Shift to living shorelines preserves precious coast
The natural beauty of the Southeast coast continues to draw tourists and transplants in ever-growing numbers. Once on the coast, they soon realize they’re in the middle of an age-old dialogue between land and water as the tide ebbs and flows in an ever-shifting dance.
For decades, the most common response to this back-and-forth, which often manifests as frequent flooding and erosion, was to stabilize shorelines by building traditional hardened structures like bulkheads or seawalls. But, in recent years, living shorelines have come to the fore as a cost-effective, durable, and ecologically superior alternative.
Living shorelines use effective placement of mostly native materials to absorb incoming waves and mitigate erosion while creating attractive places where the natural world thrives. This often involves using native wetlands plants at strategic points along the shoreline, or even oyster beds, to break up wave energy and reduce erosion. Among their numerous benefits, living shorelines:
- serve as nursery grounds for fish and shellfish;
- provide feeding areas for shorebirds and wading birds;
- allow shoreline ecosystems to migrate as water levels change;
- improve water quality by capturing the sediment washing off the land; and
- support the growth of marsh grasses that filter runoff and provide safe havens for wildlife.
Living shorelines also cost less when compared to hardened structures. Once established, they become self-sustaining without the maintenance and replacement costs of other traditional hard structures. More resilient than bulkheads and the like, living shorelines better withstand storm surges, and the subsequent receding waters. Living shorelines are also cost-effective when the long-term maintenance and replacement costs of traditional armoring are factored in.
Seawalls cause shore erosion
Watch how wave energy hits seawalls and then starts to undercut the structure, undoing the very stabilization they’re meant to ensure.
Consider Alabama’s Mobile Bay, where by 1997 more than one-third of the shoreline had been armored. As the country’s population grows, development pressure along the coast is building. With more development and rising sea levels comes the demand for more hardened shorelines.
Reading the writing on the (sea)wall, the U.S. Army Corps of Engineers district overseeing Mobile Bay (as well as the rest of Alabama) initiated a program, much like what Virginia and Maryland have done in the Chesapeake Bay, that prioritizes living shorelines in the permitting process. In both regions, property owners must demonstrate that a living shoreline won’t work in a particular location before the Corps will consider permitting construction of a hard structure like a bulkhead. This approach has led to a surge in living shorelines construction.
The Corps recently updated the single general permit used nationwide for waterfront stabilizations systems. During review of the draft permit over the last several months, SELC and our partners have advocated strongly for a shift in the permit design to increase prioritization of living shorelines.
At the same time, SELC is tackling the lack of technical experience that is hampering implementation of living shorelines. A new technical guide for contractors and a schedule of regional workshops look to provide builders with the tools they need to properly build these natural barriers.
Living shorelines are superior alternatives to traditional erosion controls. Continued implementation of these systems will help maintain the health of wetland and aquatic environments vital to the Southeast’s seafood production, recreation, and the region’s incomparable biological diversity.