Hunting Island beach renourishment: Time is of essence
Many Beaufort residents are aware of the beach renourishment campaign for Hunting Island State Park that has been underway this spring.
Beach renourishment involves pumping sand from the ocean bed onto the beach, then using bulldozers to spread it and level it off. Many checks are in place when renourishment occurs, including sand sampling, as much sea and land creature protection as possible, and environmental impact studies. It is a complex issue that requires sensitivity to the environmental, social, and financial aspects of the projects; yet it remains largely unpredictable.
Some additional background may be helpful.
In 2005, the U.S. Geologic Survey issued its National Assessment of Shoreline Change for the Southeast Atlantic Coast. This study stated that the highest erosion rates in the Southeast were in South Carolina, and it confirmed what most Beaufort County residents already knew — the highest long-term rate of erosion in South Carolina is at the northeast end of Hunting Island, with erosion of up to 18.8 meters per year. Average annual erosion on the Atlantic Coast is 0.6 to 1.0 meter per year.
This same study also indicated that erosion decreases with renourishment and that renourishment is common in all Southeast Atlantic states except Georgia. Engineered structures such as revetments, groins, bulkheads, and seawalls are seen on 6 percent of the North Carolina coast, 27 percent of the South Carolina coast, 50 percent of the Georgia coast, and 45 percent of the east coast of Florida.
An article in the Journal of Coastal Research titled “The Physical Condition of South Carolina Beaches 1980-2010” concluded that while 80 percent of developed beaches were healthier in 2010 than 1980, undeveloped beaches exhibited high erosion, limited new sand input, and accelerated recession. About 75 percent of the undeveloped beaches in 2010 had moved much farther inland since 1980.
Between 1980 and 2010, 39.4 million cubic yards of sand was added to S.C. beaches through beach renourishment, principally to developed beaches. Both Hunting Island and Fripp Island are classified as minimally developed; Bay Point, Capers, and Pritchards Islands are undeveloped; and Hilton Head and Harbor Islands are nearing low-density development capacity.
Erosion of barrier islands is exacerbated by climate change that includes rising sea levels, increasing force of storms, and rising water temperatures. These dynamic systems are not easily controlled or predicted by humans, even though humans have placed the majority of pressure on these systems. When we attempt to remediate one problem in one place, those alterations will almost always have unintended consequences in other places.
Harbor Island residents have stated that the beach renourishment at Hunting Island in 2005-07 has increased Harbor Island’s erosion. For 150 years, Harbor Island benefited from Hunting Island’s rapid loss of sand from the northeast end. With the installation of groins on Hunting Island and 750,000 cubic yards of sand, erosion problems began to appear on Harbor Island — sand began to accumulate in Johnson’s Creek Inlet instead of on Harbor Island, probably because of the groin placement. Therefore, Harbor Island’s historic receipt of sand has now become a deficit of sand. In the case of Harbor Island, many houses are threatened.
Hunting Island’s famous cabins are all but gone, so the population most affected by loss of beach on Hunting Island is its 1 million visitors a year. The loss of the cabins on Hunting Island is witness to the hazards of building permanent structures on a non-permanent barrier island. Most people who can afford to build on a barrier island usually have the financial wherewithal to protect their investment. Few of Hunting Island’s visitors live on barrier islands.
Although members of Friends of Hunting Island have worked tirelessly to encourage the undertaking of the renourishment project this year, how and whether it proceeds is up to the legislators.
Friends of Hunting Island supports renourishment as a way to protect the lighthouse, preserve the beach, and keep Hunting Island a primary tourist destination in the Southeastern U.S. State parks representatives have assured the public that what is done at Hunting Island will be as responsible and careful as possible. Everyone involved is open to discussions and suggestions. But time is of the essence.
Nov. 28, 2015 When "Little Blue," one of Hunting Island's last cottages, disappears, it will also mark the end of an era for Beaufort County. | READ
This story was originally published June 1, 2016 at 11:46 AM with the headline "Hunting Island beach renourishment: Time is of essence."