The Avalanche That Killed Thousands Because the Government Failed To Heed Warnings

Mount Huascarán rises 22,000 feet above sea level in the Andes Mountains. Beneath it laid many small Peruvian communities, the inhabitants of which farmed in the Rio Santa Valley. On the evening of July 10, 1962, just as most of the region’s people gathered in their homes for dinner, the edge of a giant glacier suddenly broke apart and thundered down the mountain. The block of ice was the size of two skyscrapers and weighed approximately 6 million tons. Because avalanches were common in the area, residents knew that there was normally a 20-30 minute gap between the sound of the ice cracking off and an avalanche, which gave people time to make it to higher ground. However, this time, the avalanche traveled 9½ miles in only 7 minutes, wiping out several communities. The towns of Ranrahirca and Huarascucho were buried under 40 feet of ice, mud, trees, boulders and other debris. Only a handful of people in each town survived. The avalanche finally ended at the Santa River, where it stopped the water flow, flooding in nearby areas. The disturbing part of the incident was that it didn’t have to result in massive deaths. That’s because in January 1962, American scientists David Bernays and Charles Sawyer had reported seeing a massive vertical slab of rock being undermined by a glacier on Mount Huascarán Norte, which threatened to fall and cause the obliteration of Yungay. When this was reported in the Expreso newspaper, the government ordered them to retract or face prison. Meanwhile, Sawyer and Bernays were forced to flee the country. Just 7 months later, their prediction came true. 
A chunk of ice estimated to have weighed 700 tons was swept along and came to rest near Ranrahirca.