On a misty, windy morning in April 2007 Chris Kennedy, Martha’s Vineyard superintendent for The Trustees of Reservations, had just returned from the part of South Beach in Edgartown known as Norton Point.
The night before Katama Bay had filled to overflowing by the flood of an astronomical high tide, topped off by the overwash and storm surge of a Patriots’ Day gale. On the south side of Norton Point relentless, reaching ocean waves had flattened, narrowed and weakened the barrier beach. With the fall of the tide on the ocean side shortly after midnight, the beach had broken open to the Atlantic. Water in the bay had rushed out to the ocean, severing Chappaquiddick from the rest of the Vineyard for the first time in 30 years but restoring the word “island” to its name as well as its spirit.
The channel through the beach was only a few hours old, but it was already more than 200 feet wide. “This clearly is a major breach,” Mr. Kennedy told the Gazette that Tuesday morning, April 17, 2007. “It’s really something to see, just the sheer volume of water rushing through there. I don’t think this thing is going to heal over in the short term.”
He also said: “This is not a catastrophe. It is simply Mother Nature at work.”
The Schifter family — whose tall, gabled home began its foot-by-foot move back from the slumping bluffs of Wasque Point on Chappaquiddick this weekend — might dispute that idea, since the opening through Norton Point and the beyond-belief erosion of beach and land in front of their home in the last two years are directly related.
Two weeks ago, W. Sterling Wall, a coastal geologist working with the family on the problems caused by the erosion of today, told a conference of scientists and audience members at the Harbor View Hotel in Edgartown that when the Schifters went through the permitting process in 2003 and 2004 before starting construction of the new home later that year, severe erosion was on everyone’s mind.
“We looked at historical information,” Mr. Wall said. “We knew there was a barrier beach here . . . [and] we knew that it was dynamic.”
But if town officials and coastal geologists were looking at the changeability of the beach that faced the ocean at Wasque Point — caused by sea level rise, storms, seasonal changes and the periodic openings of Norton Point Beach — they may have overlooked the future vulnerability of the ocean-facing embankment behind it: the one on which the Schifter house would rise. Studies of this phenomenon go back to the 1870s.
The previous long-term opening through Norton Point began with a storm in the winter of 1953 and closed at Wasque Point in late 1969 or early 1970.
And scientific papers, nautical charts and scores of stories in the Vineyard Gazette dating back decades reveal that some years after an opening through Norton Point, the bluffs along the southern shoreline of Chappaquiddick — and especially at Wasque Point — begin to erode at remarkable and irretrievable rates.
“Cliff retreat at Wasque Point is documented from aerial photographs and field observations and shows a total loss of more than 213 m. [700 feet] in the period 1948-1969,” wrote J. Gordon (Pete) Ogden 3rd, a botanist and geologist, in a report published in Quaternary Research 4 in 1974. Those years encompassed two successive openings through Norton Point.
“The average rate of 10 [metres per year] for this 21-year period,” Mr. Ogden wrote, “must rank as one of the most vigorous rates of coastal erosion anywhere the sea is attacking a headland of more than 10 [metres] elevation.” Memories of the rapid retreat of this embankment, as well as the loss of land and trees and shrubbery to the sea, remain with anyone who swam near Wasque, fished from it or just visited it in the 1960s.
From reports, maps and newspaper stories, it was also clear that Norton Point had opened to the Atlantic several times in the previous 150 years, followed by the same patterns of erosion. Accounts in the Gazette going back to the middle of the 19th century show that natural openings occurred in 1886, 1953, and 1976. The town dug artificial openings in 1921 and 1937 to help flush the shellfish beds of Katama Bay with fresh seawater and offer quicker boating access from Edgartown to the Atlantic Ocean.
Most of these openings, natural and manmade, lasted roughly 17 years. (Nautical charts and anecdotal evidence suggest an inlet that closed in 1869 may have been opened for many decades longer than that.) According to the Gazette and studies going back to the 1870s, most of these openings behaved in remarkably similar ways: A storm opens the beach and the inlet begins to migrate eastward with the longshore current toward Chappaquiddick. Once it reaches Chappy, tides and currents move the beach of Norton Point offshore, creating a tidal channel between the beach and Chappy as the point continues to grow to the east. The opening finally encounters new tidal forces at Wasque Point where, over time, it closes.
But as the opening approaches Chappaquiddick, history and contemporary experience show, the inlet prevents “sediment transport” — migrating sand — from reaching the beach along the southern Chappy shoreline. The beach wastes away, allowing the Atlantic to attack the bluffs directly for years at a time, causing the terrific erosion Mr. Ogden wrote about in 1974.
Others wrote of it long before him. In 1886, Henry L. Whiting, a West Tisbury resident who would become chief of the U.S. Coast and Geodetic Survey, authored a paper on erosion around the Island. Summarizing his study of the coastline, he noted that the highlands of Wasque Point had eroded more than any other landscape on the Vineyard — more than 500 feet over 40 years.
These studies mostly leave out descriptions of the nearly tectonic falling away of the embankment that Islanders have witnessed in the last two years, as the present-day opening through Norton Point approached Chappy in late 2011 and began to rob the coastline of sand and beach, thereby exposing the bluffs behind it to unbroken assault by the sea.
Every day since then, the ocean has excavated the base of the bluffs to some degree, greater during storms and less during calm days. This has caused the bluffs to slump and cave into the ocean in startling ways.
From the top of the embankments, live scrub oaks fall by the score into the swash 30 feet below. Others hang over the edge, days or even just hours from death, their roots dangling like severed arteries and veins. Walking trails break off over the water as if sliced away by a great hatchet. Seas chew up parking lots, cut off dirt and sandy roads and overrun lowlands, blackening bayberry bushes. People who view the ravaging of the south shore of Chappaquiddick one week have returned the next to find lengths of it missing and unrecognizable.
In the second half of 2011, as Norton Point approached, the Chappy shoreline began to lose the Atlantic-facing beach in front of it, as well as a pond between the beach and the bluffs and an acre and a half of land on which the Schifter house rests. In the last 18 months it became clear that the home and outbuildings faced total destruction.
“We had lost at least 200 to 400 feet of beach and dune, as well as Swan Pond, and by the early portion of 2012 we were then removing something on the order of 80 feet of the coastal bank,” Mr. Wall told the conference on June 20 this year. “At that point they had lost at least 590 feet of beach, dune and bank in early 2012. That was all due to the 2007 . . . Patriots’ Day northeaster [and opening], which had left us with this condition.”
Then things got worse. Though coastal engineers had devised and built a temporary terraced embankment in front of the bluffs to buy time while the town reviewed an emergency application to move the house and other buildings back from the collapsing bluffs, the storms of this winter robbed the embankment of even more earth.
“We had some extraordinary rates of erosion to deal with,” Mr. Wall said. “We were looking at a foot a day. In late September and October, it had diminished a little bit. And, whoops, here came Hurricane Sandy [on Oct. 29], where we lost 20 to 40 feet over the storm, at least 20 feet in one day. We had a reduction in the rate in November through January, even though we had frequent storms. Nemo took another 11 to 14 feet over two days [Feb. 8-9].”
When built in 2007, the Schifter home stood about 280 feet back from the edge of the embankment, Mr. Wall said. When the last northeaster finished with the bluffs on March 7, the home stood from 40 to as little as 25 feet back.
Another speaker at the conference — Peter Rosen, a professor in the department of marine and environmental sciences at Northeastern University who is also working with the Schifters — said that what had surprised him and his colleagues was the fact that the Norton Point opening did not behave the way other coastal inlets do along the New England coastline and beyond.
The tide running in and out through the regular entrance to Edgartown harbor helps to keep migrating Norton Point from joining Chappaquiddick at the earliest opportunity, several scientists at the Woods Hole Oceanographic Institution believe. Instead, the contrary tides in the harbor and at the opening help to keep Norton Point moving along offshore of Chappaquiddick until it reaches distant Wasque Point, adding to the exposure and erosion of the Chappy shoreline.
David R. Foster — an ecologist, director of the Harvard Forest ecological laboratory in Petersham and a speaker at the Norton Point conference — said that the processes and consequences of an opening through Norton Point have long been known. Henry Mitchell, a scientist, and others had outlined them in papers dating back 130 years, he said.
“And so rather than being surprised, in fact,” Mr. Foster said, “a well established set of papers by people in the National Academy of Sciences laid out exactly what you’re describing. So it really shouldn’t be a surprise. It’s a system that’s different, but very well understood.”
Dr. Rosen questioned whether the dynamics of Norton Point were in fact well understood, but he made clear that he and other experts working with the Schifters had been caught off guard by it.
“It’s consistent in its repetitional pattern,” Dr. Rosen replied. “But walking into a system and not having time to research and trying to come up with answers, we’re piecing this together, and we have a lot of information today that we didn’t when we walked in on this, a moving shoreline.”
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