08:39 AM EDT, 04/09/2025 (MT Newswires) -- South Bow ( SOBO ) edged higher in pre-market New York trading after the company on Wednesday said its Keystone pipeline remains shut in following a day-prior breach in the line near Fort Ransom, North Dakota.

The company, spun off last year from TC Energy (TRP.TO) to hold its liquids pipelines, said the line break at its milepost 171 spilled about 3,500 barrels of oil and was shut down on Tuesday morning after sensors detected a drop in pressure.

"Aligned with incident protocols, South Bow ( SOBO ) initiated a shutdown and response at approximately 7:42 a.m. CT on April 8, 2025, after control center leak detection systems detected a pressure drop in the system; the system was shut down at 7:44 a.m. CT on April 8, 2025. The affected segment has been isolated, and the release has been contained," it said in a release.

The pipeline, which carries 591,000 barrels per day of oil sands crude oil from Alberta to refineries in Illinois, Oklahoma and the gulf coast, has had several spills since entering service in 2011, including a 2022 breach that spewed 14,000 barrels of oil into a Kansas creek. An investigation concluded a welding flaw and pressure on the pipe caused the break.

South Bow ( SOBO ) did not say why the line breached and has not offered a timetable for a return to service which will require permission from the U.S. Pipeline and Hazardous Materials Safety Administration. Other pipelines may be able to handle some of the shut in barrels, but U.S. refiners may need to seek alternative supplies until repairs are complete.

"From a basin perspective, Western Canada has excess pipeline capacity (post-TMX expansion), but a prolonged outage could result in a shortage of ~200mbpd. We think competing egress pipelines like TMX, (Enbridge's) Mainline, Express, Milk River, and Aurora could theoretically pickup ~400mbpd, leaving ~200mbpd to be absorbed by [Western Canadian] storage or moved out of the basin via rail," Tudor, Pickering, Holt analyst AJ O'Donnell wrote.

The company's shares were last seen up US$0.17 to US$22.00 pre-market. They closed down $2.15 to $31.10 on Tuesday on the Toronto Stock Exchange.