After years of study by TC Energy of Canada, key regulatory approvals, including a presidential permit, and the support of landowners, customers, indigenous groups and numerous partners in the U.S. and Canada, and just when the company, Keystone XL pipeline's principal proponent, thought all was said and done and construction on the last pipeline segments could commence, a U.S. federal court judge has revoked TC Energy's water-crossing permit needed to complete the construction of the pipeline.  This is a major setback.

A statement issued by the Sierra Club said that the decision could prevent construction “through hundreds of water crossings along the Keystone XL pipeline route.

“The court has rightfully ruled against the Trump administration’s efforts to fast-track this nasty pipeline at any cost. We won’t allow fossil fuel corporations and backdoor politicians to violate the laws that protect people and the planet,” said Tamara Toles O’Laughlin of the environmental group 350.org

The onus is now squarely on the US Army Corps of Engineers, which is obligated to suspend all filing and dredging activities until it conducts formal consultations compliant with the Endangered Species Act, leading to considerable delay and a rise in associated costs.

Judith LeBlanc, director of the Native Organizer Alliance, said: “The revoking of the permit is a victory for treaty rights and democracy. Tribal nations have a renewed opportunity to exercise our legal and inherent rights to protect the water of the Missouri river bioregion for all who live, farm and work on the land.”

This last segment of Keystone, a planned 1,897-km pipeline running from the oil sands of Hardisty, Alberta, to Steele City, Nebraska, will join an existing pipeline in Cushing, Oklahoma and end at Port Arthur, Texas. Keystone could carry 830,000 barrels of oil each day.

TC Energy is reviewing the ruling, said Terry Cunha, spokesman for the Calgary, Alberta-based company.

"We remain committed to building this important energy infrastructure project," said Cunha.