Youth play in the Oceti Sakowin camp on the banks of the Cannonball River in N.D. Since April 2016, thousands of Native and non-Native protesters have joined the Standing Rock Sioux Tribe in their fight against the construction of the Dakota Access Pipeline. If built, the pipeline will be laid under the Missouri River, located on the edges of the Standing Rock Sioux Reservation. The pipeline threatens the availability of clean water and disrupts sacred sites and burial grounds. September 10, 2016.