Lake Oahe "a memorandum and an executive order asking USACE to expedite its consideration of the company’s application for an easement to start construction." The USACE subsequently "withdrew its call for the environmental study." On 7 February 2017, the USACE approved an easement through Lake Oahe. On 9 February 2017, the Cheyenne River Sioux filed the first legal challenge to the easement, citing an 1851 treaty and interference with the religious practices of the tribe. Lake Oahe Lake Oahe (oh-WAH'-hee) is a large reservoir behind Oahe Dam on the Missouri River; it begins in central South Dakota and continues north into North
Folsom Dam project that provides flood control, hydroelectricity, and irrigation and municipal water supply. In order to increase Sacramento's flood protection to 200 year flood protection (meaning that the area is protected from a flood that has a 0.5% chance of occurring in any given year) the US Army Corps of Engineers is constructing an auxiliary spillway. The spillway was completed by October 2017, and enables Folsom Dam to release water before it reaches the height of the gates already in place. Another Central Valley Project dam, Nimbus Dam, is located further down river. Folsom Dam is located just north of the