Lawyers for the protestors have warned the decision could yet be appealed or overturned by the Trump administration after the President-elect is sworn into office
Environmental activists in North Dakota are celebrating this morning after a controversial oil pipeline project was denied a permit following months of protest.
The decision from the US Army Corps of Engineers is being greeted as a major victory for the Native American Standing Rock Sioux Tribe who have objected to the pipeline over fears it could contaminate the water source and destroy sacred sites.
The 1,885km Dakota Access Pipeline - which runs across three states - was close to completion with the final segment planned to run under Lake Oahe, a reservoir formed by a dam on the Missouri River.
The pipeline is 30 inches in diameter and is projected to transport approximately 470,000 barrels of oil per day, with a capacity as high as 570,000 barrels.
The pipeline was set to cross the river a half-mile from the Standing Rock Sioux reservation border.
The final stretch required an easement from federal authorities which has now been denied - although lawyers for the protestors have warned the decision could yet be appealed or overturned by the Trump administration after the President-elect is sworn into office.
Environmental activists have for months stood alongside the Native American Tribe in what has become an increasingly fractious dispute over the segment.
The protests grew over time, with hundreds of veterans flocking to the camp in recent days to stand against what they said were aggressive law enforcement tactics
North Dakota police have defended their use of rubber bullets and water cannons during demonstrations with thousands of military veterans flocking to the camp in recent days to stand against what they said were aggressive law enforcement tactics.
The veterans had pledged to act as human shields in the camp if the dispute continued.
The US Army’s assistant secretary for civil works, Jo-Ellen Darcy said the decision to deny the permit was based on a “need to explore alternate routes” for the pipeline across the reservoir.
It is as-yet unclear what the alternative routes may be.
"Although we have had continuing discussion and exchanges of new information with the Standing Rock Sioux and Dakota Access, it's clear that there's more work to do," Darcy said.
"The best way to complete that work responsibly and expeditiously is to explore alternate routes for the pipeline crossing."
The Army Corps will now undertake an environmental impact statement with "full public input and analysis.”
In a statement, the pipeline developer Energy Transfer Partners and its partner Sunoco Logistics attacked the Obama administration over the decision and said it remained committed to completing the project without a reroute.
"The White House’s directive today to the Corps for further delay is just the latest in a series of overt and transparent political actions by an administration which has abandoned the rule of law in favour of currying favour with a narrow and extreme political constituency,” the statement read.
A number of republican politicians have come out against the decision with the party's Speaker of the House of Representatives, Paul Ryan calling it, "big-government decision-making at its worst."
This is big-government decision-making at its worst. I look forward to putting this anti-energy presidency behind us. https://t.co/Qu0nFTmGZv— Paul Ryan (@SpeakerRyan) December 5, 2016
Standing Rock Sioux Tribal Chairman Dave Archambault II said “all of Indian Country will be forever grateful to the Obama Administration for this historic decision.”
“We wholeheartedly support the decision of the administration and commend with the utmost gratitude the courage it took on the part of President Obama, the Army Corps, the Department of Justice and the Department of the Interior to take steps to correct the course of history and to do the right thing,” he said.
"We thank the millions of people around the globe who expressed support for our cause.
“We thank the thousands of people who came to the camps to support us, and the tens of thousands who donated time, talent, and money to our efforts to stand against this pipeline in the name of protecting our water.”