Morganza Spillway emergency use to divert additional water from the Mississippi River into the Morganza floodway, which merges downstream with the Atchafalaya floodway before entering the Gulf. Diversion of water from the Mississippi's main channel has the effect of lowering water level in the Mississippi downstream of the spillway, helping to relieve stress on levees and other flood control structures both upstream and down. Besides controlling flooding in a given event, the system is also designed to prevent the Mississippi River from permanently altering course down the Atchafalaya River, bypassing Baton Rouge and New Orleans. Water that passes the Morganza Spillway first
69th Indiana Infantry Regiment until October. Western Louisiana "Teche" Campaign October 3-November 30. Ordered to Algiers December 13, then moved to Texas December 18. Duty at Matagorda Bay and Indianola until February 1864, and at Matagorda Island until April 19. Moved to New Orleans, thence to Alexandria, La., April 19–27. Red River Campaign April 27-May 22. Actions at Alexandria April 29 and May 2 to 9. Graham's Plantation May 5. Retreat to Morganza May 13–20. Duty at Morganza until December. Expedition to the Atchafalaya May 30-June 6. Expedition to mouth of White River and St. Charles, Ark., September 13–20. Moved to Dauphin Island, Mobile