1977 Johnstown Flood

Today marks the 43rd anniversary of the 1977 Johnstown Flood. Flash flooding and dam failure contributed to the death and destruction involved in the third of Johnstown’s great floods.

Nature’s Build Up

Rain began pounding on Johnstown and surrounding areas during the night of July 19th. Thunderstorms are nothing new for this area and many were not initially concerned about the rain. However, the line of thunderstorms stalled.

Staying steadfast over our corner of Western PA, the storms dumped nearly 12 inches of rain in as little as 10 hours. The small streams of Solomon’s Run, Peggy’s Run and others carved new channels and smashed through road ways, houses and factories.

The National Weather Service later estimated that this amount of rain occurs less than once every 1000 years. The down pour wasn’t the only factor in the floods devastation though.

Contributing Factors

The failure of the dams and flooding of the city came as quite a surprise. After the 1936 flood, the U.S. Army Corps of Engineers began work on flood control measures. They finished what was then the nation’s largest flood-control system in 1943.

One of these measures involved deepening and realigning the channels of the Stonycreek and Little Connemaugh. They also added nine miles of side slopes made of concrete.

Once their Flood Protection Measures were completed,the city was promoted as a “flood free city”. Sadly, they were wrong.

Six of the areas dams burst under the strain of the incoming rain. Laurel Run Dam was the largest. It was a ten year old earthen dam holding back around 100 million gallons of water. This dam had been well maintained. Laurel Run also had a 42 foot high spillway. These factors should have helped prevent failure.

When Laurel Run Dam failed it destroyed Tanneryville and killed around 40 people. Another five dams failed contributing another 28 million gallons of water.

The dams were regularly inspected and had no defects at the time of the flood. They should have been secure. However, humans always underestimate the power of Mother Nature. The swift falling water rose quickly and caused instability and lead to failure.

1977 Johnstown Flood: Aftermath

The flood caused around $300 million in damages and killed 85 people. Hundreds were now homeless. They were forced to seek shelter in churches, schools and even dormitories at the University of Pittsburgh at Johnstown.

President Jimmy Carter declared a federal disaster area for Cambria, Somerset, Indiana, Bedford, Westmoreland, Clearfield, Jefferson and Blair on July 21st. The National Guard deployed to help rescue and clean up. Several non-profits, including the Red Cross, came to lend help. The Inclined Plane was used to help evacuate people and transport supplies and rescuers back down.

This flood decimated Johnstown’s fragile economy. Despite the effort to rebuild, the city failed to flourish. Between 1970 and 1980 the population dropped by 19.4%. The 1977 Flood had a lot to do with this decrease. Some businesses destroyed or damaged never rebuilt. People moved out to avoid another flood.

Many people alive today remember the 1977 flood. A memorial to the victims is located in Central Park. Check out JAHA’s page to see more photos and access oral histories of survivors.