CALGARY — The owner of the Keystone pipeline says a segment that ruptured in North Dakota has been isolated and the oil spill has been contained.
Calgary-based South Bow Corp. said Wednesday it estimates 3,500 barrels were released, equivalent to more than 556,000 litres. Its control centre detected a pressure drop on Tuesday morning and the system was immediately shut.
"On-site staff, the surrounding community and mitigating risk to the environment are South Bow's primary concern," the company said in a news release.
"Upon activating emergency response procedures, South Bow established around-the-clock air and environment monitoring. The company's response efforts focus on remediating the site."
The spill happened in a rural field about 100 kilometres southwest of Fargo, N.D.
More than 100 repair and cleanup workers were on site Wednesday, South Bow said in an online update. Multiple vacuum trucks are also on site to recover spilled oil.
It added that the pipeline was operating within its design and regulatory approval requirements when the rupture happened.
"South Bow will conduct a full investigation into the incident root cause while following all regulatory requirements," it said.
"We will continue to work closely with regulators, local elected officials, landowners and the community as the repairs and restorations are completed."
The Keystone system runs more than 4,300 kilometres from Hardisty, Alta., southeast of Edmonton, to the U.S. Gulf Coast in Texas. The Canada Energy Regulator says the pipeline transported an average of 624,000 barrels per day last year.
South Bow said it is evaluating a plan to return the pipeline to service, but gave no timeline.
Randy Ollenberger, head of oil and gas research at BMO Capital Markets, said the shutdown isn't affecting Canadian heavy oil pricing yet as there is ample room in storage tanks at Hardisty.
"As long as we don't have Keystone down so long that storage tanks start to fill up to capacity, it may not have much impact on the market," he said Tuesday.
An employee working at the site near Fort Ransom, N.D., heard a “mechanical bang” and shut down the pipeline within about two minutes, said Bill Suess, spill investigation program manager with the North Dakota Department of Environmental Quality.
No people or structures were affected by the spill, he said, adding a nearby stream that only flows during part of the year was not affected but was blocked off and isolated as a precaution.
The Keystone Pipeline was constructed in 2010 at a cost of US$5.2 billion by TC Energy, which spun off its crude pipelines into a new company, South Bow, late last year.
There have been 23 spills along the Keystone system.
One 2022 leak in Kansas dumped about 14,000 barrels of crude oil into a creek running through rural pastureland about 240 kilometres northwest of Kansas City.
An expansion to the system called Keystone XL would have increased the amount of crude flowing to Gulf refiners by cutting diagonally across Montana, South Dakota and Nebraska.
The expansion was first proposed during the Obama administration, which rejected it on environmental grounds.
It was then revived under the first Trump administration, before former president Joe Biden killed it again by revoking the pipeline’s permit on his first day in the White House in 2021.
U.S. President Donald Trump has said he wants to see that project revived, but South Bow says it has "moved on."
— with files from The Associated Press.
This report by The Canadian Press was first published April 9, 2025.
Companies in this story: (TSX: SOBO) (TSX: TRP)
Lauren Krugel, The Canadian Press
