On May 31, 1889, after days of heavy rain over western Pennsylvania, the South Fork Dam gave way shortly after 3 p.m. The earthen dam, fourteen miles above Johnstown, held back Lake Conemaugh; when it failed, some twenty million tons of water poured down the Conemaugh Valley and reached Johnstown in under an hour, in places a churning wall of water and wreckage seventy feet high. When it had passed, 2,209 people were dead — the toll kept by the National Park Service — and much of the city was destroyed. Debris piled against the railroad’s stone bridge caught fire and burned for days.
The dam had been built by the Commonwealth of Pennsylvania for a canal reservoir and later abandoned. The South Fork Fishing and Hunting Club — a private summer retreat whose members included Pittsburgh industrialists Andrew Carnegie and Henry Clay Frick — took it over and rebuilt it to deepen its fishing lake: the crest was lowered by some three feet, the dam’s five cast-iron discharge pipes were removed and never replaced, and the spillway was left obstructed by debris and fish screens. Engineers who inspected the dam warned that it was unsafe. The warnings went unheeded.
The American Society of Civil Engineers appointed a committee under James B. Francis to investigate; its report, published in the Society’s Transactions in 1891, documented the club’s alterations in detail — though its conclusion, that the storm would probably have overwhelmed the dam even as originally built, has been challenged by modern engineering re-analysis. In the courtroom the survivors fared worse than in the engineers’ report: their lawsuits failed, the flood was treated in law as an act of God, and no liability was ever established against the club. Individual members gave money to the relief effort, but the club itself never paid damages.
The relief operation became a landmark in its own right. Clara Barton reached Johnstown on June 5, 1889, and the young American Red Cross stayed for five months — its first great peacetime disaster relief effort. The remains of the dam are preserved today by the National Park Service at the Johnstown Flood National Memorial.