Bonnet Carré Spillway until 1883. The Bonnet Carré Spillway consists of two basic components: a control structure along the east bank of the Mississippi River and a floodway that transfers the diverted flood waters to the lake. The control structure is a mechanically-controlled concrete weir that extends for over a mile and a half parallel to the river. When opened, the control structure allows overflow volume to flow into Lake Pontchartrain. The lake's opening to the gulf is sufficient to absorb and dissipate any conceivable volume of flood flow. Thus, the flood surcharge portion of the water from the Mississippi is divided between
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