Today In History, 1889: The Johnstown Flood: On May 30 a huge storm rolled into Johnstown, PA (About 60 miles east of Pittsburgh). The next morning (Today) there was some minor flooding. . . But the real problem laid 15 miles above sea level, in the Allegheny Mountains. . .

A few years earlier a cooperation called the "South Fork Fishing and Hunting Club" built a mountain retreat on a 450 acre man-made lake. To create the lake the club had patched up an old dam. The club was frequented by the Pittsburgh elite, including Andrew Carnegie. . .

Despite multiple warnings by local engineers the club did nothing to strengthen the dam. . . About 3:15 PM on May 31, the day after the storm, the dam broke - Releasing 20 million tons of water. The lake emptied in 40 minutes, doing so with the force of Niagara Falls. . .

The water flowed down the mountain at a speed of 40 MPH, destroying anything in its path. The surge crashed into Johnstown just after 4 PM. A tsunami rushed through the city, taking people, livestock and 1,500 homes/buildings with it. It took 10 minutes to flatten the city. . .

The official death toll of the Johnstown flood is 2,209. Makeshift morgues were set up throughout town, but hundreds were never found, and a third of the bodies could not be identified. . .

Relief efforts from around the country began to sweep in. Including from the newly established American Red Cross. Its founder, Clara Barton, would remain in Johnstown for 5 months. . The South Fork Fishing and Hunting Club was never held responsible

The great American Historian, David McCullough, has a great book on this subject