The Missouri River originates in southwestern Montana and flows in a southeasterly direction about 2,315 miles to join the Mississippi River approximately 15 miles upstream of St. Louis, Missouri. The Mileage on the Missouri is measured upstream from the confluence of the Missouri and Mississippi rivers, mile 0.0.
Navigation on the Missouri River occurs from Sioux City to the mouth at St. Louis, a distance of 734 miles. In 1994, commercial barge traffic on the river was 1.5 million tons. Approximately 140 docks and terminals operate along the river. The Corps of Engineers has the responsibility under Congressional authorization for the construction, operation and maintenance of the Missouri River for navigation, flood control and related purposes, including flow regulation and bank protection. The Missouri River Bank Stabilization and Navigation Project provides a 9-foot deep, 300-foot wide navigation channel.
The commercial navigation season is normally from late March to early December. Specific Minimum flow rates are required during the navigation season to provide adequate depths and width. A flow of 30,000 to 35,000 cubic feet per second in generally maintained at Sioux City and Omaha. During insufficient natural flows, water is released from the upstream Mainstem Reservoir System.