Flood of 1851

The Great Flood of 1851 occurred after record-setting rainfalls across the U.S. Midwest and Plains from May to August, 1851. Hardest hit was the State of Iowa, with significant flooding extending to the Lower Mississippi River basin. Historical evidence suggest flooding occurred in the eastern Plains, from Nebraska to the Red River basin, but these areas were sparsely settled in 1851. Heavy rainfall also occurred in the Ohio River basin.

Limited accounts from western regions suggest flooding was bad in eastern Nebraska, but this area was sparsely settled and therefore there is little information. Indirect evidence for flooding can be seen in historical accounts, for example, the flood knocked out a bridge at Shell Creek, Nebraska.

Iowa was the state most affected by the Flood of 1851. Flooding in Iowa was probably exacerbated because the Des Moines River basin, where the worst of the flooding occurred, had been settled for less than 10 years. Residents had never previously experienced a major flood, and river towns lacked levees and substantial bridges that could withstand flooding.

In 1851, 74.5 in (191.5 cm) of rain fell in Iowa, a record that holds to this day. The worst flooding occurred May to June in the Des Moines River Basin, and early August in eastern Iowa. Major rivers included the Cedar, Iowa, Skunk, Maquoketa, and especially the Des Moines rivers. Major flooding in 1851 occurred in Bentonsport, Croton, Bonaparte, Des Moines, Eddyville, Farmington, Iowaville, Keosauqua, Muscatine, Oskaloosa, Ottumwa, Red Rock, and Rochester.

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