The Ten Costliest Floods In American History

Print Email

The Ten Costliest Floods In American History


10. The Great Mississippi Flood of 1927
> Date: April-May 1927
> Area or Stream With Flooding: Mississippi River from Missouri to Louisiana
> Reported Deaths: Unknown
> Approximate Costs: $2.89 Billion
> Cause:  Heavy rain and failed levees

In the summer of 1926, heavy rain soaked the Mississippi River Basin, causing it and and its tributaries to swell and break through the levee system in several states. The Cumberland River rose an estimated 56 feet, a level that remained a record for decades. The flood covered 27,000 square miles in ten different states. At the peak of the flood, 14% of the state of Arkansas was under the river. Then-Secretary of Commerce Herbert Hoover came into national prominence because of the disaster and later rode this fame to the presidency.  The flood also caused an exodus of African Americans from the South to major cities in the North, particularly Chicago, an event called “The Great Migration.”

9. The 1964 Flood in the Pacific Northwest
> Date: December 1964-January 1965
> Area or Stream With Flooding: Pacific Northwest
> Reported Deaths: 47
> Approximate Costs: $3.02 Billion
> Cause: Melting snow and heavy rain

In December of 1964, heavy snows covered the Western Cascade mountains in Oregon. Mid-month, the area was hit with unseasonably warm temperatures that melted the snow at the same time as nearly a foot of rain fell over the region in just a few days. The heavy waters coming down from the mountains flooded a vast region of the state of Oregon, including the entire town of Salem, which was submerged under nearly 10 feet of water. The flood would not subside until early January, and affected major parts of Oregon, as well as parts of California, Washington, Nevada, and Idaho. Over 150,000 acres of land were covered by the flood waters.


8. The Statewide Ohio Flood
> Date: March-April 1913
> Area or Stream With Flooding: Ohio, statewide
> Reported Deaths: 467
> Approximate Costs: $3.25 Billion
> Cause: Heavy rainfall

Excessive rainfall in March 1913 caused water systems all over the state, particularly the Great Miami River, to flood their banks. As the name of the flood suggests, no major part of the state was spared.  The disaster killed 467 people and damaged more than 40,000 homes were destroyed. The city of Dayton may have received seen the worst of the disaster, with its main street submerged by ten feet of rapidly moving water. The sudden flood in Dayton killed hundreds of unsuspecting people. Near Cincinnati, the Ohio River rose more than 21 feet in a 24-hour period. The Statewide Flood is considered by many to be the greatest natural disaster in the history of Ohio.

7. The Willamette Valley Flood of 1996
> Date: December 1996-January 1997
> Area or Stream With Flooding: Pacific Northwest and Montana
> Reported Deaths: 36
> Approximate Costs: $3.47 billion
> Cause: Melting snow and heavy rain

The Winter of 1995 was a strange one for the Willamette Valley in Western Oregon, as consistent, steady rain, rather than snow, raised the water table significantly through January. Towards the end of the month, several feet of snow blanketed the area. When a quick temperature shift caused the new snow to melt all at once, the already high river levels reached a breaking point. The flooding spread into Idaho, Washington, and California. The Willamette River immediately reached a peak of 28 feet near Portland. Roughly 30,000 residents were forced to flee.

6. The 1965 Flood of the South Platte River
> Date: June 1965
> Area or Stream With Flooding: South Platte and Arkansas Rivers in Colorado
> Reported Deaths: 24
> Approximate Costs: $3.94 billion
> Cause: Extremely heavy rain in a short period of time

On June 16, 1965, rain from a series of violent thunderstorms fell across parts of the state, with unprecedented rainfall levels of more than a foot in a single night. This caused the South Platte River to become a massive flash flood of 15 foot high water, sweeping through the entire course of the riverbed from Littleton, Colorado, all the way north to the border of Nebraska, destroying everything in its path. At its peak the river was reportedly 25 feet above normal water levels. All 26 bridges in the path of the raging river were ripped to shreds and carried away.