Activists resisting a controversial oil pipeline in a growing protest camp in Cannon Ball, N.D. hoped to hear a federal judge side with them Wednesday by issuing an injunction stopping its construction. Instead, they learned they may have to wait up to two weeks to hear the judge's decision.

In the meantime, the activists, who have formed a camp of largely Native American protesters that has swelled to more than 1,200 people, vowed to keep fighting.

They were joined in protest by a group of about 300 who gathered outside the U.S. District Court for the District of Columbia on Wednesday to urge Judge James Boasberg to issue the injunction. That group included environmental activists and celebrities, including Susan Sarandon.

The lawsuit, filed on behalf of the Standing Rock Sioux Tribe, sought a preliminary injunction to stop construction of the 1,172-mile Dakota Access Pipeline. An injunction would give the court time to assess the plaintiffs' claims that the pipeline violates the Clean Water Act and other federal statutes.

Boasberg is now expected to rule on the injunction by Sept. 9.

The pipeline builder Energy Transfer Partners did not respond to a request for comment. A company spokesperson told InsideClimate News last week that the pipeline is being constructed "in accordance with applicable laws, and the local, state and federal permits and approvals we have received."

The delay ensures continued tension between protesters and the company.

"I think folks are frustrated," said Tara Houska, national campaigns director for Honor the Earth, an indigenous environmental justice group. "I'm frustrated... [But] it is not going to dampen our efforts to ensure this pipeline" doesn't get built, she said.

Houska is among the activists camped out at Sacred Stone Camp, an impromptu community of trailers, teepees and tents four miles north of Cannon Ball.

Dallas Goldtooth, a campaign organizer for the Indigenous Environmental Network, said there was "confusion and bewilderment" in the camp when he announced the delayed court decision.

The $3.8 billion pipeline is designed to deliver 450,000 barrels of Bakken crude oil per day from North Dakota to Illinois, where it will be shipped to refineries on the Gulf Coast. Construction began this spring, and the project hasn't gained nearly as much national attention as the Keystone XL oil sand pipeline, which became a touchstone climate change issue and President Obama rejected last year. Unlike the Keystone, which would have crossed an international border, Dakota Access doesn't require presidential approval.

The pipeline route crosses the Missouri River near Cannon Ball, on the edge of the Standing Rock Sioux reservation. The tribe fears a pipeline spill would contaminate the river, which provides water for drinking and irrigation and plays an important role in its culture.

The grassroots campaign against Dakota Access launched in April when a few dozen people set up Sacred Stone Camp. After the section of the pipeline crossing waterways near the reservation was approved by the U.S. Army Corps of Engineers in late July, the activists sued to stop it. Hundreds more began to join the movement.

"It really is a temporary little town," said Houska, who drove from Washington, D.C. to Cannon Ball. "I've seen artwork displayed, concerts performed.... There is a sharing of culture, children playing together. It's a beautiful thing to see."

The chairman of the Standing Rock tribe, however, said local authorities have been increasingly hostile toward the protesters.

"In recent weeks, the state has militarized my reservation, with road blocks and license-plate checks, low-flying aircraft and racial profiling of Indians," David Archambault II wrote in an op-ed in The New York Times on Wednesday. "The local sheriff and the pipeline company have both called our protest 'unlawful,' and Gov. Dalrymple has declared a state of emergency."

A Lawsuit on Environmental Grounds

The tribe's lawsuit argues the Corps of Engineers failed to adequately survey for cultural artifacts along the route, or to fully account for the project's environmental impacts. The suit alleges violations of the National Environmental Policy Act, the Clean Water Act and the National Historic Preservation Act.

When protesters temporarily shut down construction near Cannon Ball last week, Energy Transfer Partners agreed not to resume building until after Wednesday's hearing, but the company did not comment on how it will respond to the delayed ruling.

Construction was also halted in Iowa, after state regulators ordered the company on Tuesday to stop building along part of its Iowa route, in response to a lawsuit from 15 landowners in the state. On Thursday, regulators denied the landowners' request, allowing construction to continue.

Energy Transfer Partners has claimed in court filings that more than half of the pipeline is already built, said Jan Hasselman, an attorney from the environmental law firm Earthjustice who filed the lawsuit for the tribe.

"We're really concerned," Hasselman said. "This company has pursued a strategy of getting this thing in the ground so fast that the rights of people to be a part of the process have been trampled on. The law gives the tribes important rights to protect sacred places and cultural heritage, and even if we're right ... by the time a court can vindicate them, it'll be too late."

Energy Transfer Partners has filed a separate lawsuit against the tribe to ban protesters from the construction site. A hearing on that suit was originally scheduled for Thursday, but is now postponed until Sept. 8.

Protest Goes National

Jane Kleeb, president of the activist group Bold Alliance, was among the protesters in Washington on Wednesday, where she said the mood was "very serious."

"It definitely did not feel joyous," she said. "But there was a strong sense of solidarity."

Kleeb said the court delay gives protesters more time to organize and put pressure on the White House to intervene.

Hasselman hopes President Obama is already aware of the pipeline's significance.

Obama visited Standing Rock Sioux reservation two years ago, and gave a speech on government-tribal relations in Cannon Ball, just a few miles from where Sacred Stone Camp lies today.

"He stood at a site where you could see the crossing of the pipeline [route], at the confluence of the Cannonball and Missouri Rivers," Hasselman said. "That's where the tribe hosted the president.... So we know the [White House] is aware of this."