Natural Alternatives to Shoreline Erosion Protection
There are many types of waterfront property; some are nestled in quiet coves or small creeks, while others face open water and the waves that come with it. Some properties are suffering the effects of steady erosion, while others are stable or growing. For decades, despite the differences in shoreline types, there has mostly been a “one-size-fits-all” approach to shoreline protection – building bulkheads or installing rock or rip-rap revetments.
In recent years, we have learned much about the conditions that make a healthy river/Bay environment. Results of recent studies have shown that when compared to shorelines with vegetated marsh, hardened shorelines (bulkheads, rock revetments) have a lower abundance of bottom-dwelling organisms offshore and lower numbers of juvenile fish and crabs.
In many cases, where the waterfront is subject to waves of low to moderate energy, there are effective alternatives to shoreline hardening. These methods of shoreline protection are often referred to as “soft”, or “living” shoreline protection. Some of the benefits of this approach are
- Lower construction costs when compared to bulkheads and revetments
- Reduction of both sediment and pollutant flow into the creek or river
- Maintaining a link between aquatic and upland habitats.
- Creating a natural shoreline appearance.
- Restores or maintains critical spawning and nursery areas for fish, crabs and more.
In 2010, the Virginia Institute of Marine Sciences delivered a report to the Virginia General Assembly (.pdf download) on the value of living shorelines. This report resulted in a 2011 law that sets "living shorelines" as the preferred option for shoreline erosion control and sets up a general permit for living shorelines in Virgina.
Shorelines in creeks or coves that receive low energy waves can often be protected by methods other than building hard structures. Examples include (re)planting wetland vegetation and beach replenishment. These methods are appropriate if the property once had a vegetated wetland or beach, or if neighboring shorelines currently have vegetated wetland shorelines or beaches.
In marsh restoration projects, where no sand or sediment is added or removed, no regulatory permit may be needed, reducing both cost and time. However, you should always call your local wetlands board representative to be sure.
In locations with greater exposure to waves, it may still be possible to maintain a mostly natural shoreline. Three structural additions used for this purpose are near and offshore breakwaters, sills and low profile rock groins. Whereas the purpose of bulkheads and revetments is to reflect or absorb wave energy, sills, breakwaters and low rock groins are placed within the intertidal zone, or beyond the low tide mark to enhance sand buildup along the shoreline. In most cases, these structures are used in concert with beach replenishment and marsh plantings
Resources containing greater detail about Living Shorelines:
Native Plants and Wetland-Friendly Landscapes
Native plants are indigenous to an area. They have evolved and naturally adapted to the characteristics, like climate, soils and pests, of a certain region. Therefore, native plants are easier to grow and require minimal maintenance, reducing the need for watering and application of fertilizers and pesticides. The result is less pollutants that might be carried by runoff into our wetlands and rivers. A border of native plants can also act as a buffer to slow the flow of water from your yard (which reduces erosion) and provide a natural filter that can remove pollutants from runoff.
Using native plants in landscapes and buffer areas has an additional benefit. They provide wildlife with familiar sources of food, shelter and places to raise their young. This is important, as natural habitats are replaced by development. The Virginia Institute of Marine Sciences has a valuable resource page on native plants. The Chesapeake Bay Foundation has compiled a citizen's guide to backyard conservation, with resources. The Virginia Department of Conservation and Recreation offers a comprehensive description of buying, growing and the benefits of native plants. Additional resources include the Alliance for the Chesapeake Bay Bay Scapes program and the Chesapeake Conservation Landscaping Council.
As more people understand the benefits of using native plants, they have become more readily available in local nurseries and home stores. It’s important to purchase nursery-propagated plants, instead of those collected in the wild, to avoid depleting natural populations.
Other Landscaping Tips
- Allow native marsh grasses and wetland plants to grow between your lawn and the waterway. Do not mow marsh grass or cut down wetland shrubs, like salt bush.
Minimize the amount of paved surfaces in your yard to decrease runoff. Consider using mulch, stepping stones or bricks on sand for walkways or patios.
Enjoy a low-maintenance, low-cost yard by keeping grass lawns small and using no-maintenance ground covers where possible.
Use a mulching lawn mower that recycles lawn clippings, restores nutrients to the soil and reduces landfill waste.
Mow higher, no less than 3 inches, and less frequently.
Insist on a lawn care company that uses only organic fertilizers and natural pest management techniques.
Aerate lawn to decrease compaction and remove thatch.
When planning protection for your shoreline against erosion, consider natural methods like planting a fringe marsh, rather than “hardening” the shoreline, which may not be necessary. For more, check the Virginia Institute of Marine Science Living Shorelines resource page.
Consider a rain garden to slow and pool water so it soaks into the ground and filters runoff, instead of rushing into the wetland area in the back yard. Learn more from the Va. Department of Forestry rain gardens guide.
Install a rain barrel to capture roof runoff for reuse. See Alliance for the Chesapeake Bay's rain barrel planning and installation guide.
Avoid planting invasive plants. Learn which plants are invasive and how they impact your environment.