Glacial lakes expand, there is a danger of them bursting due to water pressure, or because of earthquakes and avalanches falling into them. As the average temperature in the mountains rises by 0.056 Celsius every year, the threat of glacial lake outbursts will only grow.
On top of the perennial risk of earthquakes, new hydropower stations, highways along rivers, bridges and towns will also have to take into account the threat of GLOFs. The flash flood near Nanda Devi in India’s Uttarakhand state in March washed away two hydroelectric plants that were under construction.
There is a warning there for Nepal, which is building cascade projects on the two Bhote Kosi rivers that flow down from China, Tama Kosi, Marsyangdi, and the Arun. In the Gandaki Basin is the particularly dangerous Thulagi glacial lake below Himalchuli, which would directly threaten three major hydroelectric projects along the Marsyangdi River. Scientists monitoring Thulagi have found the glacier has receded by 2km since 1984, the ice replaced by a lake.