Data Shows Increased Erosion In Seashore

EASTHAM – A lot can happen in 14 months.

It’s been that long since the Cape Cod National Seashore advisory commission last met, but erosion escalated significantly in some parts of the seashore since. 

That was the report given during the advisory commission’s Nov. 2 meeting, its first since the fall of last year. Scott Rasmussen, a GIS specialist with the seashore’s natural resource management and science division, updated the commission on the impacts of erosion at a number of areas within the seashore’s boundaries. 

Most alarmingly, he said, Coast Guard Beach in Eastham lost 26 feet of beach in just one month from January to February of this year.

“Storms drive coastal change,” Rasmussen said. “When you have a continuous surge for days on end, every high tide is just a killer. It just takes a little bit each time, sometimes a lot.”

Also in Eastham, the Bartlett property on Ocean View Drive has dwindled by 30 feet over the past two years, Rasmussen said. The Bartlett house, which dated back to the late 1600s, was demolished in February due to erosion to the bluff on which it sat.

More specifically, 26 feet of erosion occurred in the last year alone, said Rasmussen, who first started surveying the property in November 2023.

“Then as the months went by, I was noticing, ‘Man, this is eroding really, really fast,’” he said. Eventually, he said, he started surveying the property monthly until the house was demolished.

Marconi Beach in Wellfleet has seen between six and 16 feet of loss in the last three years. The Marconi station property, meanwhile, remains relatively stable, said Rasmussen, who reported a loss of only two and a half feet on the bluff. 

The bluff edge at Nauset Light in Eastham has seen between 12 and 22 feet of loss in the last three years, according to Rasmussen. Portions of the parking lot have been closed off due to erosion, he said.

Rasmussen said over the past 40 years, erosion within the seashore was occurring at an average clip of four feet a year. But some areas have been hit more severely than others. He showed areas that have been losing 12 to 13 feet of beach a year. 

“It’s a real eye opener,” he told the commission. “It’s something to take away when we look at these areas and say ‘10 years, how much time do I have?’ Well, this is what’s possible.”

Rasmussen said from “lighthouses to beach parking lots, the seashore has a history of relocating resources out of harm’s way.” Seashore Superintendent Jennifer Flynn on Monday said staff and the commission need to take a good look at the seashore’s existing resources, and how they can best be utilized and protected in the future.

“We talk often about adaptive retreat, but in some places we have no places to retreat,” she said. “We’re surrounded by private property, and it may be more than retreating. It may be envisioning what public use looks like in different areas.”

Flynn identified a number of properties within the seashore that are in substandard shape. Those include the mosquito control building at Hatches Harbor in Provincetown near the airport. The building, which dates back to 1910, is “beginning to fail,” she said. There are also issues at the Nauset Coast Guard station, including those related to bathrooms, trails and beach access at Coast Guard Beach.

“It’s very realistic that in 10 years, it’s going to have to look differently,” she said.

In terms of relocation, Flynn said that could include Nauset Light, which was last moved inland in 1996.

“We’re driven by what Mother Nature gives us,” she said.

Flynn said the seashore needs a five- to 10-year “runway” in its planning to allow for the permitting and funding that would be needed to address its infrastructure needs. 

“What we know is we are much better served if we don’t wait for it to be a crisis,” she told the commission. “These are all decisions that I think we all can see coming. They’re all going to be complicated, and all of them are going to be public.”