Johnstown Dam Disaster

The Johnstown Flood (locally, the Great Flood of 1889) occurred on May 31, 1889, after the catastrophic failure of the South Fork Dam on the Little Conemaugh River 14 miles (23 km) upstream of the town of Johnstown, Pennsylvania. The dam broke after several days of extremely heavy rainfall, releasing 14.55 million cubic meters of water. With a volumetric flow rate that temporarily equaled the average flow rate of the Mississippi River, 2,209 people, according to one account, lost their lives, and the flood accounted for $17 million of damage (about $463 million in 2017 dollars).

Dams Disasters
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