Old River Control Structure of 1973 almost caused the control structure to fail. Integrity of the Old River Control Structure, the nearby Morganza Spillway, and other levees in the area is essential to prevent such a diversion. Jeff Masters of "Weather Underground" noted that failure of that complex "would be a serious blow to the U.S. economy." The present Old River Control Structure was completed in 1964 and expanded in 1990. The first two floodgates are the Low Sill Control Structure, which regulates routine flow in the waterway, and the Overbank Control Structure, in use only when the Mississippi exceeds its banks. A navigation
1st Missouri Regiment of Colored Infantry of Morganza, Dept. of the Gulf, to September 1864. 2nd Brigade, 1st Division, United States Colored Troops, District of Morganza, Dept. of the Gulf, to September 1864. Port Hudson, La., Dept. of the Gulf, to September 1864. Brazos Santiago, Texas, to October, 1864. 1st Brigade, 2nd Division, United States Colored Troops, Dept. of the Gulf, to December 1864. Brazos Santiago, Texas, to June 1865. Dept. of Texas to March 1866. Ordered to Baton Rouge, La., March 23, 1864, and duty there till June. Ordered to Morganza, La., and duty there till September. Expedition from Morganza to Bayou Sara September 6–7.