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Water, Water Everywhere: The Johnstown Flood
Background Information for Teachers

Johnstown Flood
At approximately 3:00 p.m. on May 31, 1889, the South Fork Dam gave way, unleashing 20 million tons of water into the valley below. Johnstown and the surrounding communities lay in the path of the rushing waters. In its effect, the Johnstown Flood became one of the worst natural disasters experienced in this country.
It had been raining heavily the two days preceding the flood. Water levels had risen steadily; many people had already moved their belongings to the second floors of their homes as the rising water gradually flooded the valley. Flooding was not an uncommon occurrence in this region of southwestern Pennsylvania, and there was little cause to believe this flooding would prove much worse than others.
Roughly 14 miles up and above the valley stood the South Fork Dam. The Dam was built originally by the state of Pennsylvania in 1838 to serve as a reservoir basin for the Pennsylvania Canal. By the time of the canal's completion in 1853 the railroad had eclipsed the canal system as a method of transportation, and the state sold the dam to the Pennsylvania Railroad. Standing 72 feet high and 900 feet wide, the impressive dam held back the force of the Conemaugh River, creating a massive reservoir out a small natural lake.
Having little use for the outdated dam, the Pennsylvania Railroad subsequently sold the property to John Reilly, a congressman from Altoona. Hoping to sell the property for a profit, Reilly instead found little interest. He sold the property in 1879 to the South Fork Fishing and Hunting Club. The club's membership consisted largely of prominent and wealthy Pittsburgh businessmen, including the industrialists Andrew Carnegie and Henry Clay Frick. Retreating to the cottages and clubhouse along the lake for sporting games, the group regarded the property as a welcome and close retreat from city life.
At the time the club purchased the property, there was some indication that the dam was in need of repairs. The dam had already failed once under Pennsylvania Railroad ownership during the dry summer of 1862; repairs and improvements to the dam began in 1879. The dam would hold for 10 years, finally failing during one of the worst storms of the 1800s. At that point, the dam contained a lake which stretched over two miles long, a mile wide, and had a depth of 60 feet at the dam itself.
On the morning of May 31, 1889, after a night of heavy rainfall, the president of the club, Elias Unger, noticed a marked increase in the water level of the lake. It had risen over two feet overnight. With the waters continuing to rise, Unger ordered last-ditch efforts to try to prevent the lake from overflowing and dispatched a member to the nearest town to telegraph a warning to Johnstown. Immigrant laborers toiled through most of the day, first attempting to increase the height of the dam, then digging spillways and removing barriers in the overflows meant to contain the fish. Their effort was to no avail, and around 3 p.m., the waters first spilled over the dam. Then the dam gave way completely.
When it gave way, the dam unleashed some 20 million tons of water. Fourteen miles down the valley, Johnstown and the surrounding communities lay in the path of a tidal wave of water racing at an average speed of 40 miles an hour. In minutes, the wave, now heavy with accumulated debris and bodies, 35 feet high at its crest and with the force of Niagara Falls, hit Johnstown. For most, the only warning was a thunderous rumble before the water hit.
The devastation was unimaginable. People clung to roofs, debris, and the few buildings that remained standing, as others were carried down the valley to their deaths. At the Pennsylvania Railroad's stone bridge, debris from the water created a jam. Forty feet high and 30 acres across, the pile against the bridge quickly caught fire. The known death toll from the flood waters was 2,209, and four square acres of downtown Johnstown were completely leveled. Before the flood, the population of Johnstown and surrounding communities was only 30,000.
The flood became the immediate news event of the decade. Even as the waters were receding, hundreds of journalists arrived to document the disaster for the world, capturing their reader's attention with their wrenching stories, photographs, and illustrations. The American public responded and money, clothing, and food rapidly came in. Doctors, nurses, and Clara Barton and the American Red Cross arrived to provide medical assistance and emergency shelter and supplies. The Johnstown Flood was the first major disaster served by the recently formed Red Cross. Over 2,000 bodies were gradually prepared for funeral, more than 700 of whom were unidentified victims.
In the following weeks and months, the city gradually rebuilt. The Cambria Iron Works, Johnstown's major industry and employer, reopened on June 6, just days after the devastating event. With rebuilding also came questions. Although suits were filed against the South Fork Fishing and Hunting Club, no legal actions or compensation resulted. Several of the club members, including Carnegie and Frick, supported the relief and rebuilding efforts with large donations.
Although one of the worst natural disasters ever seen, Johnstown did not gain protection from flooding in the future. In 1936 another severe flood, though not of the magnitude of 1889, finally provoked action and resulted in the passage of the Flood Control Act of 1936. By 1943, the Johnstown Local Flood Protection Program, a series of channel improvements, dikes, and concrete walls, was completed. Designed to protect Johnstown from ever experiencing floods of the level of 1889 and 1936, the JLFPP protected the city from further major flooding until 1977. Although brutal and resulting in a seven-county disaster area, the effects of this flood were not as devastating as the flood of 1889. The JLFPP project mitigated the effects, reducing the flood level an estimated 11 feet.

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