beach. People can be anywhere along the shoreline. But protecting the beaches is complicated, because much of the development happened before people understood much about coastal hazards and erosion. Property owners may want to protect their land by armoring it, but they can’t if doing so encroaches on the public beach area closest to the ocean.
Some Oregon beaches are subject to littoral cells. The majority of the heavy winter storms come across the Pacific from the west. They scour sand from the southern ends of headland areas that jut into the ocean. In the summers, gentle winds from the north push some of the sand back south.
Johnson explains that Oregon’s coastline is affected by two types of erosion. One type “happens bit by bit, and it is increasing in many areas. That said, an El Niño can, during the six months or year it is active, raise sea level height by as much as six inches.”
He continues, “We’re having an El Niño this year. An El Niño year can swamp that slow, steady increase in erosion.”
Another factor that influences erosion is the Pacific Decadal Oscillation. Operating in a roughly 20-year cycle, this recurring pattern of ocean atmosphere climate influences ocean depths and other factors that affect erosion.
“There is not nearly enough interest in living shorelines” that could help protect some coastal areas, says Johnson. He thinks that in the long term, the only solutions are to reduce the use of fossil fuels and “to pull back on property development,” not allowing it so close to the shoreline.
Laren Woolley is a coastal shorelands specialist with Oregon’s Department of Land and Conservation Development. Woolley notes the cyclical nature of coastal erosion. “The last three to four winters have been extremely mild with limited coastal erosion. During this time our beaches have experienced increased sand levels generally that we have not seen in most places since the last super El Niño/La Niña events of 1997 and 1998.”
That gain has been lost. “However, this year a series of large winter storms and high-water events have once again significantly reduced sand levels on our beaches. If this continues throughout the remainder of this winter, we likely will see significant increases in coastal erosion.”
Woolley is not optimistic about slowing erosion. “Long-term forecasts indicate the potential for increasing chronic coastal erosion over time.”
Sometimes the best protection against erosion after a storm is a hard BMP. A rare early season storm, Hurricane Dennis hit the Panhandle region of northwest Florida in July 2005. One of the most damaged areas was Franklin County, which is about 80 miles from Florida’s capital city Tallahassee.
Measuring 545 square miles, Franklin is one of Florida’s largest counties by area. It is also one of the least populated, with 11,000 residents. Apalachicola is probably its best-known municipality.
Hurricane Dennis caused major damage to the Gulf of Mexico coastline in Franklin County. As time passed, the beach continued to erode along State Route 30/US 98, a major coastal highway. This essential road for tourists and residents was in danger of sinking and even collapsing. Franklin County needed to have the road repaired as quickly as possible.
Soon after Hurricane Dennis hit, President George W. Bush declared Franklin County one of 13 federal disaster areas in Florida. The county then became eligible for the Federal Emergency Management Agency’s (FEMA) Public Assistance funds to help restore or rebuild essential public facilities. This wave protection project was funded by FEMA.
The repair project was designed to stabilize the beach and protect the stretch of road adjacent to St. George Sound, which is close to Apalachicola Bay. This bay, which connects to the Gulf of Mexico, provides more oysters than any other location in Florida.
Officials with the Florida Department of Transportation (FDOT) and Franklin County chose the ArmorFlex shoreline reinforcement system for the project. Contech Engineered Solutions of West Chester, OH, is the manufacturer.
ArmorFlex comes in various widths and lengths, making installation flexible and more easily done. Its interlocking concrete blocks have a high per-unit weight for their size. They’re heavy enough to provide erosion control under wave conditions.
The ArmorFlex revetment system comes in either closed-cell style or with a 20% open area that allows for vegetation and encourages wildlife habitat. The blocks are laced longitudinally with galvanized steel, stainless steel, or polyester revetment cable.
In October 2008, 647,019 square feet of ArmorFlex Class 70 were installed between the beach at St. George Sound and State Route 30/US 98. The project was done under the direction of FDOT, which also did the required engineering work. The contractor was Phoenix Construction Services of Lynn Haven, FL.
Controlling or even slowing coastal erosion isn’t a matter of a few easy steps. It helps to understand which BMPs are most effective—as well as cost-effective—for a particular geographic area and climate.
Thinking regionally and sharing information are also essential. Short-term solutions and pilot projects are needed, but so is ongoing research for long-term solutions
To continue reading the full article check out the June edition of Erosion Control.
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