The Bhutanese Leading the way.
The National Center for Hydrology and Meteorology (NCHM) is set to begin a pilot project to lower water levels at Thorthormi Lake, the country’s most dangerous glacial lake, using a siphon method. The decision to test this approach was made due to its simplicity and cost-effectiveness.
The siphon method is simply inserting a pipe in a higher body of water without any digging and using natural suction and gravity to get the water out.
Sonam Lhamo, Principal Hydromet Officer at the NCHM, said, “The only measure we have planned for now is the use of the siphon method at Thorthormi Lake, and we will soon be implementing this there, after studying the feasibility.”
She added, “We are still in the planning stage. This is not a full-scale operation; it is simply a pilot to assess whether the method will work.” A team of experts has been deployed to the Lunana to test the feasibility of this method.
The method will be tested on an existing channel at Thorthormi Lake. Sonam Lhamo said, “We chose Thorthormi because numerous studies have identified it as one of the most critically dangerous lake in Bhutan.”
The siphon method, based on hydraulic principles, has been applied successfully in other countries. “Only after this pilot project can we determine its feasibility and as part of Bhutan’s 13th Five-Year-Plan, NCHM is also working to enhance early warning systems by integrating them into a unified framework,” Sonam Lhamo said.
“There is an ongoing project with the World Bank, and we aim to develop updated risk vulnerability maps by the end of next year,” Sonam Lhamo added, noting that surveys are currently underway.
If successful, the siphon approach could be expanded to other high-risk lakes, offering a significant step toward protecting downstream communities from potential glacial lake outburst floods (GLOFs).
