"The Dakota Access Pipeline or Bakken pipeline is a 1,172-mile-long (1,886 km) underground oil pipeline project in the United States. The pipeline is currently under construction by Dakota Access, LLC, a subsidiary of Energy Transfer Partners, L.P. The minor partners involved in the project are Phillips 66, Enbridge, and Marathon Petroleum. The route begins in the Bakken oil fields in northwest North Dakota and travels in a more or less straight line south-east, through South Dakota and Iowa, and ends at the oil tank farm near Patoka, Illinois. The project was planned for delivery by January 1, 2017. On November 26, 2016, the project was reported to be 87% completed." Via Wikipedia
"Who's Fighting and Why?" An article on DAPL from the New York Times "
"The Dakota Access Pipeline Project is a new underground crude oil pipeline designed to transport 470,000 barrels of crude oil per day (with a growth potential up to 570,000 barrels per day) from the Bakken/Three Forks formations in North Dakota to a terminus near Patoka, Illinois. The project will require the construction of approximately 1,172 miles of 12-inch to 30-inch diameter pipeline through the states of North Dakota, South Dakota, Iowa and Illinois terminating near Patoka, Illinois. The project is supported by long-term binding contractual commitments from shippers and anticipates that the new pipeline and its related facilities will be ready for service in late 2016, pending regulatory approvals." From Energy Transfer Partners, the company building DAPL
"Standing Rock Sioux Nation straddles the North Dakota/South Dakota boarder on the western portion of both states. Currently the reservation is about 1,000,000 total acres." -- Standing Rock Sioux homepage
Why the Standing Rock Sioux Tribal Nation Brought a Lawsuit
"The Standing Rock Sioux Tribe is deeply concerned about the construction of a major crude-oil pipeline that passes through its ancestral lands. There are two broad issues. First, the pipeline would pass under the Missouri River (at Lake Oahe) just a half a mile upstream of the tribe’s reservation boundary, where a spill would be culturally and economically catastrophic. Second, the pipeline would pass through areas of great cultural significance, such as sacred sites and burial grounds that federal law seeks to protect.
The Tribe sued the U.S. Army Corps of Engineers, which is the primary federal agency that granted permits needed for the pipeline to be constructed. The lawsuit alleges that the Corps violated multiple federal statutes, including the Clean Water Act, National Historic Protection Act, and National Environmental Policy Act, when it issued the permits."