Existing comment:
The Dam Gives Way:
"The whole dam seemed to push out all at once. No, not a break, just one big push."
-- U. Ed Swartzentruver
In 1889, the dam gave way. Torrential rains filled the lake and the obstructed spillway could not discharge the water. Water flowing over the top eroded the dam until the pressure from the lake pushed it apart.
Telegraph operators at South Fork tapped out three messages on this telegraph key warning Johnstown of the danger. Few people heeded the warnings. They did not evacuate the town.
This photograph shows the broken dam and its height before the collapse.
The escaping water, flowing down the canyon, was constricted at spots and became a wall of water 70-75 feet high. It was 36 feet high when it struck Johnstown. The flood reached speeds of 40 miles per hour and averaged 15 miles an hour. Several times, choked by debris, it almost sopped. It took 40 minutes for the water to drain from the lake and 57 minutes to hit Johnstown 14 miles downstream. |