Tide levels around Bermuda have been higher than usual for several weeks but residents and scientists have claimed there is no need for concern.

Ferry riders last week told The Royal Gazette that the tides in Hamilton Harbour have been high for well over a week.

And last night a ferry rider said high tides required passengers to embark and disembark the ferry via step ladder. She said the ferry operator said they do not make use of the ladders often.

In follow-up calls to residents who live near the water, it was revealed that high tides up to six inches above the average have been occurring for three to four weeks across the Island.

Yesterday Portofino Restaurant owner Cesare Maranzana said boaters have experienced problems travelling through Flatt's Bridge because of the rise in the tides.

And the Harrington Sound resident said he knew of a visitor who was unable to enjoy the beach near the Grotto Bay Beach Hotel because of the high tides inundating the beach.

Yeaton Outerbridge, who lives in Hamilton Parish, said there was normally about 12 feet of sand on his beach but due to the high tides the beach area has been cut back to three feet. He said he believed the tides have risen four or five inches above the normal level.

"I have been living in Harrington Sound for the last 36 years and, except for storms, I have never seen the tide as high as it is now for July and August," he said.

And Mr. Outerbridge agreed that the high waters beneath Flatt's Bridge has made it difficult for boats to travel beneath it.

But Harrison `s Marine Repair owner Richard Harrison said it has only been a little more difficult to get through Flatt's Bridge.

He said the tides have only been slightly higher than normal at only four or five inches higher than the real peak over the last three or four days.

"It's backing back now so I would think it's a normal occurrence," he said.

Scientists have claimed that recent higher tide levels around the Island were being caused by a high pressure system near Bermuda.

Rodney Johnson of the Bermuda Biological Station for Research last week said the strong anticyclonic mesoscale eddy, also known as a high pressure system, began to influence the sea level in Bermuda in early July.

"The eddy is now sitting over the top of Bermuda with a 35 centimetre signal," he said. This means the average sea level in Bermuda is currently 35 centimetres higher than normal due to the ocean eddy.

Mr. Johnson, who is the programme manager for the Bermuda Atlantic Time-Series Study (BATS), said the high pressure system does not affect tidal range (the difference between high tide and low tide). However, as it displaces the average level of the waters around Bermuda, it creates the higher tides (both high and low) that have been seen recently.

"It's analogous to a hurricane," he said, explaining that when the eye of a hurricane passes over, the effect is similar.

To put that into perspective, the moon normally pulls the tide about 33 centimetres, and the tidal range is typically about a metre, depending on the time of year.

"It's not the first time this has happened," said Mr. Johnson. However, "we are coming off the spring tide now", and the combination of the ebbing spring tide with the anticyclonic eddy has resulted in the unusually high tides.

"We can monitor it by satellite," he said. "It will probably last just another few weeks. We've been getting lots of questions about it - it is not due to global warming."

Bermuda Weather Service spokesperson Wayne Little also said that a tidal bulge happens fairly regularly and simply means that the sun and moon are closer together in the sky.

And when asked why tides have remained so high for longer than a week he said that it can occur when there is little breeze to move the water out of an area, such as Hamilton Harbour and Harrington Sound. Mr. Outerbridge noted that the water seemed not to be dissipating in Harrington Sound.

Most people contacted agreed that there was no real cause for concern as the higher tides were simply caused by nature.

Manager at the Riddell's Bay Esso Marina Station Michael Douglas-Hassell said that, while they have been a problem, there is not concern for the safety of the boats in their care.

"I don't see anything to be alarmed about. It's only a concern if we had a hurricane while the tides are doing that."