CANNON BALL, N.D.  — Oil could be flowing through the $3.8 billion Dakota Access pipeline in less than two weeks, according to court documents filed by the developer just before police and soldiers started clearing a protest camp in North Dakota where pipeline opponents had gathered for the better part of a year.

Energy Transfer Partners has finished drilling under Lake Oahe and will soon be laying pipe under the Missouri River reservoir, the Dallas-based company said.

“Dakota Access estimates and targets that the pipeline will be complete and ready to flow oil anywhere between the week of March 6, 2017, and April 1, 2017,” company attorney William Scherman said in the documents filed in Washington, D.C., on Tuesday.

The work under the Missouri River reservoir is the last stretch of the 1,200-mile pipeline that will move oil from North Dakota through South Dakota and Iowa to a shipping point in Illinois. ETP got permission for the lake work last month from the pro-energy Trump administration, though American Indian tribes continue fighting the project in court.

The Standing Rock and Cheyenne River Sioux tribes say the pipeline threatens their drinking water, cultural sites and ability to practice their religion, which depends on pure water. ETP rejects those claims and says the pipeline is safe.

The tribes have been fighting the construction since last summer, when an initial lawsuit was filed.

They have also asked U.S. District Judge James Boasberg to overturn permission for the river crossing; The Standing Rock Sioux filed a motion earlier this month, and the Standing Rock tribe filed a similar request on Wednesday. ETP didn’t immediately respond to the motions.

Several groups including the National Congress of American Indians and the Great Plains Tribal Chairman’s Association along with 34 other tribes on Thursday filed a court brief supporting Standing Rock’s request.