Heavy surf caused by Hurricane Bill brought “closed to swimming” signs to south-facing Island beaches all weekend, sanctions surfers cheerfully ducked. What the storm left was additional erosion, though the bigger loss may be economic, as many visiting boaters took off when they heard the warnings broadcast last week.

Norton Point Beach opening, a quarter-mile stretch of open water which has separated Chappaquiddick from Katama since 2007, seems to have remained unchanged despite the high seas and strong currents, according to Chris Kennedy, Islands regional director for The Trustees of Reservations. He visited the opening on Sunday.

Considerable overwash during periods of peak high tide took out snowfencing and signs, Mr. Kennedy said, but the remaining barrier beach system is holding despite its vulnerable state.

The opening is now half as wide as it was when the barrier beach first was breached in an early spring storm two years ago. Mariners have been watching it carefully because the bigger the opening, the stronger the currents in the harbor.

With a mild summer, Mr. Kennedy said the opening has shown signs of closing, though the currents this past weekend seemed a good deal stronger.

“The Edgartown side of the opening is moving eastward very rapidly [and] the Chappaquiddick side of the opening is receding much slower,” Mr. Kennedy said. The result of the two is that the opening is narrowing and migrating eastward as it has done many times through the centuries.

Mike Creato, a biplane pilot, flew over the beach yesterday and verified Mr. Kennedy’s observations from the ground. Mr. Creato said there were several areas where the ocean waves clearly crossed over the narrow barrier beach.

Mr. Kennedy said high astronomical tides over the weekend flooded the roads on the inside of Cape Pogue Pond and made them unusable. “It was amazing to see,” Mr. Kennedy said. The Trustees of Reservations owns Wasque Reservation and Cape Pogue Wildlife Refuge.

While it was understood on Friday that Hurricane Bill was going to pass up to 200 miles southeast of Nantucket sometime Sunday, public safety concerns about the surf caused Gov. Deval L. Patrick to announce the closing of beaches on Nantucket and on Martha’s Vineyard. The governor said that because of concerns about riptides and high 20 foot seas, beaches were being closed to swimming at noon on Friday. On Saturday morning a tropical storm warning was issued for the Cape and the Islands.

Marilyn Wortman, of the Edgartown parks and recreation department, said South Beach was closed to swimming on Saturday morning. Later in the morning, the beach was closed even to those who wanted to watch the heavy surf. The action was taken because the wash-over from waves kept coming in and covering the exposed beach. The beach remained closed through Sunday and was reopened to the public yesterday.

Long Point Beach, a Trustees of Reservations property, was closed on Saturday and Sunday because of the heavy surf. Alex Dorr, visitor service employee for the Trustees, said that there was overwash but not much change in the beach.

Lucy Vincent Beach and Squibnocket Beach also were officially closed, though the surfing grapevine was crackling with wave reports from Islanders who entered those waters from unguarded private access points.

The storm came closest to the Vineyard on Saturday night late. Showers continued until nearly dawn Sunday morning. The National Weather Service Cooperative Station in Edgartown registered .44 inches of rainfall.

Winds were light through the storm, though considerably higher gusts were recorded on sister island Nantucket.

Hurricane Bill’s biggest impact to the Vineyard may be economic. Vineyard Haven harbor master Jay Wilbur said he saw boats leave his harbor in advance of the storm, and they are not coming back.

“Most of the visiting boats went home. I think it is partly a function of the storm and schools starting early that caused the exodus,” Mr. Wilbur said. He said that 40 of 200 moorings in his town remain unoccupied.

“Have you heard the expression ‘Television Hurricane?’ All that hype that goes with the television. They are television hurricanes, not hurricanes at all,” Mr. Wilbur said.

It used to be that in his role of harbor master, Mr. Wilbur said he would pay attention to the serious weather forecasters and warn his boaters about storms that were real and approaching. From almost the beginning, the National Hurricane Center forecasted this storm would miss the Vineyard.

“Today, I don’t say a word, and the television scares the heck out of them,” Mr. Wilbur said.

Oak Bluffs harbor master Todd Alexander said the fear of Hurricane Bill essentially emptied the harbor of visitors and brought a loss of business for two days.

“I am glad it turned out the way it turned out. We are relieved,” said Edgartown harbor master Charlie Blair. He said he and his crew of deputy harbor masters began preparing for the storm on Wednesday, checking boats to make sure they had chaffing gear and were prepared. “Someday it is going to happen,” Mr. Blair said. “I remember Hurricane Carol.

“It is an economic loss when you scream hurricane. Right now we’ve got an empty harbor and empty docks. We got a few boaters back. I think we are one third full,” Mr. Blair said.

What is more astonishing to Mr. Blair is the negligence on the part of some boat owners. He said while many boat owners made sure their boats were prepared, a small percentage didn’t. “But you know there were quite a few who didn’t even go down and check their boats. Those are the boats that break loose and wipe out the others,” Mr. Blair said.