The Canadian government’s star marine safety expert says the west coast has little to fear from tankers that would be loaded with oil by the contested Trans Mountain Pipeline expansion project for the country’s top natural gas user, Alberta thermal oilsands production.

“The level of navigational safety is such that the release of large quantities of pollutants from vessel accidents is a very improbable outcome,” said John Clarkson in a brief filed with the National Energy Board (NEB).

Clarkson wrote as a veteran sea captain, crew trainer, civil servant and accident investigator that the federal cabinet in Ottawa appointed as marine technical adviser for the NEB “reconsideration” review of its 2016 Trans Mountain approval.

He urged the board to arrive at a realistic, sensible verdict in its court-ordered second look at the project’s environmental aspects by thinking “as experience indicates, in the context of an effective pilotage system such as Canada’s.”

Clarkson recited a stellar safety record maintained by Canada’s Pacific Pilotage Authority and the British Columbia Coast Pilots, as independent local expert guides for commercial vessels through the region’s busy ports and sea traffic lanes.

The west coast pilots scored a 99.97% standard of accident-free passages. Only 10 trouble incidents happened during 38,131 pilot assignments to ships navigating British Columbia (BC) waters in 2015, 2016 and 2017. None of the mishaps involved tankers.

Clarkson said vessels loaded at Trans Mountain’s Westridge Marine Terminal in Vancouver Harbor set a high standard even without added precautions in company plans and draft NEB approval conditions for the 66 year-old pipeline’s expansion project.

“In fact, pilots on the west coast of Canada have moved crude oil carriers without incident for over 50 years,” Clarkson said. He lives near the region’s orderly ocean traffic in his retirement home at Sooke on the southern tip of Vancouver Island.

The expansion plan’s extra tanker safety measures — double hulls, low speeds and tethers to strong tugboats — “offer a much higher degree of protection from being breached than other ships,” he wrote.

The project sounded alarms among environmental and aboriginal groups by proposing to triple Trans Mountain deliveries of Alberta oil to 890,000 b/d and increase overseas cargo loadings to 34 tankers and three barges per month.

Fear of oil spills by growing tanker traffic contributed to project delays that prompted the pipeline’s former investor-owner, Kinder Morgan Canada Ltd., to sell it to the Canadian government last summer for C$4.5 billion ($3.4 billion).

But tankers would remain less than 10% of west coast ship traffic after the pipeline expansion, Clarkson said.

“The current regulatory regimes provide an effective framework governing safety, security and environmental protection in relation to marine shipping,” he wrote. “There is, however, always room for improvement.”

Clarkson endorsed draft NEB recommendations for a cooperative marine risk assessment by the Canadian and U.S. governments, and safety education for recreational, fishing and small commercial boat sailors that navigate BC waters without professional pilots.