Morganza Spillway Structure (ORCS), in use since 1963, where floodgates are routinely used to redirect the Mississippi's flow into the Atchafalaya River such that the volume of the two rivers is split 70%/30%, respectively, as measured at the latitude of Red River Landing. During the 1973 Mississippi flood, the ORCS was being damaged due to high flow rates, leading to the opening of the Morganza Spillway to help relieve this pressure. Subsequently, the nearby Old River Control Auxiliary Structure (ORCAS) was constructed, adding additional floodgates for use during major floods. The Morganza Spillway, about downriver from ORCS and ORCAS, is designed for
3rd Missouri Regiment of Colored Infantry Gulf, to September 1864. 2nd Brigade, 1st Division, United States Colored Troops, District of Morganza, Dept. of the Gulf, to February 1865. 1st Brigade, 1st Division, United States Colored Troops, District of Morganza, Dept. of the Gulf, to May 1865. Northern District of Louisiana, Dept. of the Gulf, to July 1865. Moved from Benton Barracks, Missouri, to Port Hudson, Louisiana, arriving March 19, 1864, and duty there till June. Moved to Morganza, Louisiana, and duty there till June 1865. Action at Mt. Pleasant Landing, Louisiana, May 15, 1864 (Detachment). Expedition from Morganza to Bayou Sara September 6–7, 1864. Moved to