A study commissioned by the Canadian government concludes that the passage of liquefied natural gas (LNG) tankers through the choppy waters of Passamaquoddy Bay, which straddles the US.-Canadian border, would involve a “considerable level of risk,” but it said that mitigation measures could significantly lower that risk.

The study, which was conducted by Senes Consultants Ltd. of Ottawa and released Tuesday, backs up what the Canadian government has been saying all along about LNG tankers using the bay and its entry, Head Harbour Passage, to reach U.S. terminals — that it’s dangerous, very dangerous. For this and other reasons, the Canadian government has threatened to block tankers trying to reach U.S. LNG terminals from using its waters.

“It is important to note that the passage of an LNG tanker…in Passamaquoddy Bay involves a very high level of risk. Risk-mitigation measures should be proposed and carefully analyzed before considering the passage of this type of vessel in this area,” the 300-plus page report said.

“Despite the existing difficulties,” the report noted that “transit from [a] proposed terminal is possible” if three types of mitigation steps are taken:

“The passage to [a] proposed terminal is difficult and the transit of a vessel transporting hazardous goods creates considerable risk.” But the “application of measures to mitigate risk in a risk-management approach could reduce the level of risk considerably,” the Canadian report said.

“As in the transportation industry, zero risk does not exist. The object is to manage the risk appropriately so that it is reduced to an acceptable level; however, the notion of acceptable risk has yet to be defined…Consequently, it is extremely difficult to arrive at a compromise to accommodate all of the parties involved,” the study noted.

The aim of the Senes study was to assess the potential impacts/risks associated with the development of LNG terminals on the U.S. side of Passamaquoddy Bay. A key focus was the impact that may result from marine traffic through Canadian waters, including approaches to the Head Harbour Passage and the bay itself.

The report zeroed in on two U.S. LNG terminal projects that are seeking to bring their cargoes through Canadian waters — the Quoddy Bay LNG project in Washington County, ME, and the proposed Downeast LNG terminal in Robbinston, ME.

It noted that tankers traveling to these terminal sites would face intense currents, strong winds, low visibility, as well as ice spray and waves. The vessels transiting through Head Harbour Passage will have to deal with an eddy known as Old Sow that is reputedly the largest eddy in the world, according to the report. “It reaches its maximum intensity approximately three hours before high tide and currents of up to six knots have been recorded outside of Deer Point. Consequently, this is a critical area in which vessels are required to change course by approximately 90 degrees.”

In addition, “from mid-November to March, the winds blow at an average of 20 knots and, during this period, gale force winds (more than 34 knots) occur 10 to 15% of the time and storm force winds 2% of the time…Winds measuring up to 70 knots have been recorded in Eastport, near the location at which a vessel sailing to Passamaquoddy Bay needs to undertake a major [maneuver].”

And visibility is often reduced to less than 0.5 nautical miles in any season, according to the report. “During the month of July, visibility that is reduced to less than 0.5 miles can be expected 20 to 30% of the time. During the winter, this percentage is less than 10% and is often caused by snow.”

©Copyright 2007Intelligence Press Inc. All rights reserved. The preceding news reportmay not be republished or redistributed, in whole or in part, in anyform, without prior written consent of Intelligence Press, Inc.