A Living Shoreline replaced a
failing bulkhead at the N.C. Wildlife Resource Commission's Edenhouse
boat ramp on the Chowan River.
Our Coastal Marshes and Erosion
The salt marshes that fringe our coastal waters are some of the most productive and valuable natural habitats in the world. They provide food and shelter for many creatures and are critical nurseries for important marine species. The vast fields of marsh grasses filter pollutants from runoff and protect the land from storm waves and tides.
But our marshes are under assault every day. Daily tides, waves from storms, boat wakes and a relentless rising sea eat into the marshes, which can only respond by yielding and moving back.
Until we throw walls in their way. People who build close to our marshes are also affected by erosion. Instead of moving back, most respond by building wooden or concrete walls or throw down piles of rock to protect their property. Locked in place in front of the wall or rocks, the marsh can't retreat and will eventually disappear. As many as 20 miles of the state's estuarine shoreline are legally walled or rocked each year.
Our Living Shorelines Work
A Better Way
At N.C. Coastal Federation we maintain that the best way to deal with erosion is to plan for it, to build as far as possible from the water's edge and to retreat when the time comes.
When that's not possible, the federation recommends using stabilization methods that maintain the natural integrity of the marsh and do the least damage to them. Living shorelines are one such approach.
What are Living Shorelines
Livings shorelines use as many natural elements as appropriate for the site to protect the shoreline from erosion. The federation and many other organizations consider this method a better alternative than traditional bulkheads or walls. While bulkheads reflect the wave energy back along the shoreline exacerbating erosion, living shorelines act as a more natural buffer that absorb the wave energy, thus minimizing shoreline erosion and protecting the marsh.
How Are They Built
Federation's oyster bag sill at Jones Island.
Various techniques are used. They range from construction setbacks and simple plantings of marsh grass to more complex approaches that use bags of oyster shells, rock or wood or other structures to dampen wave energy. No two shorelines are the same, and living-shoreline strategies must be selected based on existing land uses, the amount of wave energy at the site and other local conditions.
Benefits of Living Shorelines
- Creates a natural buffer that absorbs wave energy and reduces erosion
- Maintains natural shoreline dynamics
- Very adaptable and may used in a wide range of habitats
- Can be less expensive than structures such as bulkheads and seawalls
- Preserves, creates or maintains habitat for plants and animals
- Restores critical feeding and nursery habitat for fish
- Traps, retains and treats runoff
- Provides aesthetic value, enhanced views, a sense of place and privacy to the property owner.
To demonstrate the effectiveness of living shorelines, the federation in 1999 began a pilot program to share the costs of such projects along the state’s estuaries. Through grant support from sources such as NOAA's Community-based Restoration Program, Restore America's Estuaries, the N.C. Clean Water Management Trust Fund and others, the federation has participated in the completion of over 30 living shoreline projects and provided technical support to numerous property owners and public partners throughout the estuarine region.
Rock serves as a sill at a living shoreline at the N.C. Aquarium
According to a N.C. Division of Coastal Management study that assessed 27 living shorelines in North Carolina, the projects provided effective erosion control, weren't navigation hazards, prevented erosion, didn't adversely affect water quality and often attracted oysters.
Changes Needed in State and Federal Permit Programs
State environmental agencies made significant progress in 2012 to remove regulatory hurdles to promote the widespread use of living shorelines, however, much more needs to be done to effect real change. Currently, the NC Division of Coastal Management
authorizes bulkheads and revetments in a few days, and requires no formal application process. At the same time, the application process for sills and other living shoreline methods requires a detailed application and plan review process, and can take 3-6 months for typical projects.
In addition, the Wilmington District of the U.S. Army Corps of Engineers
(COE) authorizes bulkheads and revetments with no review through an automatic general permit, but an individual permit is required for living shoreline projects, costing thousands of dollars for property owners and months of preparation and review time. A Federation study
of federal permit approaches within 10 COE districts found that 9 districts authorized all shoreline stabilization structures with the same permit type, and many of the districts have adopted incorporated regulatory language or adopted new permits to promote the use of living shoreline projects, and discourage the use of bulkheads and revetments. Ironically, the study found that only the Wilmington District COE creates a regulatory incentive for hardened approaches, and significant regulatory hurdles for applicants seeking to use more natural approaches that provide erosion control and protect critical habitats.
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