Mississippi River River Control Structure and the Morganza Spillway in Louisiana, which direct excess water down the west and east sides (respectively) of the Atchafalaya River; and the Bonnet Carré Spillway, also in Louisiana, which directs floodwaters to Lake Pontchartrain (see diagram). Some experts blame urban sprawl for increases in both the risk and frequency of flooding on the Mississippi River. Some of the pre-1927 strategy is still in use today, with the Corps actively cutting the necks of horseshoe bends, allowing the water to move faster and reducing flood heights. The area of the Mississippi River basin was first settled by
Morganza Spillway still open. All bays were closed on July 7, 2011. The Corps had estimated that it would take opening one-fourth of the spillway’s 125 bays — or 31 bays — to control the flow of the river through Baton Rouge in response to a forecast crest of anticipated on Tuesday, May 17, 2011, which must remain below of water per second through Baton Rouge to ensure the integrity of the levee system. Since Morganza never operated above , the flooding in the Atchafalaya Basin was considerably lower than had been anticipated during the initial estimates of . By May 29,