Protecting Shorelines with Barrier Structures

Living Shoreline Solutions' WAD barriers being emplaced to protect a portion of Louisiana's offshore wetlands.

Living Shoreline Solutions’ WAD barriers being emplaced to protect a portion of Louisiana’s offshore wetlands.

A recent conference on protecting the world’s shorelines from hurricanes and other events exposed some proven solutions and new thoughts about using natural materials and man-made inert waste products to build protective offshore barriers. Reasons for holding the Conference on Ecological and Ecosystem Restoration (CEER 2014) in New Orleans was that the city is now protected by a new flood-protection barrier system, and the fact that Louisiana wetlands are still being lost at a rate of about a football-field an hour due to coastal erosion, rising sea levels, delta sediment starvation, subsidence and man-made causes. The complex interrelations presented by these problems  was fruitful ground for the 380 speakers and 100 poster presenters to discuss ways to preserve wetlands and shorelines.

Beach-front developers and homeowners who paid millions of dollars for their properties are vitally interested in helping to protect their resorts, condos and homes from loss of beach sands due to shore-line erosion. Very often this may require mining sand from some other location and periodically re-nourishing the beaches after major storms.  Properly designed protective barriers not only protect existing beaches from erosion, but also cause sand to naturally be deposited in the quieter waters behind the barriers and grow the beaches, provided that sand is naturally being transported along the beach, as is often the case along the eastern cost of the U.S.

In South Florida and other parts of the world, the preservation and reestablishment of coral reefs is a major issue. The growing acidification of the ocean’s waters has retarded the growth of natural coral. The emplacements of irregularly shaped structures by the Reef Ball Foundation not only provides hard structures for corals and other animals to colonize, but their Eternal Reef Memorials allows the lately departed to make a contribution to the environment by having their ashes incorporated into the structure (www.eternalreefs.com). At selected locations in the U.S. and elsewhere, the family attends when the memorial reef balls are cast and may put in the concrete any small items that were significant to the individual and inscribe or attach a memorial plaque.  In cases where the Foundation had already placed a ball-barrier structure in front of private homes, the memorial ball might also be included so that the dead remain close to the places and families that they loved.

Reef Ball on barge prior to emplacement.

Reef Ball on barge prior to emplacement.

The WAD triangular barriers and the Reef Balls are made of concrete and cast on-shore as near as possible to the locations where they will be placed. They are then taken out by local barge operators and placed off shore. Although heavy, both structures are hollow and ported to allow a maximum surface area to support natural growth. These synthetic structures are far superior to rubber tires, automobile bodies or decommissioned ships, because they do not leach toxic materials into the environment or degrade into plastic micro-beads.  This technology is now well established, and the companies that contract for the structures are well versed in obtaining the required permits as part of their contracts.

In third-world countries what cannot afford to import expensive rock or use concrete to make barriers, my poster, “The Billion Bottle Barrier,” described how local waste materials might be contained in bags or cages made of natural materials, say bamboo or hemp; and interconnected with  cables made of  animal hair or plant fibers to provide flexible barriers to help protect nearby shorelines. In the example shown by my poster, the bottles are filled with sand with a wad of paper placed in the neck as a stopper. These are placed in a flexible array off-shore and the lines of interconnected containers are secured by pilings driven into the substrate.   In addition, the poster proposed that research on materials and installation methods might be done by small groups of citizen scientists from around the world and that this world-crowd-sourced data be centrally collected and disseminated through periodic newsletters. I am now seeking a university, NGO or private company to take on this project to help protect the world’s endangered wetlands.  Many who saw the poster  said that this was an interesting concept that they thought had merit, but I have received no commitments to date. Because of the numerous permits that must be obtained from multiple Federal and State agencies in the U.S., it is impractical to do this wide-scope research in the U.S., because each use of new materials and each new site would require permitting, even for the emplacement of  small test structures in off-shore environments.

Reef Balls with shellfish.

Reef Balls with shellfish.

A coincidental, but not inconsequential, consequence of placing offshore structures is that shellfish, fish and natural vegetation is attracted to them. Depending on the environment and the purpose of the structure, the accumulated trapped sediment and overgrowth may form the core of a shoal or small island that may ultimately support  terrestrial vegetation to further reduce the impact of  high tides and storm-surge waves. These barriers can offer a significant protection to hard-built structures closer to shore that offer protection for cities like New Orleans.

Alabama and Mississippi now offer property owners incentives and tax breaks to place protective structures off their private holdings. Living Shoreline Solutions  and  the Reef Ball Foundation, who now have a decade of experience, are well versed in local laws and able to assist property owners in applying for these incentives in addition to designing strictures to meet the needs of  particular sites. In general, the WAD barriers are more effective if they are exposed at high tides, but the Reef Balls and other WAD designs can be installed so that they do not protrude above the water and spoil the ocean view from hotels and other on-shore properties.

I had the opportunity to do interviews with Scott Bartkowski  who founded Living Shorelines Solutions, Inc. and Jim McFarlane who represented the Reef Ball Foundation at the conference. These interviews may be seen in a few days as a YouTube video and links will be provided on this blog. McFarlane’s interview is now available at: http://youtu.be/YHTk_zPOr3g.  If you would like more information on their organizations you can go to http://www.LivingShorelineSolutions.com and http://www.reefball.com. To gain a more complete overview of the concept you can see the videos below.

From Living Shoreline Solutions:

From the Reef Ball Foundation:

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