Demonstrators gathering in Kirkland to protest Dakota Access Pipeline

Protesters are gathering in in Kirkland in support of the Standing Rock tribe and others who oppose building oil pipelines near an American Indian reservation in North Dakota.

The Corporation in Kirkland is one of two companies with contracts to construct the Dakota Access Pipeline.

Demonstrators will be at The Corporation from 11:30 a.m. to 1 p.m. Tuesday.

Energy Transfer Partners CEO Kelcy Warren, the head of a Texas company building the $3.8 billion pipeline said in a memo to employees that the four-state, 1,172-mile project is nearly 60 percent complete and that "concerns about the pipeline's impact on the local water supply are unfounded." The Standing Rock Sioux tribe and others argue the project will impact drinking water for thousands of tribal members and millions downstream.

Standing Rock Tribal Chairman Dave Archambault II said he and the thousands of others who have gathered at an encampment in southern North Dakota to protest won't budge.

"People are still coming down here and are committed to stopping the project," he said.

The Standing Rock Sioux is challenging the Army Corps of Engineers' decision to grant about 200 permits at water crossings for pipeline, which goes through the Dakotas and Iowa to Illinois. The tribe says the project will disturb sacred sites and impact drinking water.

Energy Transfer Partners disputes those claims, saying the pipeline would include safeguards and that workers monitoring the pipeline remotely could close valves within three minutes if a breach is detected.

The tribe's effort to temporarily block construction near its reservation on the North Dakota-South Dakota border was denied by U.S. District Judge James Boasberg on Friday. But minutes later, federal officials ordered a temporary halt to construction on Army Corps land around and underneath Lake Oahe — one of six reservoirs on the Missouri River. Three federal agencies also asked ETP for a "voluntary pause" in work for 20 miles on either side of Lake Oahe.

The federal departments said the case "highlighted the need for a serious discussion" about nationwide reforms "with respect to considering tribes' views on these types of infrastructure projects."

Warren said the company had consulted with more than 55 tribes, including the Standing Rock Sioux, adding that ETP values and respects "cultural diversity and the significant role that Native American culture plays in our nation's history and its future and hope to be able to strengthen our relationship with the Native American communities as we move forward with this project."

Archambault said the consultations were one-sided and that "they met with us after their plans were already made."

The Associated Press contributed to this story.

KIRO