Atchafalaya River Morganza Spillway further downstream is also used to regulate volume. In 1942 part of the flow of the Atchafalaya River was diverted through Wax Lake to the Gulf of Mexico further west. During the 2011 Mississippi River floods, the Old River complex was discharging more than into the Atchafalaya River, and the Morganza Floodway was discharging one-fourth of its capacity. If the Mississippi were allowed to flow freely, the shorter and steeper Atchafalaya would capture the main flow of the Mississippi, permitting the river to bypass its current path through the important ports of Baton Rouge and New Orleans. Despite
Morganza Spillway 2011 event) had been opened by the Corps of Engineers. The Corps estimated the flow rate at . However, on May 25, new estimates from the U.S. Geologic Survey (USGS) described a much higher rate of , resulting in the closure of 3 bays by May 26, and additional closures by May 29, bringing the total to 11 bays with an estimated diversion rate of . The Corps continued to evaluate the flow and close additional bays as appropriate. By June 6, the number of open gates had been reduced to seven, and by June 8, only two gates were