Breach at Norton Point Beach Wreaks Havoc on Harbor Tides
By MARK ALAN LOVEWELL
Mariners beware. Tides and currents have changed dramatically in Edgartown harbor since the breach of Norton Point beach in April and the federal government has no plans to establish new tide or current tables soon. The power of the current in Edgartown Harbor is not only three times faster at Chappaquiddick Point, nobody yet knows with certainty when high or low tide takes place.
"The time of high water is nowhere near what the papers say. It is hours off," said Joe Cressy, chairman of the Edgartown marine advisory committee. "Now what happens is the flood tide comes in from the sea, [the direction of Norton Point Beach]; exactly the reverse of what used to happen."
On top of that, the high tide can come from either direction.
Jack Blake, who raises cultured oysters in Katama Bay, said: "We don't have any extreme low tides in Katama Bay anymore. I have seen the current go both directions when it is dropping."
Like many Edgartown shellfishermen, Mr. Blake had been wishing for the break for the past 25 years. "But now that it is open," he said, "it is a real pain in the neck."
However, he said, "the oysters love it. They are certainly saltier."
Harbor master Charles Blair sent out a mailing to mooring permit holders alerting them that this summer will be different in the harbor, and mariners need to use caution.
Roy Hayes, owner of the Chappaquiddick ferry, said yesterday his main concern is collisions. "If we have a collision, the Coast Guard is going to have us shut down," Mr. Hayes said. "I am very cautious about this summer."
Mr. Blake said those working on the waterfront are still trying to figure out a way to interpret the rising and falling tides and the changing currents.
"Old sand bars near the opening have changed. Some are building and some are losing sand. I had a 50-pound juvenile harbor seal on my nursery this week, and for this time of year that is unheard of," Mr. Blake said.
In Katama Bay, where most of his oysters grow, Mr. Blake feels more exposed to the influence of the open ocean, he said. Ocean waves now make their way into Katama Bay. "I can have waves coming from two different directions. You can get seasick down there."
Mr. Cressy, an avid boater, thinks he has figured out how to explain the change: "When the breach happened there was a war between Nantucket Sound and the Atlantic Ocean," he said, adding it took several days until there was any rational way to see what was happening.
Tides and currents in the Atlantic Ocean, south of the Vineyard, are different from the tides and currents working in Nantucket and Vineyard Sound. Sometimes there is movement in opposite directions, as evidenced in the Eldridge Tide and Pilot Book.
Mr. Cressy said Nantucket Sound and Vineyard Sound are inland seas, and they don't connect to the Atlantic Ocean - except where Vineyard Sound empties into Block Island Sound, and at Pollock Rip, and in Muskeget Channel that connects to the Atlantic. These are three rivers that can move in different directions.
So at times the currents flow in opposite directions, Mr. Cressy said.
"Traditionally, in the past, the high tide came into Edgartown Harbor from Nantucket Sound. Now, most of the time it comes in from Norton Point beach. Which means the currents in the harbor are reverse what they used to be," Mr. Cressy said.
Today the rising tide comes in first from the South. And just as that high tide comes to an end, the tide rising in Nantucket Sound is still flowing, so currents shift in Edgartown Harbor. Rising water starts coming in through the Edgartown Harbor from Nantucket Sound.
What baffles the boaters is that a rising tide can come from two directions.
As for trying to predict tides, Mr. Cressy said: "You can put your tide chart for Edgartown harbor out in the outhouse with your Sears catalog.
"It used to be that high tide at Wasque was an hour and a half different from Edgartown harbor," he said. "Now what happens is one tide comes in from the South, to its full extent. After that, water comes in from the North from Cape Pogue. Although one tide has finished, the other hasn't finished moving."
Mr. Hayes, Mr. Blake and harbor master Charlie Blair are both intrigued by the knowledge that there is a very short slack tide - it doesn't last more than 15 minutes. Water is almost always moving in the harbor.
Robert Eldridge White Jr. and his wife, Linda, are publishers of the Eldridge Tide and Pilot Book. The book has been published by his family for 133 years and his family's connection to the Vineyard goes back that long.
His tidebook is based on data collected and provided by the National Oceanic and Atmospheric Administration (NOAA), a federal branch of government offering ocean services which include tide and currents information. Mr. White warns: "NOAA is strapped for cash. What that means is that nobody is likely to be rushing over to Edgartown to collect new data any time soon."
Edgartown isn't alone. There are a number of places along the Atlantic seaboard where changes in geology require new adjustments to tidal data. NOAA is dropping data points.
Two years ago, Mr. White said, "Vineyard Haven was dropped from the list of ports for high and low because it was one of the many ports they had dropped. They dropped Marblehead, Manchester, Cuttyhunk and Menemsha, and yet they are all yachting centers. It was deemed that the data was so questionable nobody wanted to support it anymore.
"The government can't keep up with the demand for more recent accurate information," Mr. White said.
To meet the mariner's needs, Mr. White said his annual book of tides is published using data points that are old. And there are notices and asterisks in the book alerting reader to NOAA's actions.
"We have a bold box on page 12 saying that a number of substations have been dropped. We have put back some even though there is no data. We think that some information that is outdated is better than no data at all," Mr. White said.
Richard Edwing, deputy director of the NOAA National Ocean Service invites Edgartown harbormaster Mr. Blair to write his office a letter stating there is a need for new tidal data. Without that request there are no plans to do a survey.
"There are a lot of requirements and we don't have the resources to do them. There are needs in the Gulf Coast as a result of the hurricane [Katrina] and where some of the main commercial transportation centers are located. That is what we look at, but that doesn't mean we can't tag on a local project.
"But the first step is to let us know," he said.
What also complicates the issue is the history of the Norton Point opening. Through the centuries there have been many openings, and all of them migrated towards Chappaquiddick and eventually closed. Any Edgartown resident older than 50 years of age will remember the last opening and its eventual closing.
So for the summer, plans are underway to cope.
Mr. Hayes said one of his ferries, On Time II, is being upgraded from a 135 horsepower Ford engine to a 200 horsepower John Deere. The second ferry, On Time III, already has a 200 horsepower engine.
Mr. Hayes is looking at the option of getting new larger propellers next fall.
Mr. Blair has decided to discontinue having the water barge off North Wharf. For years visiting mariners could get free water at the barge, but now the currents there are just too strong. He is looking for a site inside the harbor.