Friday, August 10, 2012

Conservation Tips: Living Shorelines


by Anna Salzburg, JRA Intern

Residents of the James River watershed and those visiting the James River typically do so because they want to reach the water, dip their toes in it, and see the wildlife embracing their natural habitat.  Unfortunately, artificial shoreline armor used to protect against shoreline degradation and stream bank destabilization resulting from ever-rising sea levels and increased stormwater flushes, prevents citizens from enjoying our water resources to their fullest.

What this conservation tip is really addressing is erosion and installing a “living shoreline” to resolve issues that result from erosion.  Open, linear shorelines receive the full impact of a wave, thereby increasing erosion.  A living shoreline incorporates an irregular shoreline design that causes waves to diverge, spread the energy out, and decrease erosion.  The Upper James River watershed experiences erosion, but with much smaller bank widths/depths and lower fetch factors (open water distance) that increase the potential for erosion.  Still, in these areas storm surges can overwhelm even the best management practices installed, resulting in pollution and erosion issues.  The living shoreline in the upper reaches of the James requires planting native species on an approximately 2:1 slope within the riparian buffer area to prevent land loss due to erosion.  JRA strongly recommends consulting with a professional in both streambank and shoreline restoration before conducting any activities in or near ANY body of water.  Even wetlands, streams, and creeks that appear dry most of the year are still regulated by the local, state, and federal agencies as jurisdictional areas. 

Jamestown 4-H Educational Center living shoreline project

A living shoreline results in many positive functions, which are similar to those of a wetland or any natural buffer abutting a water resource.  These positive functions include trapping sediment pollution, filtering pollution, providing habitat and food for wildlife, improving water quality, and decreasing the amount of nutrient pollution.  Materials used on a living shoreline include marsh plantings, shrubs, trees and a variety of structural and organic materials; including wetland plants, submerged aquatic vegetation (SAV), oyster reefs, and coir fiber logs.  Artificial shoreline armor products include riprap, bulkheads, and flood walls.  Unfortunately, artificial armor does nothing to increase the natural habitat and actually increases the rate of coastal erosion (NOAA). 

An example of a successful living shoreline project on the James River is the Jamestown 4-H Educational Center.  This project involved 400 feet of shoreline eroding at 18 inches a year.  A group of volunteers laid out the planting grid, drilled in the plant holes, fertilized the holes, and planted.  Stone sills are sometimes used at the base of a living shoreline to protect the plants, especially while they grow strong enough to withstand storm erosion.  A video of this project is located at http://www.youtube.com/watch?v=yyR249Af_FE  


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