Bhutan continues to face the risk of glacial lake flooding
18 Sep 2014 by Yusuke Taishi, Regional Technical Specialist
In Bhutan, about 5,000 meters above sea level, meltwater trickles down from glaciers to form some of the greatest rivers in the world and provide freshwater and energy to nearly 1.3 billion people throughout the Himalayas.
But with the effect of climate change, glaciers are melting too fast, jeopardizing an economy mostly based on hydropower production, but also endangering lives. Water can accumulate in unstable lakes on the glaciers, and when these lakes become too heavy, their natural barriers burst , setting loose a massive volume of water, boulders and mud, causing significant damages in the valleys below.
Between 2008 and 2013, the Government – with our support and financial assistance from the Least Developed Countries Fund, the Government of Austria and the World Wildlife Fund – successfully lowered the water level of Lake Thorthormi, a glacial lake that ranked as one of the most dangerous in the country.
Bhutanese men and women trekked to an altitude of 4,500 meters above sea level to excavate moraine and rocks in near-freezing water against the strikingly cruel contrast of beautiful ice-capped Himalayan Mountains. It is an image that vividly depicts the unfairness associated with climate change and the fact that these communities who have little or nothing to do with global warming bear the brunt of its impact.
After more than 5 years of hard work, involving a total excavation of 21,000 cubic meters of soil and rock, water levels were reduced by 5 meters in the lake, avoiding major human and economic losses for the communities downstream. Early warning systems were installed to warn inhabitants at the first sign of dam collapses, and now cover 90 percent of households in 21 of the most vulnerable communities in the country.
The peace of mind that the project brought to the people living in the valleys below the glacier is immeasurable, but for how much longer? There are more than 20 glacial lakes in Bhutan alone that are considered at risk of outburst, and many more in other nations of the Himalayas.
The experience we gathered from the project is now being shared with Nepal and Pakistan where we support similar initiatives. But most importantly, this unprecedented effort by the Bhutanese people is a great example of a country taking charge and tackling climate change head-on.