Terrifying ‘River of Ice’ Collapse Killed Hundreds

The Kolka Glacier flood was one of the most terrifying disasters to occur in Russia, in 2002. The collapse of the glacier, also described as a river of ice, claimed hundreds of lives.

According to the National Aeronautics and Space Administration (NASA), the disaster took place in the Caucasus Mountains in the Republic of North Ossetia, southern Russia. At around 8pm local time on 20 September 2002, a mass of rock and hanging glacier on the northern slope of Mount Dzhimarai-Khokh broke away and fell on the Kolka Glacier below.

The impact was immense. It destroyed the Kolka Glacier and triggered a huge avalanche of more than 100 million cubic metres of ice, snow and rock into the Genaldon River valley.

The avalanche travelled 18 kilometres at speeds of up to 180 kilometres per hour. It swept through the Karmadon Depression, damaging and burying the village of Nizhniy Karmadon and several other settlements.

The debris became blocked in the narrow Gates of Karmadon, forming a natural dam up to 130 metres high and creating temporary freshwater lakes.

125 dead

At least 125 people were reported dead or missing, buried beneath the ice and avalanche debris. Because the layers of ice and rock were so thick, only 20 bodies were recovered during the rescue operation.

Official reports identified the immediate trigger as the collapse of rock and hanging glacier from Mount Dzhimarai-Khokh, which struck the Kolka Glacier. Researchers identified several contributing factors.

One was the disaster site’s proximity to Mount Kazbek, a dormant volcano. Geothermal activity and sulphur gas emissions (fumaroles) were thought to have raised temperatures beneath the glacier, melting the lower ice layer and allowing large pockets of water to accumulate.

In addition, two minor earthquakes in the months before the disaster were thought to have weakened the attachment of the hanging glacier to the mountainside.

Researchers classified the event as a collapse of exceptional, planetary scale. It was not merely a seasonal glacier surge.