Coastal Storms Causing Major Erosion
HARWICH – The south coastline from Red River Beach to the Herring River has been pummeled by storm surges driven by three major coastal storms over the past month, causing major erosion and property damage, according to Conservation Administrator Amy Usowski.
“Wintertime is when we see the most erosion on the Cape,” she said. “Usually on the Nantucket Sound side we’re a lot more lucky, but we’ve had three storms in a month out of the south and southeast which have been extreme for us. We’re seeing more inundation.”
There was major flooding in Saquatucket, Wychmere and Allen harbors during the storms, said Harbormaster John Rendon. The Saquatucket Harbor marina access road was completely under water; in his more than a decade of working here he said he remembers very few times when that road was flooded.
“Twice in one week is alarming,” Rendon said.
Two major storms that hit only a few days apart two weeks ago included major storm surges. Usowski said the first one on Wednesday, Jan. 10 had a six-foot surge, causing serious erosion and significant flooding. The storm on Saturday, Jan. 13 came on an astronomical high tide and persisted for a much longer duration. It also battered the coastline, causing major flooding.
Sections of the shoreline have been hit hard, according to Usowski, especially along Shore Road in West Harwich, where properties which have no coastal protection have experienced 10 to 15 feet of erosion. Seawalls and revetments have been damaged, she added.
“It’s an El Nino year bringing more active weather patterns to the Northeast,” she said, “and everything is more extreme with climate change and sea level rise. Rains are torrential and can flood our roads, structures, and infrastructures not designed for a couple of inches of rain an hour.”
The coastal storms come with winds greater than 50 miles per hour out of the south and southeast. Usowski said the Shore Road coastline faces directly south to southeast and is taking the surges head-on.
She said she has had many calls from property owners seeking information on how to address erosion issues and damaged seawalls. One bulkhead along the shoreline was pulled apart, she said. The town had damage to every one of its beach access stairs, and there is a lot of materials that will have to be cleaned up along the shoreline.
Usowski is spending much of her time meeting with property owners, looking at their beaches and educating people on the steps that are necessary to address conditions caused by the storms, including filing a notice of intent with the conservation commission for work that will occur along the shore.
There are steps that can be taken to protect waterfront properties, she said. With proper permitting, hard solutions like rock revetments can be put in place along coastal banks, and soft solutions such fiber rolls can be used to protect the toe of a bank. But bulkheads are not allowed, she added, and structures are not allowed on lower-lying coastal dunes.
Revetments carry their own problems. When coastal banks are armored, Usowski said, the structures do not allow sand from the coastal bank to slide down and nourish the beach below, which causes the beach elevation to become lower, allowing waves to crash closer to the seawalls with greater force.
“In general, we are seeing more extreme and higher high tides and lower tides in the intertidal zone are getting smaller,” she said. “At Red River Beach it doesn’t take you as long to get out to deeper water to swim anymore.”
At Red River Beach, water topped over the bulkhead at the parking lot and the beach lost a lot of sand, which will be replaced with dredge material, Usowski said.
At the culvert beneath Uncle Venies Road just before the entrance to the parking lot, some of the rocks were pulled into the stream, disrupting the water flow. At the breakwater on the east end of the beach, rocks were nearly separated, making conditions there much more vulnerable, she said.
The town has a Chapter 91 permit that allows for the beaches to be nourished using dredged materials. Those materials get placed on public beaches. When there is excess sand, the town allows private beachfront property owners to bid on volumes of sand by the cubic yard to nourish private beaches. Beachfront property owners should be nourishing their beaches, she said.
“People are going to be screaming for beach sand this year,” Rendon said.
When the Saquatucket Harbor marina was reconstructed in 2018, the bulkhead along the lower road in the harbor was not rebuilt. Engineers said that the bulkhead would be fine for another decade, Rendon said.
The town’s capital plan includes design plans for a new bulkhead in fiscal 2026 and construction in two years later. With water coming over the top of the bulkhead in the recent storms, raising the height of that bulkhead will be an element of the design for the new structure, he said.
Wychmere Harbor pier, which was raised when it was reconstructed in 2014-2015, was underwater during the storms, along with lower portions of the town’s shellfish laboratory. The newly resurfaced parking lot at Allen Harbor was three-quarters under water, said Rendon.
“But there was no damage from these tides to the floats and ramps,” he added.
Usowski said the state Department of Environmental Protection is working on new Chapter 91 regulations to address climate change resiliency.
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