West Atchafalaya Floodway West Atchafalaya Floodway The West Atchafalaya Floodway is a flood control structure of the Mississippi River and Tributaries Project located in the Lower Atchafalaya Basin in south-central Louisiana. It has a project design flood flow capacity of . The Atchafalaya Basin system comprises three floodways. Two of these, the West Atchafalaya Floodway and the Morganza Floodway, are at the northern end. Together with the Atchafalaya River, these floodways are designed to pass flood waters into the third component, the Lower Atchafalaya Basin Floodway, which is in size and is bounded on the north by U.S. Route 190, on the east
Mississippi River Basin Model 1937, 1943, 1945 and 1952 were reproduced, as well as hypothetical floods at different periods of the year. Tests on individual problems were conducted until 1971 but high costs and growth of computer modelling meant that the facility was put on standby. The last use was in 1973, when a potentially catastrophic failure arose at the Old River Control Structure. The model was used to show that the untested Morganza Spillway could be opened effectively, without diverting polluted water through New Orleans and Baton Rouge, as well as identifying levees that required topping up. In 1993 the site was taken