Johnstown Flood National Memorial

The South Fork Dam was an earthenwork dam forming Lake Conemaugh (formerly Western Reservoir, also known as the Old Reservoir and Three Mile Dam, a misnomer), an artificial body of water near South Fork, Pennsylvania, United States. On May 31, 1889, the South Fork Dam failed catastrophically and 20 million tons of water from Lake Conemaugh burst through and raced 14 miles (23 km) downstream, causing the Johnstown Flood.

The Johnstown Flood, sometimes referred to locally as Great Flood of 1889, occurred on Friday, May 31, 1889, after the catastrophic failure of the South Fork Dam, located on the south fork of the Little Conemaugh River, 14 miles (23 km) upstream of the town of Johnstown, Pennsylvania, United States. The dam ruptured after several days of extremely heavy rainfall, releasing 14.55 million cubic meters of water. With a volumetric flow rate that temporarily equaled the average flow rate of the Mississippi River, the flood killed 2,208 people and accounted for US$17,000,000 (equivalent to about $550,000,000 in 2022) in damage. The American Red Cross, led by Clara Barton and with fifty volunteers, undertook a major disaster relief effort. Support for victims came from all over the U.S. and eighteen foreign countries. After the flood, survivors suffered a series of legal defeats in their attempts to recover damages from the dam's owners. This led to American law changing from a fault-based regime to one of strict liability.

The South Fork Fishing and Hunting Club was a Pennsylvania corporation that operated an exclusive and secretive retreat at a mountain lake near South Fork, Pennsylvania, for more than 50 extremely wealthy men and their families. The club owned the South Fork Dam, which failed on May 31, 1889, causing the Johnstown Flood that killed more than 2,200 people. The dam's failure released an estimated 14.3 million tons of water from Lake Conemaugh, wreaking devastation along the valley of South Fork Creek and the Little Conemaugh River as it flowed about a dozen miles downstream to Johnstown, Pennsylvania. It was the worst disaster in U.S. history at the time. Relief efforts were among the first major actions of Clara Barton and her newly organized American Red Cross. The club had neglected maintenance on the dam and performed some ill-advised alterations. Despite some years of claims and litigation, the club and its members were never found to be liable for monetary damages. The corporation was disbanded in 1904, and its real estate were sold by the local sheriff at public auction, largely to satisfy a mortgage on the large clubhouse.

The Johnstown flood of 1977 was a major flood which began on the night of July 19, 1977, when heavy rainfall caused widespread flash flooding in Cambria County, Pennsylvania, United States, including the city of Johnstown and the Conemaugh Valley. On July 19, a deluge of rain hit the Johnstown area during the night. Nearly 12 inches (300 millimetres) of rain fell in 24 hours when a thunderstorm stalled over the region, and six dams in the area over-topped and failed. The largest dam to fail was the Laurel Run Dam, releasing over 101 million U.S. gallons (380,000 cubic meters) of water that poured through the village of Tanneryville, killing 41 people. The combination of the other five dams released another 27 million US gallons (100,000 m3), not counting the water from rains. Well over 128 million US gallons (480,000 m3) of water from the dams alone poured down the valley, and by dawn Johnstown was inundated with six feet (1.8 m) of water. The channel improvements were designed to carry 81,500 cu ft/s (2,310 m3/s), but the 1977 flood discharge was measured as 115,000 cu ft/s (3,300 m3/s). Ron Shawley, executive director of Laurel Highland's Historical Village, returned to Johnstown on July 20 and stated "It was like somebody dropped an atomic bomb on Johnstown" and that "I questioned what kind of force it would take to do that."

St. Michael is an unincorporated community and census-designated place in Cambria County, Pennsylvania, United States. Its ZIP code is 15951. It was formerly part of the St. Michael-Sidman census-designated place in Cambria County, before splitting into two separate CDPs for the 2010 census. As of the 2010 census the population of St. Michael was 408.St. Michael is located in southeastern Cambria County in the valley of the South Fork of the Little Conemaugh River, less than a mile southeast of U.S. Route 219, a four-lane highway which leads 12 miles (19 km) north to Ebensburg, the county seat, and 11 miles (18 km) southwest (via Pennsylvania Route 56) to Johnstown. The community of Sidman is one mile southeast of St. Michael, also in the valley of the South Fork.

South Fork is a borough in Cambria County, Pennsylvania, United States. It is part of the Johnstown, Pennsylvania Metropolitan Statistical Area. The population was 928 at the 2010 census, down from 1,138 at the 2000 census.

St. Michael-Sidman was a census-designated place (CDP) in Cambria County, Pennsylvania, United States. The population was 973 at the 2000 census. For the 2010 census, the area was split into two CDPs, St. Michael and Sidman.

Ehrenfeld is a borough in Cambria County, Pennsylvania, United States. It is part of the Johnstown, Pennsylvania Metropolitan Statistical Area. The population was 228 at the 2010 census.

Forest Hills High School, located in Sidman, Pennsylvania, is a small, rural, public high school. In 2014, enrollment was reported as 454 pupils in 10th through 12th grades.The principal is Rebecca Roberts. It once was composed of 4 high schools before their unification to Forest Hills in 1966. The 4 high schools were: Triangle Area, Adams-Summerhill, South Fork-Croyle, and Beaverdale-Wilmore. The district encompasses 3 townships: Adams, Croyle, and Summerhill. Forest Hills High School students may choose to attend Greater Johnstown Career and Technology Center for training in the construction and mechanical trades as well as other careers. The Appalachia Intermediate Unit IU8 provides the School with a wide variety of services like specialized education for disabled students and hearing, background checks for employees, state mandated recognizing and reporting child abuse training, speech and visual disability services and professional development for staff and faculty.

Summerhill is a borough in Cambria County, Pennsylvania, United States. The population was 490 at the 2010 census.

Sidman is an unincorporated community and census-designated place in Cambria County, Pennsylvania, United States. Its ZIP code is 15955. It was part of the St. Michael-Sidman census-designated place, before it was split into two separate CDPs during the 2010 census. The population of Sidman as of the 2010 census was 431.

Croyle Township is a township in Cambria County, Pennsylvania, United States. It is part of the Johnstown, Pennsylvania Metropolitan Statistical Area. The population was 2,339 at the 2010 census.