Mudslide Danger on Mont Blanc: Subglacial Lake Threatens Alpine Community
Engineers are beginning a delicate operation to drain a huge lake under a glacier on Mont Blanc. If it bursts, it could trigger a giant mudslide that would threaten thousands of people in the valley below.
Avalanches. Falling rocks. Frostbite. Such are the dangers on might normally associate with the Alps.
Engineers begin work on draining the subglacial lake Wednesday. They are planning to drill a hole through the ice to allow the water to be pumped away. The operation is expected to cost around 2 million ($2.5 million).
The lake, which was discovered last month under the Tete-Rousse glacier during a routine inspection using magnetic resonance imaging, is thought to contain around 65,000 cubic meters (2.3 million cubic feet) of water -- the equivalent of 26 Olympic-sized swimming pools. Should it be released, the valley could flood in just 15 minutes. The water could create a deadly mudslide "six to eight times bigger than the original volume of water," according to scientists quoted by the Daily Telegraph.
Around 3,000 people live in the valley and it is popular with tourists. Local authorities have prepared an evacuation plan and an alarm system has been in place since July. Still, residents would have just minutes to evacuate their homes.
Reducing the Pressure
Nicolas Karr from France's National Forests Office told the BBC it would be a tricky operation. "We are about at 3,200 meters high, there's no road, only helicopter access, and it's also an area prone to avalanches," he said in an interview Wednesday. "We don't have much time to operate because after mid-October, we don't know if the weather will be OK to go on with our work."
The lake is believed to be the product of melted surface snow which became trapped under the glacier after natural drainage routes froze up.
dgs -- with wire reports
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