The Day the Mountain Moved

The South Fork Dam had been showing signs of weakness for years. Engineers warned. Letters were written. The dam held 20 million tons of water in Lake Conemaugh, 14 miles upstream from Johnstown. It was owned by the South Fork Fishing and Hunting Club — a private resort whose members included Andrew Carnegie, Henry Clay Frick, and Andrew Mellon. Maintenance had been deferred. The spillway had been filled in to allow carriages to cross. Fish screens prevented the overflow pipes from clearing. When three days of record rainfall began on May 28, 1889, the end had already been written.

At 3:10 PM on May 31, 1889, the South Fork Dam failed catastrophically. The 72-foot tall earthen dam collapsed and Lake Conemaugh — 2 miles long, 1 mile wide, and 60 feet deep — drained entirely in 36 minutes. A wall of water, trees, railroad cars, houses, and debris 30 to 40 feet high moved down the Conemaugh Valley at 40 miles per hour. It carried the weight of a naval fleet.

The flood wave hit Johnstown at 4:07 PM. Downtown vanished in minutes. The wave compressed the city — whole neighborhoods driven toward the Stone Bridge and piled against it. When debris at the bridge caught fire that night, hundreds who had survived the wave burned in the wreck. In the darkness after, people stood on rooftops, on drifting piles of wood, calling out names. No answer came for 2,208 of them.

Clara Barton arrived on June 5 with 50 Red Cross volunteers. She stayed five months. Eighteen foreign nations sent aid. Within weeks, relief trains were arriving daily. Within two years, Johnstown had rebuilt. The Cambria Iron Mills — birthplace of American steel rail, employer of 12,000 — were producing steel again within months. No legal accountability was ever established against the South Fork Fishing and Hunting Club. Andrew Carnegie donated a new library.