Construction of ice radar begins in Prince William Sound

Posted: Monday, November 05, 2001

ANCHORAGE (AP) -- Construction of the nation's first ice detection radar has begun on Prince William Sound.

The high-tech system is being installed on the island overlooking the site of the 1989 Exxon Valdez oil spill. When the work is completed, the system will be able to send out warnings about dangerous icebergs in the Sound.

The system is expected to start running early next year and tuned up over the next few years. It will use marine radar and a processor to scan tanker lanes for floating ice. The information will be instantly transmitted to Alyeska Pipeline Service Co. and the Coast Guard in Valdez.

Lt. Keith Ropella, chief of the Vessel Traffic Service, said the Coast Guard now relies on vessels going through ice at the time, usually an escort tug. He said the ice radar should give marine authorities a better idea of where the danger is.

The Exxon Valdez was trying to avoid reported ice when it struck Bligh Reef, spilling 11 million gallons into the Sound. Scientists and regulators say the danger has only gotten worse.

The problem was illustrated two weeks ago when a flotilla of bergs flushed across a submerged moraine and escaped Columbia's ice-choked fjord. No one saw them coming.

By about 2 a.m. on Oct. 20, the ice had spread south of Valdez Arm, forming an irregular blockade across the route used by tankers carrying crude oil from Alaska's North Slope. Only then did a mariner aboard an Alyeska escort vessel discover the ice-filled shipping lanes and radio the Coast Guard.

The Coast Guard restricted oil tankers to daylight travel, something the agency had already done for more than 1,300 hours this year. Alyeska's Ship Escort/Response Vessel System took extra precautions. In this instance, no tankers were due until about 9 a.m., Ropella said, and the ice floated away by afternoon. One empty tanker arrived and three full tankers departed without problems, SERVS later reported.

But the increasing danger posed by the drastic retreat of Columbia Glacier had once again threatened the transport of oil across the Sound. The glacier was a factor in the oil spill and a $1 million collision with an empty tanker in 1994.

So far this year, Alyeska has sent tugs or helicopters on 96 missions to scout for ice ahead of inbound tankers. The Coast Guard has allowed tankers to leave traffic lanes to avoid ice during 3,296 hours. Thick ice has closed the route for 79 hours spread over 11 days -- more downtime than in the previous four years combined.

The radar system is intended to help. A pair of U.S. Army Chinook helicopters are expected to haul the 50-foot radar tower to the Reef Island site early this week for erection by squads of Army engineers, said Rhonda Arvidson, project manager for the Prince William Sound Regional Citizens' Advisory Committee. Technicians will hook it up over the next few months.

The project was sponsored by the advisory group with support from state and federal agencies, the Coast Guard and U.S. Army, Alyeska, Prince William Sound Community College and Cordova's Oil Spill Recovery Institute. About $300,000 paid for the development of the new processor by the Center for Cold Oceans Resources Engineering of Newfoundland. But bringing everything together has drawn on about $2 million in volunteer effort and donated services.

''This is a huge project,'' Arvidson told the Anchorage Daily News. ''Getting this tower built is just like step one.''

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