TC said there is currently no timeline for the completion of repairs and the restoration of electrical service. The pipeline, with a capacity of 590,000 barrels per day, transports crude from Alberta to refineries in the American Midwest.
Calgary-based TC said force majeure on Keystone deliveries on Monday, but did not elaborate on the impact on volumes.
A pumping station near Huron, South Dakota, was closed due to damage to a third-party power utility on Sunday.