ESTABLISHED: AUGUST 1964
The Johnstown Flood on May 31, 1889, was caused by the failure of the South Fork Dam which held back Lake Conemaugh. When the dam burst an estimated 20 million tons of water roared down the valley
- UNDERLYING CAUSES
- The dam was originally built in the 1840s for the state canal system, abandoned, and later bought by the private South Fork Fishing and Hunting Club (whose wealthy members included Andrew Carnegie and Henry Clay Frick).
- Previous owners had removed original bottom discharge pipes for scrap metal. The club lowered the dam’s crest to make it wide enough for a carriage road.
- The club installed iron mesh fish screens across the spillways to keep game fish from escaping, which quickly clogged with floating debris and branches during the storm.
- Unprecedented downpours dumped inches of rain per hour across western Pennsylvania, causing the lake level to rise rapidly past the clogged spillway until water breached and eroded the earthen wall.
I was surprised that this was not the first flood in Johnstown.
Old lake site
THANKS FOR VISITING, STEVE