A pipeline primer comparing British Columbia’s north and south coasts

Replacement pipe is stored near crude oil storage tanks at Kinder Morgan's Trans Mountain Pipeline terminal in Kamloops, B.C.CHRIS HELGREN/Reuters

Last week, the federal government made a decision on three pipeline projects, including two in British Columbia. Prime Minister Justin Trudeau announced Enbridge's Northern Gateway proposal on the province's north coast would be rejected. Kinder Morgan's Trans Mountain expansion pipeline to the south coast would move forward.

Groups opposed to the pipeline extension off the southern coast say they will protest until Trans Mountain is rejected like the pipeline in the north was.

But several geographical and logistical differences separate the two projects. Here are some of them:

Navigation

Enbridge's rejected Northern Gateway project would have had a pipeline run from Alberta to the northern B.C. port of Kitimat. Oil tankers would have departed from Kitimat, navigated the many turns south on the Douglas Channel before reaching the open water of the Hecate Strait – a total distance of approximately 160 nautical miles that can take up to 20 hours to navigate.

The West Coast Spill Response Study, prepared for the provincial government by Alaska-based consultants Nuka Research, describes the route as experiencing varying winds and currents. The 2013 study anticipated that Northern Gateway would introduce traffic of up to 250 tankers a year.

Tankers transporting oil from the Kinder Morgan pipeline on the south shore will travel a shorter distance of almost 90 nautical miles from the Vancouver Harbour to Victoria.

The shallow water of the Burrard Inlet means that large ships can make the trip only when the tides mean the water is deep and only during daylight hours, with the help of tug boats. The route also faces the challenge of passing under three bridges before reaching the Georgia Strait: a rail bridge and the Ironworkers Memorial, which post the greatest challenges, and finally the Lions Gate Bridge.

The spill-response study estimated that the Kinder Morgan expansion would increase traffic on the south coast by 408 tankers a year.

The Pacific Pilotage Authority says that the risks have been mitigated. Brian Young, director of marine operations for the organization, which trains pilots navigating the Pacific Coast, says tankers could have navigated both routes safely.

"What we've done since 2004 when we started doing these bigger tankers, we did a full risk assessment. We did simulations where the pilots go and work in simulators," Mr. Young said. "We know that we can do it safely because we had proposed mitigations for Enbridge and every other project."

Spill response

Environmental groups were concerned about the remoteness of the northern tanker route in the event of an oil spill.

"You have to get at it very quickly and that's a big difference between the north coast and the south coast," says Gerald Graham, a specialist in marine-oil-spill response with Worldocean Consulting Ltd.

There are few airports and ports in the northern region.

An accident in the north would occur far from the base of operations for the company that responds to oil spills.

Because a majority of large spills happen outside of port boundaries, it could take the Western Canada Marine Response Corporation up to 72 hours to be on the scene. By comparison, if a spill occurred in the Burrard Inlet, the WCMRC could be on the scene in less than six hours.

Northern B.C. also experiences heavier winds than the south shore does and winter storms could pose a greater navigational challenge for spill cleanup vessels.

"They couldn't even launch a response operation half of the time for Bella Bella," Dr. Graham said, referring to an Oct. 13 oil spill.

But for Karen Wristen, the executive director of Living Oceans Society, an environmental group, the less extreme weather conditions on the south coast are hardly a consolation for the environment.

"Regardless of weather conditions, the oil will already have begun to sink," she said. Once the spill is submerged, it's hard to keep track of until it resurfaces.

Whales

Some marine populations are at risk because of the increased traffic regardless of whether a spill occurs, environmentalists say.

The southern coast is home to a population of endangered killer whales that count less than 85. Research into feeding routes by the Raincoast Conservation Foundation found that the increased tanker traffic could mean that the whales would be subject to harmful noise pollution at all times.

"This population is on a precipice," said Misty MacDuffee, lead biologist at Raincoast. "Any further stressors will push it towards extinction."

She added that recovery is a possibility but it would involve increasing food availability and looking at long-term strategies of mitigating noise.

Along the northern tanker route, humpback and fin whales are also at risk, but they don't face the same crisis as the killer whale population.

The low population level of orcas off the south coast means that losing just one can have severe consequences to the survival of the species, biologists say.

Consultation

Pipeline opponents such as Art Sterritt of the Gitga'at First Nation are optimistic that the Trans Mountain project will eventually be rejected like Northern Gateway was.

"Just remember a few years ago the federal government announced the approval of Northern Gateway," Mr. Sterritt said. "The fact that they announced it doesn't mean everything is done. People will be heard."

But Kevin Hanna, director of the UBC Centre for Environmental Assessment Research, notes that the Kinder Morgan proposal has not followed the same trajectory as Northern Gateway so far.

"The big difference being that the government struck a ministerial review [of the Kinder Morgan project]," he said. "It was an extra layer of oversight that was used to help inform the final decision."

According to Dr. Hanna, the three-person ministerial review that the federal government introduced to the Kinder Morgan project will make it difficult to mount legal challenges similar to those faced by Northern Gateway.

He is skeptical that groups in opposition to Kinder Morgan will be able to point to the consultation process and argue that it was flawed.

"I don't think that's going to be successful."

Editor's Note: An earlier version of this story incorrectly said tankers from the Kinder Morgan terminal in Burnaby pass under two bridges before heading to the Georgia Strait. In fact, there are three bridges: two for vehicles and another for rail traffic. This version has been corrected.