Old River: Hydraulic Requirements

The streams and floodways in the Old River area form a complex system. Observed discharges and planned discharges illustrate the magnitudes involved. The control of the Old River has become necessary as a result of the possibility that the Mississippi River will adopt the course of the Atchafalaya River. The selection of a site for the control was influenced by several factors. An unusual situation exists with respect to the determination of prevailing and prospective tailwater conditions. The expected discharges through the structures are compared with natural flows. The structures permit the regulation of the flow, if required, to reduce the rate of enlargement of the Atchafalaya River, and will give assurance against the change of course of the Mississippi River.