Trials aim to cut large wave generated by ferry

DUBLIN Port is conducting trials with Stena Line's "superferry" in an attempt to reduce the large wave caused by the vessel's approach to shore. It has already been agreed to halve the speed of the Dun Laoghaire Holyhead craft some three miles off the ferryport.

This follows a potentially serious incident at the Irish Lights depot in Dun Laoghaire Harbour, when seas are reported to have surged towards the dock where navigational buoys are stored and loaded. Earlier this summer, the Dun Laoghaire Rathdown local authority erected signs warning the public to stay away from the shoreline during, and for up to 20 minutes after, the Stena Explorer's arrival, due to the occurrence of "sudden, large waves".

The pressure wave is generated across Dublin Bay by the turbulence of the catamaran, which travels at 40 knots with 100,000 horsepower engines. Swimmers and small boat owners at Bulloch Harbour in Dalkey had complained of "eight to 12 foot" seas, but there were no reports of accidents, according to the authorities. Dublin Port's pilotage jurisdiction extends to the ferryport, although Dun Laoghaire has its own harbourmaster and harbour authority.

Capt Bob Wiltshire, Dublin Port harbourmaster, told The Irish Times the trials were proving very successful. Various combinations of speed and direction had been tested to try to eliminate the wave, and it had been reduced considerably, he said. "We are looking at it very seriously."

The Siena Explorer has been dropping its speed to 20 knots at the Burford Bank, some 31/2 miles off Dun Laoghaire, as part of the experiment. "It is a very slow process, because we can only observe the conditions in calm weather and at high water," Capt Wiltshire said. However, there might be no solution to the turbulence caused by the vessel's manoeuvres in the harbour before docking, he added.

A Stena Line spokesman said it was working in close association with Dublin Port. A Sandycove swimming club had recently informed it that conditions had improved, the spokesman said. The High Speed Super (HSS) ferry was still experiencing a few mechanical teething problems, which caused one cancellation last week, but it was still making an average of five trips a day. Its latest HSS has been introduced on its northern route.

In a separate development, Stena Line says it is "aware" of abuses of its boarding card system on the ship. Passengers with unused duty free allowances have been pressurised by other travellers into surrendering their cards. There is no permanent Customs point at Dun Laoghaire, but the Revenue Commissioners have a "flying squad" monitoring system.

Claims that passengers were being prevented from bringing their own food on board were without foundation, according to the spokesman. "Obviously, one does not bring one's own food into the ship's restaurant. But I've brought sandwiches on board myself," he said.