The Johnstown Flood killed 2,209 people, among them 99 whole families and 396 children.
The Johnstown Flood was the direct result of negligence on the park of the owners of the South Fork Fishing and Hunting Club, who owned the South Fork Dam and Lake Conemaugh. The members of the club made several key changes to the South Fork Dam, which are believed to have weakened it structurally. These changes included installing a fish screen in the spillway, which trapped debris, and lowering the top of the dam. The club then failed to properly maintain the South Fork Dam, which sprang frequent leaks in the years between 1881 and its collapse on the afternoon of 31 May 1889.
Public outcry in the wake of the Johnstown Flood led to the adoption of the British common law precedent, Rylands vs. Fletcher, in the United States, and ushered in the era of strict liability in the American legal system.