Great Mississippi River Flood, 1927
The Great Mississippi Flood of 1927 was the most destructive river flood in the history of the United States.
The flood began when heavy rains pounded the central basin of the Mississippi in the summer of 1926. By September, the Mississippi's tributaries in Kansas and Iowa were swollen to capacity. On New Year's Day of 1927, the Cumberland River at Nashville topped levees at 56.2 feet.
The Mississippi River broke out of its levee system in 145 places and flooded 27,000 square miles. The area was inundated up to a depth of 30 feet. The flood caused over $400 million in damages and killed 246 people in seven states.
The flood affected Arkansas, Illinois, Kentucky, Louisiana, Mississippi, Missouri, Tennessee, Texas, Oklahoma, and Kansas. Arkansas was hardest hit, with 14% of its territory covered by floodwaters. By May 1927, the Mississippi River below Memphis, Tennessee, reached a width of 60 miles.
As the flood approached New Orleans, Louisiana, about 30 tons of dynamite were set off on the levee at Caernarvon, Louisiana and sent 7,000 m³/s (250,000 ft³/s) of water pouring through. This prevented New Orleans from experiencing serious damage, but flooded much of St. Bernard Parish and all of Plaquemines Parish's east bank. As it turned out, the destruction of the Caernarvon levee was unnecessary; several major levee breaks well upstream of New Orleans, including one the day after the demolitions, made it impossible for flood waters to seriously threaten the city.
By August 1927, the flood subsided. During the disaster, 700,000 people were displaced, including 330,000 African-Americans who were moved to 154 relief camps. Over 13,000 evacuees near Greenville, Mississippi, were gathered from area farms and evacuated to the crest of an unbroken levee, and stranded there for days without food or clean water, while boats arrived to evacuate white women and children. Many blacks were detained and forced to labor at gunpoint during flood relief efforts.
Following the Great Flood of 1927, the Army Corps of Engineers was again charged with taming the Mississippi River. Under the Flood Control Act of 1928, the world's longest system of levees was built. Floodways that diverted excessive flow from the Mississippi River were constructed.
Reel 1, flood waters rage through Illinois, carrying houses and debris. Kleinwood, La., is under water. Marooned families, their salvaged possessions, and livestock cling to levees. Sec. of Commerce Hoover meets Red Cross heads. Army troops load equipment on freight cars. Levees are reinforced at Baton Rouge. Coast Guard cutters and miscellaneous craft evacuate people and animals in La. Reel 2, Hoover and Sec. of War Davis inspect flooded areas at Vicksburg and along the River to Natchez. Refugees are inoculated, fed, and given shelter at an Army camp in Louisiana.