Victory for Native Americans and climate activists who had been protesting against the $3.8bn project.
In a remarkable feat of organisation on Sunday, thousands of people joined hands and formed a ring, a “prayer circle” around a camp at the confluence of the Cannonball and Missouri Rivers.
They were there to pray and show their support of the Standing Rock Sioux Nation and other Plains Native tribes who objected to plans to put a crude oil pipeline across the Missouri.
The sun blazed on a snowy landscape and flags fluttered from hundreds of native tribes, activist groups and supporters from as far afield as the Canadian Arctic, Peru and Palestine. Then something remarkable happened.
A ring of people several kilometres long started cheering and raising their linked hands in celebration. The tribal chairman of the Standing Rock Sioux, Dave Archambault, had just accounted the decision by US Army Corps of Engineers to deny a permit to put the pipeline under the river, at least in the current spot.
“This is it, this is why we’ve come,” shouted Mary from Minnesota, a teacher. Arnie, a pigtailed member of the Ojibway tribe from the same state, said his prayers had been answered.
“This is about praying for peace, praying for the right outcome, using non violence instead of guns and anger,” he said. He and Mary kept their hands tightly linked even as they spoke.
Over at the council fire – one of the seven sacred sites of fire that give the camp its name in the Sioux language – people were packed in tightly around a drum circle. Members of the Standing Rock nation in traditional clothing pounded the bison skin drums and sang songs of healing and victory.
“A big shout out to all who came here to support us,” said a chief in full-feathered headdress. “To the veterans, the faith leaders, the people from all 50 states, Canada, Mexico and around the world. Thank you.”
War-whoops and cheers rang out. The mood was ecstatic.
But away from the crowd, there were murmurs of disbelief and scepticism. Chase Iron Eyes, a lawyer and member of the Standing Rock Sioux Nation, said his concerns were rooted deeply in Native American history, in the many broken promises of US governments over centuries.
“They are already violating our treaty by even considering this project,” he said. “This camp is on our land, the pipeline route on both sides of the river, goes through our land. This is only a small victory and we have to keep up this action, we can’t trust government or energy companies.”
Others spoke grimly of the company behind the Dakota Access Pipeline, Energy Transfer Partners, continuing to drill and dig a tunnel beneath the Missouri River along the route that the US Army Corps of Engineers had denied.
People suggested that any fines that might be levelled against the project for ignoring the denial of the permit would be miniscule and short-lived. An incoming Trump administration, they said, would just approve the project again and the whole cycle of construction, resistance and protest would continue.
Sure enough late on Sunday night, Energy Transfer Partners issued a scathing, almost contemptuous statement. It said the US Army Corps of Engineers had made an “overt political” and blamed the outgoing Obama Administration, which, it said, had been unsupportive of the project in the past.
The company suggested it would indeed ignore the ruling, that it was “fully committed to ensuring that this vital project is brought to completion … without any additional re-routing in and around Lake Oahe [the reservoir on the Missouri that the line was supposed to cross]”.
Then came the kicker.
“Nothing this administration has done … changes this in any way.”
It’s hard not to see that as a firm statement that work would continue, no matter what, and all barriers would be removed once President Donald Trump was in office.
Republican Party officials in North Dakota were no less blunt. One member of Congress, Kevin Cramer referred to the permit denial as a “chilling decision” and looked forward to next year when “adults” would be in charge in the White House.
As Monday morning dawned at the Oceti Sakowin camp, any air of celebration seemed to blown away by howling winds from the north. A snowstorm was the prelude to a week of deep Arctic temperatures. Trucks were still delivering firewood and men were making oil drums into stoves for warmth and cooking.
“We’re here for the long haul,” said one of those working on the stoves, “this isn’t over. We won’t leave until they do.” He pointed towards a line of hills to the north, where pipeline construction vehicles, floodlights and police Humvees were barely visible through the snow.
As he spoke, Reuters news agency was reporting that President-elect Donald Trump’s transition team said he would be reviewing the Army Corps of Engineers decision after he takes office in January.
As organisers here at the camp debate their next steps, it’s going to be interesting to see how many of the thousands now here will continue to brave the cold winds, and the resolve of a new government in Washington.