Kathmandu, August 27: According to scientific assessments by the International Centre for Integrated Mountain Development (ICIMOD) and the Nepalese government, 47 glacial lakes have been identified as “potentially dangerous glacial lakes” (PDGLs). Experts warn that these lakes could trigger glacial lake outburst floods (GLOFs) at any moment, leading to devastating floods in Nepal’s river systems.
Out of these 47 lakes, 21 are located in Nepal, while 25 are situated in Tibet, crossing the border. These lakes are positioned in the upper reaches of rivers that flow southward into Nepal, posing a potential threat to downstream communities and infrastructure.
Disaster management officials and the United Nations Development Programme (UNDP) have specifically highlighted several rapidly expanding moraine-dammed lakes from this list. Immediate action is required to mitigate risks and lower water levels in these lakes.
The most notable lakes include Lower Barun (Talopokhari), Thulagi (Dona), Lumding Tso, Hongu-2/Chamalang South, Tso Rolpa, and Imja Tso.
The threat posed by these high-risk lakes is primarily concentrated in mountainous and hilly districts located along the paths of downstream river valleys. A significant GLOF could severely impact the lives of people and critical infrastructure in these areas.
Eastern and central Nepal, including the Koshi and Bagmati river basins, account for over 85 percent of the total regional risk concentrated in vulnerable areas.
The most at-risk districts include Solukhumbu, which encompasses the Milk Koshi and Imja basins. Sankhuwasabha district lies along the Barun and Arun river valleys. Dolakha district is situated in the Tama Koshi river corridor and may face threats from Tso Rolpa lake. Meanwhile, Sindhupalchowk district is located along the Bhotekoshi and Sun Koshi river valleys, facing potential flood threats from lakes across the Tibetan border.
Additionally, riverside settlements in the districts of Ramechhap, Kavrepalanchok, and Rasuwa are also considered sensitive, particularly in areas surrounding the Trishuli river basin.
In western and far-western Nepal, where the Gandaki and Karnali river basins extend, communities and hydropower projects in several districts are also under direct threat.
These include Manang and Lamjung districts, located in the Marsyangdi river basin below Thulagi lake. Furthermore, Gorkha district in the Budhi Gandaki basin, Mustang and Myagdi districts in the Kali Gandaki basin, and remote areas of Humla, including the Limi valley and Humla Karnali corridor, may also be potentially affected.
Leave a Comment