PINE KNOLL SHORES — Bogue Banks beaches lost about 3.6 million cubic yards of sand during Hurricane Florence in September 2018 and continued to lose more after the storm, up through the spring of this year.
The continued loss was surprising and bad news Monday afternoon when Nicole VanderBeke of Moffitt & Nichol, the county’s beach engineering firm, gave the company’s annual “State of the Beach” report to the Carteret County Beach Commission during its meeting in Pine Knoll Shores Town Hall.
Still worse, Ms. VanderBeke said to the commission, which advises the County Shore Protection Office, most of the lost sand is “piled offshore,” much of it at depths of 20 to 30 feet below sea level “and won’t come back.”
It didn’t come back during the summer months, when prevailing southwest winds usually add sand to the beach, she said, and it’s highly unlikely anything else will provide the necessary movement.
Geodynamics of Newport, the county’s beach surveying firm, performed its pre-hurricane season survey for Moffatt & Nichol in the spring. Prior to that, it had performed a survey days after Florence, and that’s how Moffatt & Nichol accounted for sand loss.
Ms. VanderBeke attributed the post-Florence sand loss mostly to several unnamed storm events that generated ocean waves of greater than 14 feet.
“We had a nice recovery from (normal erosion) over the summer (of 2018),” she said. “Then Florence, then these other events.”
Greg Rudolph, manager of the shore protection office, agreed with Ms. VanderBeke that the lost sand won’t come back.
“It went way out there and it’s staying way out there,” he said during the meeting Monday.
As a result, while beaches might look good to the naked eye – especially in eastern Emerald Isle, Indian Beach and Salter Path, where a nourishment project was completed this spring – it’s somewhat deceiving, Mr. Rudolph said.
“We’re fortunate to have had this project to replenish what was lost in Florence,” as well as another project to do the same on the rest of the island early next year, Ms. VanderBeke added Monday, and planners are hoping it will make up for some of the sand lost since Florence, too.
The annual survey, as well as post-storm surveys, divides Bogue Banks into 122 transects, and sand volume is measured in the water, out to -30 feet, and on land, with a boat and an ATV, respectively. The key depth in the water is -12 feet, because that is where sand provides some protection, as does the sand on land, from storm surge during hurricanes.
Sand at the -12-foot depth is also more likely to be moved ashore by normal summertime conditions than sand farther offshore.
The surveys are used to help the county determine when nourishment projects are needed, but are also essential in quantifying losses so the county can apply for lost-sand reimbursement money from the Federal Emergency Management Agency after storms.
Just this month, for example, FEMA announced reimbursements totaling about $18 million for sand lost to Florence in Pine Knoll Shores and Indian Beach. Officials are hoping for even more money for sand lost in Emerald Isle.
In her written report to the shore protection office and the beach commission, Ms. VanderBeke called the past year “an anomaly,” because there was a hurricane and a nourishment project.
It’s hard to know exactly what caused the post-Florence sand losses.
It is, Ms. VanderBeke wrote in her report, “cost-prohibitive to survey subsequent to each and every individual ‘small-scale’ event, such as after a coastal low (pressure system) or distant tropical storm passes.”
What the losses demonstrate is the importance of the county’s ongoing beach nourishment program, she said Monday.
Since the program began in 1999, after Hurricane Floyd the previous year, she wrote in her report, “Bogue Banks has gained roughly 6 million cubic yards of sand … mostly attributed to the many beach nourishment projects that have been constructed along the island beginning in 2001.
“A total of approximately 15.5 million cubic yards of sand have been placed directly on Bogue Banks as a result of beach nourishment, meaning 9.5 million cubic yards have since eroded off the beach.
“If we average the volume loss (-9.5 million cubic yards) across the entire 128,393 feet (24.3 miles) of Bogue Banks oceanfront,” the written report continues, “the island has lost sand at a rate of 3.9 cubic yards per linear foot (per year) since 1999.”
But the average loss before this year was only 2 cubic yards per linear foot, which “again demonstrates the type of impact Florence had along Bogue Banks.”
In her talk Monday, Ms. VanderBeke said Moffatt and Nichol is already looking at another nourishment project for 2021, one Mr. Rudolph said would likely focus on central Emerald Isle.
The survey also looks at Bear Island – in Hammocks Beach State Park, in Onslow County across Bogue Inlet from Emerald Isle – as well as Shackleford Banks.
Ms. VanderBeke told the commission Monday major losses continue to occur at the west end of Shackleford Banks, to the point where two of the original transects the survey started with years ago are now completely under water. However, she said most of the rest of Shackleford Banks, at the time of survey, seems to have been relatively stable.
Bear Island experienced major erosion, basically along its entire length, from Florence.
As for Bogue Inlet, the major passageway from the Intracoastal Waterway to the ocean for boaters in the western end of Carteret County, Ms. VanderBeke said it was relatively stable this year.
Emerald Isle in 2005 paid millions, as did the state, to relocate the channel farther west to reduce or stop erosion of the beach at “The Point,” an area of recreational value and the site of many expensive homes that are important to the town’s tax base.
The inlet channel has been migrating east toward Emerald Isle since then, but Ms. VanderBeke told the commission the migration slowed greatly the past few years and was almost nonexistent in the past year.
Emerald Isle officials have long expected to have to pay to move the channel again, but that doesn’t seem imminent right now.
Contact Brad Rich at 252-864-1532; email Brad@thenewstimes.com; or follow on Twitter @brichccnt.