Morganza Spillway to open or shut any spillway gate or perform maintenance while the roadway is in use. The land on both sides of the Morganza Control Structure is above normal river water levels, and usually dry. In order for water to reach the spillway, the Mississippi must first rise well above its flood stage, overtopping its banks. The Corps of Engineers considers opening the Morganza Spillway when the flow of the Mississippi at Red River Landing, Louisiana, is greater than and rising. Water from the Mississippi is normally diverted into the Atchafalaya Basin at only one place, the Old River Control
120th Ohio Infantry May 1. Ordered to join Banks at Alexandria on Red River Expedition May 1. Embarked on steamer "City Belle". Action en route at Snaggy Point May 3. Over 200 men captured. Those who escaped were formed into a battalion of three companies and marched to Alexandria. Retreat from Alexandria to Morganza May 13–20. Mansura or Marksville Prairie May 16. Duty at Morganza until September. Expedition to mouth of White River and St. Charles September 13–20. Expedition to Duvall's Bluff, Ark., October 21–27. The regiment lost a total of 300 men during service; 2 officers and 17 enlisted men killed or