Mississippi flood of 1973 The Morganza Spillway was opened, flooding portions of the Atchafalaya River basin in Louisiana and causing the deaths of thousands of head of livestock and white-tailed deer. The 1973 flood was notable for nearly causing the failure of the Old River Control Structure above the Mississippi River Delta, which would have sent the Mississippi's main channel flowing into the Atchafalaya River and bypassing most of the delta region including the major port of New Orleans, Louisiana. In spite of record high flows, flood stages were not as high as past events. Red River Landing, Louisiana reached 58.22 feet on May
Spillway Spillway A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically the riverbed of the dammed river itself. In the United Kingdom, they may be known as overflow channels. Spillways ensure that the water does not overflow and damage or destroy the dam. Floodgates and fuse plugs may be designed into spillways to regulate water flow and reservoir level. Such a spillway can be used to regulate downstream flows – by releasing water in small amounts before the reservoir is full, operators can prevent sudden large releases