Nepal faces fresh flood risk as new barrier lake forms near Bhote Koshi
A fresh flood risk persists in downstream areas of the Bhote Koshi River in Nepal's Rasuwa district after a new barrier lake formed near the river's source, with Chinese authorities warning that the lake could breach, officials said on Thursday.
The Department of Hydrology and Meteorology (DHM) said it had received information from the Chinese side about the formation of a lake at a river blockage site near the Nepal-China border. The information was conveyed to Nepal's Ministry of Foreign Affairs by the Chinese government, according to the department.
Chinese authorities have estimated that around 2 million cubic metres of water had accumulated in the lake by Thursday morning, while another 3 million cubic metres could enter it over the next three days, raising concerns about a possible breach. The lake has formed near the confluence of the Chhochen Khola and Purepu Tsangpo rivers in Nepal, which originate in Tibet and flow into Nepal as part of the Bhote Koshi river system.
The development comes a day after a devastating flash flood swept through central Nepal, killing hundreds. The DHM's Flood Forecasting Division has warned that the risk of another flood remains in the Bhote Koshi and Trishuli river areas, and urged people to stay away from the rivers and remain in safe places until further notice.
The department has also asked people living in downstream areas of the Bhote Koshi River to take precautionary measures and stay away from river banks. Travellers, security personnel and those involved in search and rescue operations have also been advised to remain alert in view of the potential danger.
Chinese authorities are monitoring the lake and conducting flood simulations and risk assessments to determine the possible consequences of a breach and prepare for emergency response.
Meanwhile, during an all-party meeting called by Rabi Lamichhane, president of Nepal's ruling Rastriya Swatantra Party, on Thursday, political leaders cutting across party lines called for diplomatic consultations with China to tackle cross-border glacier risks and recommended establishing a robust disaster management system.
The situation highlights the growing threat of glacial lake outburst floods in the Himalayan region, where rising temperatures are causing glaciers to melt rapidly. Such floods can release large volumes of water and debris suddenly, posing significant risks to downstream communities. The Bhote Koshi river is known for its steep gradient and fast flow, which can amplify the impact of any sudden water release.
Nepal and China have a history of cooperation on transboundary river management, but the current incident underscores the need for more effective early warning systems and coordinated disaster response mechanisms. Local authorities in Rasuwa district have been placed on high alert, and community volunteers are assisting in spreading awareness among residents in vulnerable areas.
Experts say that while the immediate risk depends on the stability of the natural dam, continuous monitoring and timely evacuation are crucial to minimising casualties. The formation of such lakes after earthquakes or landslides is not uncommon in the region, but the speed at which water accumulates can make them particularly dangerous.
The DHM has advised people not to panic but to remain vigilant and follow official instructions. It has also urged local administrations to keep relief materials and rescue teams ready in case the situation worsens. As the world watches, the coming days will be critical for the safety of thousands living along the Bhote Koshi and Trishuli river corridors.
