Johnstown flood of 1977

The Johnstown flood of 1977, also known as the second great flood of Johnstown and the Johnstown disaster, was a major flood which began on the night of July 19, 1977, when heavy rainfall caused widespread flash flooding in Cambria County, Pennsylvania, including the city of Johnstown and the Conemaugh Valley.

Johnstown flood of 1977
Panoramic view of the flood.
DateJuly 19, 1977 to July 20, 1977
LocationJohnstown, Pennsylvania area
Deaths84
Property damageUS$340 million (Johnstown: $137 million; surrounding areas: $213 million)[1]

After the Johnstown flood of 1936, the U.S. Army Corps of Engineers undertook a study with the aim of redesigning Johnstown's infrastructure to permanently remove any future threat of serious flooding. Work began in August 1938 with extensive dredging and flood control measures. On November 27, 1943, Colonel Gilbert Van B. Wilkes, Chief of the Army Corps of Engineers, Pittsburgh District, told a Johnstown audience the flood problems had been effectively solved. The city's residents began to feel secure that any flooding issues had been resolved and even promoted the area as "flood free" for many years. However, the Corps of Engineers had designed the flood control measures for protection against a standard project flood; protection to the 500-year level was not economically viable. In 1974, the Corps issued a report titled "The Potential for Future Flooding in the Johnstown Area", which failed to grasp the attentions of town leaders and the people of Johnstown.

On July 19, 1977, a deluge of rain hit the area around Johnstown during the night. Nearly 12 inches (300 mm) of rain fell in 24 hours when a thunderstorm stalled over the area, and six dams in the area over-topped and failed. The largest dam to fail was the Laurel Run Dam, releasing over 101 million gallons (382,000 m3) of water that poured through the village of Tanneryville, killing 41 people. The combination of the other five dams[2] released another 27 million gallons (100,000 m3), not counting the water from rains. Well over 128 million gallons (485,000 m3) of water from the dams alone poured down the valley, and by dawn Johnstown was inundated with six feet of water. The channel improvements were designed to carry 81,500 cubic feet (2,300 m3) per second, but the 1977 flood discharge was measured as 115,000 feet (3,250 m3) per second.[3] 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."[4]

History
Main article: Johnstown, Pennsylvania

Johnstown

A Swiss immigrant named Joseph Schantz started farming at the confluence of the Little Conemaugh River and the Stoneycreek River around 1794. He laid out plans for a town and chose the name Conemaugh after a Native American village that occupied the same site. The plan accounted for the fact that a new county named Cambria would be taken from Somerset County but lobbying for the new town to be the county seat failed as Ebensburg was chosen. The town was situated within the Conemaugh River sub-basin (Ohio River Basin)[5] and was prone to flooding.

Surrounding area

After the flood of 1889, no significant flood measures were undertaken. In 1936, Congress was looking at flood control bills. During this time heavy snow run-off and three days of continuous rainfall caused the Saint Patrick's Day flood of 1936. On April 27, 1937, Congress passed sweeping flood control legislation and in 1938 work began. On November 27, 1943, the Johnstown Channel Improvement Project was completed, with 9.1 miles (14.6 km) of improvements that included the Conemaugh River, Stony Creek, and the Little Conemaugh River.[6]

Dam failures
Laurel Run dam failure
Further information: Laurel Run Dam

The Laurel Run Dam on Laurel Run was an old earthen dam owned by the Bethlehem Steel company and sold to the Johnstown Water Company. This dam had a 42.5-foot (13 m) high spillway, and when it failed about 101 million gallons (382,000 m3) of water was released. After the dam failed, water rushed through the Tanneryville neighborhood. The Sandy Run Dam, a 28-foot (8.5 m) high, a 63-year old earthen dam with a spillway owned by the Highland Water and Sewer Authority, released a little more than 18 million gallons of water. When the dam failed the flood waters entered the Conemaugh between St. Michael and South Fork at Ehrenfeld. The Salix Water Dam on Otto Run, owned by the Adams Township Water Authority, was a 25-foot (7.6 m) earthen dam that held 2 million gallons (7,600 m3) of water. When the dam failed, the flood waters ran into the South Fork Little Conemaugh River which joins the Conemaugh River in Sidman. The Cambria Slope Mine #33, on Sanders Run, had a spillway height of 32 feet (9.8 m) and was leased by the Bethlehem Mines Corporation, and held 7 million gallons (26,500 m3) of water. Sanders Run flows adjacent to and joins Howells Run, skirting Ebensburg draining into City Reservoir. The dam was a total failure.[7] An Unnamed dam on Peggy's Run, Franklin Borough, was leased to Bethlehem Mines Corporation. The dam was situated outside Franklin and the water shed drained towards East Conemaugh and the Conemaugh River. The dam failure released an unknown amount of water. An unnamed impoundment dam, holding 1000 gallons (4 m3) of reserve water for Bethlehem Mines Corporation, also failed.

The victims of the 1977 flooding were from Old Conemaugh Borough (2), Hornerstown (4), Walnut Grove (3), West End (1), Dale Borough (10), Seward (7), Strongstown (1), Tanneryville (39 including those still missing), Windber, (2), Summerhill (1), Dilltown (1), Dunlo (3), Mineral Point (2), Richland (6), and Scalp Level (2)[8][9]


Effects on the Economy

Johnstown, a once booming steel city was significantly impacted by the aftermath of flood. In a city that relied so heavily on the steel industry in its economy, the effects of this disaster would be felt for some years to come. The Bethlehem Steel Company had roots into the industry within Johnstown. As the company continued to face a decline in profits in the years after the flood, they looked to Johnstown for solutions. With continuous cutbacks, Johnstown had ranked as the area with the least profit made. Over 2,300 steel jobs were terminated in Johnstown as a part of cutbacks by CEO of Bethlehem Steel, Donald Trautlein. He invested no more money into the city as he did not see any more profit to be made.[10]

See also

References
  1. NOAA:1977 damages, Retrieved 2016-01-01
  2. Dam safety:Number of failures in 1977, Retrieved 2016-01-01
  3. NOAA flood discharge, pg. 9, Retrieved 2016-01-01
  4. "Three Floods Later, Johnstown is Still Standing". AccuWeather. Retrieved 4 January 2016.
  5. Ohio River Basin reference, Retrieved 2016-01-01
  6. 1977 Johnstown area flood control, pg. 7-9, Retrieved 2016-01-01
  7. Sanders Run Google map reference, Retrieved 2015-01-01
  8. Johnstown victims remembered, Retrieved 2016-01-01
  9. 1977 failure of Laurel Run dam, pg. 14-16, Retrieved 2016-01-01
  10. Farabaugh (2019). "Water and Steel: The 1977 Johnstown Flood and the Bethlehem Steel Corporation". Pennsylvania History: A Journal of Mid-Atlantic Studies. 86 (3): 383. doi:10.5325/pennhistory.86.3.0383. ISSN 0031-4528. S2CID 197739210.

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