Morganza Spillway weir, two sluice gates, seventeen scour indicators, and 125 gated openings which can allow up to of water to be diverted from the Mississippi River into the Atchafalaya Basin during major floods. The project was completed in 1954. A highway (Louisiana Route 1) and the Kansas City Southern Railway cross the structure The Corps of Engineers maintains the structures and, in times of flood, monitors their piers for scouring and stability. The Corps of Engineers has two 25-ton cranes used to lift and lower the flood gates. The cranes roll on special tracks next to the roadway, enabling the operators
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