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This Russian City Has Been Swallowed By Sinkholes

Berezniki is a Russian city located in the Ural mountains. It is slowly making its way into the earth. However, a more apt definition would be that it is slowly sinking into the earth. The city housed 150,000 individuals and was constructed on top of a potash mine. This was standard practice during Soviet times. However, after about a hundred years of extraction, the deep voids have been left under the city. The ceilings of the giant caverns under Berezniki are supported only by walls and pillars of soluble salt. Back in 2006, a freshwater spring started flowing into the mine about 720-1,500 ft under the surface, and you can guess what happened; the salt dissolved, thus taking away the support under the city of Berezniki.

A large part of the residential districts and enterprises of Berezniki have been affected by sinkholes. These sinkholes are large in number with the biggest one of them named ‘The Grandfather’. The Grandfather is about four hundred meters across and has a depth of over two hundred meters. It even poses a threat to the sole rail line that goes into and out of the potash mines. Berezniki is responsible for producing ten per cent of the world’s potash, and the mines are the biggest employer of the city. Closure of the mines will have a devastating effect on the local economy.

A combination of high-tech gadgets including seismic sensors, video surveillance systems, regular surveys, and even satellite monitoring systems are in place for recording the changes in altitude of roofs, streets, and sidewalks in Berezniki for predicting the formation of sinkholes. However, engineers have assured that the era of sinkhole formation is over since much of the mine is flooded now. Nonetheless, the federal officials and company executives are debating if they should relocate the complete city to Kama River’s opposite bank where the bedrock is solid.