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
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
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
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
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
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
Matthew 24: 38,39
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
The Engines of Our Ingenuity is
Copyright © 1988-1998 by John H.