In 2011, after years of debate, North Carolina lawmakers opened the coast to a maximum of four new terminal groins to control beach erosion at inlets. A year later, at least that many beach communities in the state’s southeast have laid the groundwork to build them. Tuesday at the annual conference of the N.C. Beach, Inlet and Waterway Association (NCBIWA), the effort at Holden Beach received a spotlight and support from officials who claimed the structures shouldn’t be as controversial as they are.
The groin planned for the eroded east end of Holden Beach may be the conservator of the town’s economy, planners suggested. For a bad-case scenario, if 50 percent of the beach eroded away the loss would be $14 million in sales and other business activity, according to a presentation Tuesday from Fran Way, a coastal engineer with Applied Technology & Management, which is helping to plan the proposed Holden Beach terminal groin.
“These numbers are primarily what’s driving the local economy,” Way told conference attendees at Wrightsville Beach’s Blockade Runner hotel. The gathering covered a range of local, state and national coast-related topics Monday and Tuesday.
For more economic perspective, Way on Tuesday also cited a state-ordered report that coastal engineering firm Moffatt & Nichol produced in 2010 on the feasibility of terminal groins. It determined more than $27 million in property is at risk on Holden Beach west of Lockwood Folly Inlet. On the east side of the inlet is Oak Island, where nearly $110 million in nearby property may be in harm’s way.
A terminal groin, usually built of mounded rock, acts like an arm reaching from the end of an island to hold beach sand in place, essentially for the protection of nearby property. Per the legislation that legalized the structures—Senate Bill 110, Session Law 2011-387—the building of any terminal groin in North Carolina would have to coincide with a sand placement project, and the groin would serve to keep that new sand stable.
Holden Beach plans to build its groin at the east end of the island, which has seen high erosion rates. (The west end of the island is actually accreting.) Way noted Tuesday the east end is currently somewhat stable, but past hurricanes have shown how quickly that can change. In his presentation he displayed a big-screen image of damage following 2008’s Tropical Storm Hannah, which ate parts of Holden Beach up to the road.
Since 2001 the town’s beach strand has received four renourishments ranging from 140,000-201,000 cubic yards of sand placed in a program that Town Manager David Hewett thinks will benefit from the installation of a terminal groin. Ideally, the groin in its sand-retention function would reduce the erosion rate on the east end and make for less frequent need for beach nourishment, which can cost millions of dollars.
“Subjectively, there’s the belief that it will complement the existing program,” Hewett said of the pursued groin. Construction costs would vary based on the design and materials used. The Moffat & Nichol report stated groin projects—including permitting, design and the sand placement component—can range from $3.45 million to $10.85 million.
But the town is currently threading through a required environmental impact statement—a two-year process roughly 10 months in at this point—that should address whether a terminal structure is at all appropriate for Holden Beach and the surrounding area.
Opponents of terminal groins believe the structures will have detrimental impacts on downdrift shorelines by reducing the amount of sand that would naturally flow to them. The N.C. Coastal Federation for one lobbied hard to prevent their legalization last year in North Carolina, limited as it was. That group also predicted the amended ban was the first step in a complete undoing of the state’s longstanding ban on hardened coastal structures like seawalls and navigational jetties. The federaton prefers a natural coastline.
The only other state with such a prohibition is Oregon.
But officials at Tuesday’s conference said groins properly designed should bear no adverse impacts to neighbors. “They’re low-profile, they’ll be leaky, they’ll allow downdrift sand to bypass,” Way said.
If a downdrift shoreline does end up starving of sand, then the groin’s permit holder could arrange for a sand placement, he added. Other options are modifying the groin to retain less sand. Ultimately, a groin could be dismantled.
To offer full contrast, Holden Beach’s work plan discusses what the town may expect if it abandons coastal management altogether: “Properties would likely be condemned and require removal where homes and infrastructure are impacted. This would result in tax revenue losses accumulated to Brunswick County and the Town of Holden Beach in addition to the substantial loss of property value to the individual property owners.
“The no-action alternative,” it adds, “would also likely limit beach recreation and tourism due to reduced access and minimal available dry beach at higher tides.”
The town’s resolution to apply for a groin came in September 2011. The subsequent work plan estimated construction in the winter of 2013-2014. The costs would be covered by the Town of Holden Beach (the legislation concerning terminal groins forbids state dollars from such projects).
Absent the option of terminal groin construction, developed beaches generally have to rely on recurring renourishments, temporary sandbags and, if it comes to it, property relocation.
The groin “is another mechanism by which we can manage the strand,” said Hewett.
Ocean Isle Beach, Bald Head Island and Figure Eight Island are also actively pursuing the structures.
Contact Ben Brown at email@example.com or (910) 772-6335. On Twitter: @benbrownmedia