Johnstown Flood (1889): The South Fork Dam Disaster

The Johnstown Flood was one of the deadliest disasters in American history. On the afternoon of 31 May 1889 the South Fork Dam, an earthen dam about 14 miles (23 km) above Johnstown, Pennsylvania, collapsed after days of heavy rain. The water of Lake Conemaugh swept down the narrow valley and destroyed much of the town, killing 2,209 people and raising lasting questions about the responsibility of the wealthy men who owned the dam.

Background: an old dam and a private lake

Johnstown was a busy steel town in western Pennsylvania, built where the Little Conemaugh and Stony Creek rivers meet to form the Conemaugh River. In 1889 the town and its surrounding boroughs had around 30,000 people, many of them working for the Cambria Iron Company. The valley was steep and narrow, and spring floods were common.

The South Fork Dam had been built by the Commonwealth of Pennsylvania between 1838 and 1853 to supply a reservoir for the state canal system. When railways made the canal obsolete, the dam was sold in 1857 to the Pennsylvania Railroad and later passed to private owners. It was neglected, and a partial break occurred in 1862 when the lake was low.

In 1879 the Pittsburgh businessman Benjamin Ruff bought the property for the newly organised South Fork Fishing and Hunting Club. Its members were wealthy men from Pittsburgh, including Henry Clay Frick, Andrew Carnegie, Andrew Mellon and Philander Knox. The club rebuilt the dam and refilled Lake Conemaugh, which became a private resort with cottages, a clubhouse and boats.

Problems with the dam

The repairs were poorly done. The breach was filled with earth, rock, brush and even hay rather than being properly engineered. The crest of the dam was lowered, by perhaps two to three feet, so that a road could run across its top wide enough for carriages. This reduced the height between the water and the top of the dam.

The discharge pipes at the base, which had allowed the lake to be drained in an emergency, had been removed and not replaced. A screen was placed across the spillway to keep the club’s stocked fish from escaping, and debris could collect against it. The dam also sagged slightly in the middle, the very place where water would first flow over the top.

People downstream worried about the dam. Daniel Johnson Morrell, head of the Cambria Iron Company, had it inspected in 1880 by an engineer, John Fulton, who warned of leaks and the lack of discharge pipes. Morrell offered help with repairs, and later joined the club, but no major work followed. Rumours of a dam failure had circulated so often that many residents had stopped taking them seriously.

What happened on 31 May 1889

Late in May 1889 a heavy storm moved across the region. On 30 and 31 May between about 6 and 10 inches of rain fell in the area within roughly a day, among the heaviest rainfalls recorded there. Johnstown itself was already flooded by the rivers in the morning, with water several feet deep in the streets.

At the dam, the club’s president, Elias J. Unger, and the young resident engineer, John G. Parke Jr., tried to save it. Workers struggled to cut a new spillway and to raise the crest with earth, but the lake rose too fast. Parke rode to the village of South Fork to send warnings by telegraph. Some messages reached Johnstown, but they were not treated as an emergency.

At about 3:10 pm the water flowed over the top and the dam collapsed. An estimated 20 million tons of water, the contents of a lake roughly two miles long, poured into the valley. The lake emptied in around 40 minutes.

The flood wave

The wave did not move as a smooth wall of water. It carried trees, houses, rail cars, barbed wire from a wire works and thousands of tons of debris, which repeatedly jammed in narrow places and then broke loose. It swept away the village of South Fork, the town of Mineral Point and part of East Conemaugh, where locomotives in the rail yard were tossed aside.

The wave reached Johnstown at about 4:07 pm, roughly an hour after the dam failed. Witnesses described a rolling mass of wreckage that at its front reached heights often estimated at 30 to 40 feet. In about ten minutes, much of the town was destroyed.

Downstream, the debris piled up against the massive stone railway bridge of the Pennsylvania Railroad. The jam covered around 30 acres and trapped hundreds of people. That evening it caught fire, probably from overturned stoves and lamps, and the fire burned for days. Around 80 people are believed to have died in it.

Key people

Elias J. Unger was the club’s president and was at the lake when the crisis began. He organised the last efforts to save the dam and later testified about its condition.

John G. Parke Jr. was a young engineer working for the club. His ride to South Fork to warn the valley became one of the best-known episodes of the day.

Clara Barton, founder of the American Red Cross, arrived in early June with volunteers and supplies. She stayed about five months, building temporary housing and running distribution centres. Johnstown was the organisation’s first large peacetime disaster relief operation and made its reputation in the United States.

Henry Clay Frick and Andrew Carnegie were among the club’s best-known members. Neither was at the lake that day, and both contributed to the relief fund. Carnegie later paid for a new public library in Johnstown.

Liability and the debate over the club

Public anger focused on the South Fork Fishing and Hunting Club. Newspapers denounced the rich men who had kept a pleasure lake above a working town, and the disaster became a symbol of the gulf between industrialists and workers in the Gilded Age.

Survivors filed lawsuits against the club and individual members, but none succeeded. The club had few assets, and courts tended to treat the flood as an act of God or held that negligence by particular people could not be proved. No one was ever held legally responsible.

The case influenced American law. In the following decades, more state courts adopted the principle, drawn from the English case Rylands v. Fletcher (1868), that the owner of a dangerous structure such as a reservoir can be liable for damage it causes even without proof of negligence. Historians differ on how directly Johnstown caused this shift, but it was widely cited in the debate.

Consequences

The human toll was enormous. The official count of 2,209 dead included 396 children and 99 entire families. Many bodies were found months later, some far downstream, and 777 unidentified victims were buried together in the Unknown Plot at Grandview Cemetery.

Property losses were estimated at about $17 million at the time. More than 1,600 homes were destroyed. Donations of money, food and clothing came from across the United States and from abroad, including Europe, in one of the first great national relief efforts of the modern era.

Johnstown was rebuilt, and the Cambria Iron Company resumed production. The town suffered major floods again in 1936 and 1977, but none as deadly as that of 1889.

Myths and facts

Myth: The flood was simply the result of a freak storm. The rainfall was exceptional, but engineers who examined the dam afterwards pointed to the lowered crest, missing discharge pipes and obstructed spillway. Modern hydraulic studies suggest that the original design might still have failed under such rain, but the alterations made a failure more likely and gave less time.

Myth: Nobody had any warning. Telegraph warnings were sent from South Fork that afternoon, and some reached Johnstown. They were not acted upon in time, partly because similar alarms in earlier years had proved false and because the town was already flooded.

Myth: The wave was a wall of clear water. Survivors described a churning mass of debris, often with a mist or dark cloud in front of it. The wreckage it carried, not only the water, caused much of the destruction.

By the numbers

Timeline

• 1838-1853: The Commonwealth of Pennsylvania builds the South Fork Dam for the canal system.
• 1862: A partial break occurs while the reservoir is low.
• 1879-1881: The South Fork Fishing and Hunting Club acquires and repairs the dam and refills Lake Conemaugh.
• 1880: Engineer John Fulton inspects the dam for the Cambria Iron Company and warns of defects.
• 1889, 30-31 May: Torrential rain falls over the Conemaugh Valley.
• 1889, 31 May, about 3:10 pm: The South Fork Dam collapses.
• 1889, 31 May, about 4:07 pm: The flood wave reaches Johnstown; the debris at the Stone Bridge catches fire that evening.
• 1889, June: Clara Barton and the American Red Cross arrive and begin a five-month relief operation.
• 1964: The Johnstown Flood National Memorial is established at the site of the dam.

Legacy

The flood remains a defining moment in Johnstown’s history and in American memory of the Gilded Age. The Johnstown Flood National Memorial preserves the remains of the dam and the clubhouse area, and the Johnstown Flood Museum tells the story in the town.

David McCullough’s book The Johnstown Flood (1968) brought the disaster to a wide modern audience. Engineers still cite it in discussions of dam safety, alongside later failures such as the St. Francis Dam disaster and the Banqiao Dam failure. Within a few years the United States would face an even deadlier flood in the Galveston hurricane of 1900.

Why it matters

The Johnstown Flood showed how a neglected structure owned for private pleasure could destroy a working community below it. It established the American Red Cross as a disaster relief organisation, shaped debates on legal liability and became a lasting lesson in the importance of dam safety.