Engines of Our Ingenuity
No. 1391:
THE JOHNSTOWN FLOOD

by John H. Lienhard

Click here for audio of Episode 1391.

Today, a dam breaks. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

It's 1889. The South Fork Creek dam and its reservoir, up in the western Pennsylvania hills, belong to a posh country club based in Pittsburgh. Andrew Carnegie is a member. From there it's 14 miles down the South Fork to Stony Creek. Hills rise sharply on either side. You wind under a 76-foot railroad viaduct, pass a half dozen towns, and finally arrive at Johnstown, population 30,000.

In 1856, a promoter named William Kelly returned to his native Johnstown with claims to've invented a new steel-smelting process. In fact, he'd created only one part of the Bessemer process. Speculators invested in Kelly. But, when they established the Cambria Steel Company, they used Bessemer's equipment and Andrew Carnegie's money. Johnstown mushroomed into a major steel town.

The South Fork Creek dam, finished in 1852, was 930 feet wide and sixty feet high. It held a lot of water. And it had a troubled history. It underwent restoration and repairs, but never quite enough. Its custodians, the so-called Bosses Club, were unconcerned. It was a pure earth dam with no masonry reinforcement. The Club had stocked the lake with fish, and, to keep them from escaping, they'd put a screen of iron bars across the overflow spillway. Trash accumulated and plugged up the screen.

Late May rains were heavy in 1889. On May 31st indications were ominous -- water rising, bridges washed out. Finally, around noon, a message from a telegraph operator at the dam reached Johnstown.

South Fork Dam is liable to break.
Notify the people of Johnstown to prepare for the worst.

The Johnstown freight agent shrugged it off. At 1:52 a telegram announced that water was overflowing the dam. At 2:45 a third telegram came. It said the dam was about to go. Johnstown's citizens were putting all their energies into moving rugs off floors as the creek rose. They had no conception of what would happen when a body of water one mile by three and sixty feet deep got loose.

At first, water flowing over the dam cut a notch. The notch quickly deepened. Then, around 3:15, water simply pushed the two sides apart, and the whole reservoir fell into the South Fork Creek bed. Water started down the valley at about 30 miles an hour. It rode over the top of that 76-foot viaduct. It drove anything loose before it. By the time it reached the towns above Johnstown, a black cloud of dust obscured a mountain of racing water.

Hundreds of eyewitnesses give an inkling of the horror. Houses exploding, people crushed by trees or railway cars. The terrible sound. Acts of heroism glimpsed out of the corner of an eye.

The dead numbered somewhere between 2200 and 2500; who can know for sure! As a horrified nation closed in on the carnage, one glimpse of heroism was Clara Barton. Here her new American Red Cross met its first major challenge. She moved in to build food kitchens, hospitals, and housing. The light at the end of this awful tunnel was a major new force for easing human suffering.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

(Theme music)


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

McCullough, D. G., Run for Your Lives! American Heritage, Vol. XVII, No. 4, pp. 4-11, 66-75.

For another story about a dam break disaster, see Episode 1325.

For as in the days that were before the flood they were eating and drinking, marrying and giving in marriage, until the day that No'e entered into the ark,

And knew not until the flood came, and took them all away; so also shall the coming of the Son of man be.
Matthew 24: 38,39


The Engines of Our Ingenuity is Copyright © 1988-1998 by John H. Lienhard.