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Johnstown Flood


JOHNSTOWN FLOOD of 1889 was the worst natural disaster in the United States. The city of Johnstown is located in southwestern Pennsylvania, in a narrow valley where the Little Conemaugh and Stony Creek rivers merge to create the Conemaugh River. In 1880, Johnstown was a leading industrial center with 10,000 inhabitants and 20,000 more in its surrounding communities.

In 1852, construction was completed on the South Fork Dam upstream on the Little Conemaugh River, creating a man-made reservoir. The dam gave way in 1862 and the damaged dam and surrounding property was sold. It was acquired in 1879 by the South Fork Fishing and Hunting Club, whose members were the wealthy elite from Pittsburgh and other eastern cities. From 1879 to 1881 the earth and rock dam was rebuilt, stretching 918 feet across and 72 feet high. The reservoir expanded to nearly three miles in length, one mile in width, and about sixty feet in depth at the dam face.

In late May 1889, torrential rains caused flooding in more than twenty western Pennsylvania counties. By 31 May, the water level climbed to within two feet of the top of the South Fork Dam, and it breached. The center collapsed, sending a wall of water one-half mile wide and seventy-five feet deep through the valley. Within another hour, the then forty-foot wall of water descended on Johnstown. The estimated 20 million tons of water was partially blocked at the Pennsylvania Railroad viaduct, creating a thirty-acre field of debris, drowned livestock, and human bodies, which eventually caught fire. In ten minutes, at least 2,209 people were killed (although contemporary records claim as many as 5,000), 1,600 homes damaged or destroyed, and the iron and steel factories ruined.

The New York Times of 1889 characterized the flood as "a symbol of the havoc created by the elements gone wild," while the London Chronicle condemned the shoddiness of American engineering. The dam lacked a core of masonry or puddle, and did not represent accepted construction practices even for the time. Survivors held the South Fork club members responsible, but the courts affirmed the disaster to be an "act of God" and no legal compensation was made to the survivors. The responsibility for the flood remains undetermined and has attracted the attention of numerous scholars.

Another major flood on 17 March 1936 caused $50 million in damage and resulted in a U.S. Army Corps of Engineers flood-control project in 1942. However, the city was again flooded in July 1977.


Ferris, George T. The Complete History of the Johnstown and Conemaugh Valley Flood. New York: H. S. Goodspeed, 1889.

Frank, Walter S. "The Cause of the Johnstown Flood." Civil Engineering 58, no. 5 (May 1988): 6366.

Johnson, Willis Fletcher. History of the Johnstown Flood. Bowie, Md.: Heritage Books, 2001. The original edition was published in 1889.

McCullough, David G. The Johnstown Flood. New York: Simon and Schuster, 1968.

Charles C. Kolb

See also Disasters ; Floods and Flood Control ; Hydroelectric Power ; Pennsylvania .

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