In the nick of time: Behind Trans Mountain’s longest shutdown

It would have been more than just flood waters to worry about had Trans Mountain not made the ultra-rare decision to turn off the pipeline.

The rain relentlessly hammers the ground, turning creeks into raging rivers. A mudslide exposes and visibly damages the Trans Mountain pipeline, which runs parallel to the washed-out Coquihalla Highway. Mud from the hillside mixes with rain water and a dark sludge: oil, which is pouring rapidly from the severed line. The water carries it all downhill, into the swollen river and valley below.

That, at least, is what could have happened. But there was no spill, with Trans Mountain making an ultra-rare decision to halt operation mid-storm that seemed to have prevented any oil from reaching the ground.

The Trans Mountain pipeline has been a point of contention in BC for years, as anyone who has heard about its controversial expansion project knows. But the biggest disruption to the underground oil- and gasoline-pumping machine didn’t come from activists, government or corporations, but from one very angry Mother Nature.

On average, the federally owned pipeline delivers about 300,000 barrels of crude and refined oil products each day through 1,150km of pipe. The line begins in Edmonton, winds through the Rocky Mountains and the BC Interior, and enters the Fraser Valley at Hope. It passes through Chilliwack, Abbotsford, and Langley en route to its terminal in Burnaby.

In short: the pipeline is located in some of the places that received the worst of November’s storms.

The province didn’t issue any emergency alerts before the first devastating November storm. But as the weather worsened on Nov. 14, landslides began destroying highways across British Columbia.

That same day Trans Mountain made the exceedingly rare decision to turn off the pipeline, which is responsible for 90% of BC’s fuel consumption.

Aside from a couple scheduled shutdowns for maintenance each year, it’s unusual for the pipeline to be offline. In fact, the last time the pipeline was closed due to inclement weather was in 1995, after extreme flooding in the Coquihalla area.

This time, some of the hardest hit areas during last month’s first storm were the Coldwater and Coquihalla valleys between Merritt and Hope. In those areas, multiple sections of pipeline were exposed. Other sections possibly need to be cut and replaced entirely, the company has said.

Trans Mountain crews found it difficult to access many damaged areas after the initial storm decimated roadways, and subsequent storms added to the challenges. Those obstacles underscored the potential risks if a spill were to occur in a spot that crews couldn’t quickly get to.

The delays in repairing the pipeline forced the province to extend BC’s fuel rationing orders. (Those finally expired at the end of day on Tuesday, Dec. 14.) But the work to restart the pipeline required more than just repairs to the infrastructure.

“The flooding caused the river to jump its banks and start running water along the right of way where the pipeline was. So our teams have been spending a lot of time and effort, re-diverting water courses to where they’re supposed to be,” Trans Mountain spokesperson Ali Hounsell said.

But the mountain landslides and river changes weren’t the only problems for Trans Mountain. After the landslides came flooding on Sumas Prairie, where Trans Mountain has a pump station east of Cole Road and south of Highway 1. The infrastructure pumps crude oil to the Burnaby terminal, as well as to Washington State. It is one of several pump stations along the route that help keep the product moving when pressure drops in the pipeline. (The company also has a tank farm on Sumas Mountain, just uphill from the pump station.)

The Sumas Prairie pump station is located in the area that was placed under an evacuation order, near the site of the former Sumas Lake. The company says that site escaped flood damage.

“It’s actually built up with quite a large berm around it, knowing the geography of the area,” Hounsell said on Nov. 29. “We had people at the pump station monitoring it 24 hours a day. But that station has remained dry.” Aerial photographs from Nov. 19 show the station on the dry side of a berm, opposite the vast waters of a reborn Sumas Lake.

A marker on an aerial photo of Sumas Prairie during the floods illustrates the location of Trans Mountain's Sumas pump station, which appears to have avoided the waters. 📷 Peregrine Aerial Surveys

The site, along with the tank farm on Sumas Mountain, are part of the controversial expansion project that will include about 980km of new pipeline.

Floods like those which occurred last month are expected to be more frequent as the climate changes in the decades to come. Peak flows on the Nooksack River, which caused the flooding in the prairie, are expected to rise by up to 25%. (For more on that, read Tyler’s story on how Mt. Baker feeds the Nooksack River.)

The Current asked Trans Mountain how the company is accounting for impacts of climate change in the construction of the expansion.

Hounsell said the company adjusted their design of river crossings to account for a 10% increase in flood and river flow–a guideline suggested by the Association of Professional Engineers and Geoscientists of the Province of BC.

Trans Mountain did not provide The Current with any information on whether last month’s flooding delayed construction on the expansion. But The Globe and Mail reported on Dec. 14 that the storm did force the flow of the Coldwater River to change enough that the company said it will need to redesign crossings. And further south, Trans Mountain’s construction staging area near Laidlaw was part of an evacuation alert on Nov. 29.

The existing pipeline, however, was restarted on Dec. 5, after its longest period offline in Trans Mountain’s 68 year history.

Since restarting, the pipeline has been running at a reduced pressure. Trans Mountain expects to deliver about 75% of its normal volumes to customers over the month of December, and estimates the pipeline will return to full capacity at the end of January–unless Mother Nature has something more to say.

More of our in-depth coverage of the 2021 Fraser Valley floods:

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