KATHMANDU, March 6: A new study has revealed that three glacial lakes in Tibet are in very critical condition, posing serious threats to people living downstream on the banks of the Bhotekoshi River.
The study, jointly carried out by the Central Department of Geography at the Tribhuvan University (TU) and the Asian International River Center at the Yunnan University of China, has concluded that You-Mo-Jian-Co, Qui-Ze-La-Co and Jia-Long-Co glacial lakes, which are located within the watershed area of the Bhotekoshi River, are highly vulnerable.
"If these lakes burst out, severe impacts could be felt along the Bhotekoshi River, particularly between Tatopani and Dolalghat areas on the Araniko highway," said Narendra Raj Khanal, a professor at the TU´s Central Department of Geography. According to Khanal, who was the team leader for the one-year-long study, there are several other potentially dangerous glacial lakes in the Bhotekoshi River´s watershed area but three could possibly burst out in future.
"These three glacial lakes in the Tibetan region require constant monitoring and immediate mitigation," said Khanal. "Our government should also be constantly monitoring these lakes, considering the threats that the Nepali people face." Khanal also stressed the need for setting up of effective early warning systems to protect human lives in events of Glacial Lake Outburst Flood (GLOF) in Tibet.
The finding of this new study, the final report of which is yet to be published, implies that the risk of GLOF in Nepal is higher than what is generally assumed. In Nepal, understanding of GLOF has been largely shaped by scientific studies carried out by the International Center for Integrated Mountain Development (ICIMOD). A 2011 report by the ICIMOD states that Nepal has 21 potentially dangerous lakes - six of which need immediate mitigation measures.
"In our new study, we have tried to see the risk of GLOF in Nepal beyond the northern border," said Khanal, who was also a member of the team that prepared the ICIMOD´s report on Nepal´s glacial lakes. "We cannot ignore possibilities of GLOF in the Tibetan region."
Experts also stress the need for mitigating the risk of GLOF in four glacial lakes of Nepal, which the ICIMOD report says are as critical as Tsho Rolpa and Imja. Currently, mitigation measures, like lowering water level of glacial lakes, have been taken only in Tsho Rolpa and Imja. Such measures have not been initiated as yet in other equally vulnerable lakes like Lower Barun, Lumding, West Chamjang and Thulagi.
"These four glacial lakes also need immediate mitigation measures," said Pradeep Mool, Coordinator of Cryosphere Initiative at the ICIMOD. "But, mitigation measures are very costly. Millions of dollars are required just for transporting equipment to glacial lake areas. So, cost-benefit analysis is done before starting such initiatives. Imja was chosen over other lakes for mitigation measures, considering tourist destinations downstream."