Beach Stabilization and Artificial Reefs


For over 35 years I have observed changes to this paradise we call the Outer Banks. Some changes come with the inevitable growth of any area. Other changes come from the effects of mother nature, such as beach erosion. Problems arise when these changes impact on each other. Over the years we have seen many older homes consumed by the storm surge and retreating shoreline. Hopefully the planned Beach Nourishment program will help control this severe erosion in certain areas.

As a Geologist and avid SCUBA diver I have also studied and observed the occurrence of shipwrecks and their effects on the environment. It has been long documented that shipwrecks can provide a wonderful habitat for a diversity of marine creatures to thrive on. This is especially true on our coast because we have no rocky bottom or natural reefs that can provide a haven for creatures to hide in, nest on or attach themselves to, since there is only shifting sand. The shipwrecks can provide such a diverse and growing environment for the natural occurring marine life, both plant and animals, that the State of North Carolina along with many other states, have purposely sunk many old vessels and other structures to study and aid in this. It has proven that not only can they provide a safe haven for the different species to grow and flourish, but it also provides economic possibilities for fishermen, divers, residents and visitors. Most of these artificial reefs have been sunk well offshore in deeper water. However, observing near shore natural ship wrecks such as the 71 years old "Triangle Wrecks" 200 yards off the beach and the recently re-exposed 75 year old schooner wreck the Irma in the surf zone off Kill Devil Hills, wrecks pretty much stay where they sank and stabilize or buildup the sand around them.

This brings us to another possibility for the use of old vessels as artificial reefs. Sunk in the near shore environment, below mean low water depth parallel to the shoreline, they also can provide a breakwater barrier for storm driven waves that would otherwise impact the shore full force. The first two processes produce the normal transportation of sand to and from the beach. The third process is the one that controls whether there is a netWave and current processes that effect sediment transport and erosion of the beaches are centered on three main points: (1) waves are transformed as they approach the shore and produce sediment transport; (2) waves generate nearshore currents which also produce sediment transport; and (3) temporal fluctuations in wave regime occur from alterations between fairweather and storm conditions. deposition of sand or a net erosion of sand during storms. It is to this last condition of severe loss of sand causing a retreating shoreline that concerns all of us.

The beach nourishment program will help replace and build up the net losses of sand that are eroded away. In addition to this process a program of nearshore artificial reefs placed in the most impacted areas could help stabilize these replenished areas. Placed so that the uppermost structure is at a certain depth below mean low water level, normal fluctuations of tides, waves and currents are impacted very little, in periods of increased storm wave intensity the larger waves are caused to break earlier. This breakwater reduces the waves striking the shore behind it and reduces its capacity to remove material. Not only does this stabilize the foreshore and backshore areas but can also promote buildup in this shore environment and promote an increase in marine habitat and growth. This can be a positive approach for all inhabitants and visitors to the Outer Banks.

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