Glacier melt and the expansion of glacial lakes are increasing the risk of sudden flood events in Bhutan. The Chamkhar Chhu in Bumthang is among the rivers facing this threat, putting communities along its banks at risk. As climate change accelerates glacier retreat, the need for public awareness and disaster preparedness has become more urgent. To help communities better understand these risks, the National Centre for Hydrology and Meteorology (NCHM) recently conducted a Glacial Lake Outburst Flood, or GLOF, awareness programme in Bumthang.
A recent study on glacial lake hazards and risk in Bhutan identified Bumthang as the country’s second most vulnerable district after Punakha in terms of potential future damage from GLOFs.
The threat comes mainly from the Chamkhar Chhu, which is fed by Chubdha Tsho, Phudung Tsho and another glacial lake. These lakes pose a risk to settlements in the Chamkhar Chhu basin.
According to the study, Chhoekhor Gewog has the highest GLOF risk index in the country. At least 191 buildings in the gewog are exposed to potential floods originating from 14 different glacial lakes. Bumthang town has the highest number of GLOF-exposed buildings in Bhutan, with 283 structures at risk.
NCHM says a GLOF could reach some buildings in Chhoekhor within just 35 minutes.
Meanwhile, the centre reports that river water levels are rising. Studies show that glacier melt and the expansion of glacial lakes are more likely to trigger sudden and potentially destructive flood events than cause a gradual rise in daily river levels.
“To reduce risks to lives and property, we have installed three automatic water-level monitoring stations and five warning sirens along the Chamkhar Chhu. These systems help provide early warnings during flood emergencies,” said Chencho Dema, a hydro-met officer with NCHM.
NCHM conducts similar awareness programmes in high-risk districts, including Punakha, Wangdue Phodrang, Trongsa and Bumthang.
The recent programme in Bumthang brought together sector heads, regional officials, armed forces personnel, De-suups and Red Cross volunteers to strengthen coordination and preparedness in the event of a disaster.
Participants also received briefings on risk reduction measures, emergency communication systems and evacuation procedures. Participants are expected to pass on the information to communities and help raise public awareness.
Chencho Dema said, “Glacial lake outburst floods remain one of the major risks in the area. NCHM has established a GLOF early warning system, and we are here to update stakeholders on the current condition of the lakes and the risks they pose.”
For communities living along rivers such as the Chamkhar Chhu, understanding warning systems, evacuation procedures and flood risks could make the difference between safety and disaster.
Officials say continued awareness programmes and timely information sharing by agencies such as NCHM are critical to ensuring that communities remain prepared, helping to protect lives, livelihoods and property when emergencies occur.
Thinley Dorji, Bumthang
Edited by Sangay Chezom
