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
175th New York Volunteer Infantry 26-30. Siege of Port Hudson May 30-July 9. Assault on Port Hudson June 14. Surrender of Port Hudson July 9. Moved to Baton Rouge July 22, and duty there until March 1864. Operations about St. Martinsville November 12, 1863. Red River Campaign March 23-May 22. At Alexandria March 25-April 12. Cane River April 23-24. At Alexandria April 26-May 13. Retreat to Morganza May 13-20. Mansura May 16. At Morganza until July. Expedition from Morganza to the Atchafalaya May 30-June 5. Atchafalaya River June 1. Moved to Fort Monroe, Va., then to Washington, D.C., July 5-29. Sheridan's Shenandoah Valley Campaign August