Nepal Plans Major Glacial Lake Drainage Project to Prevent Floods

Nepal will start a project this fiscal year to drain four high-altitude glacial lakes to reduce flood risks following a recent disaster that killed more than 1,400 people. Rescuers are still searching for more than 5,000 missing people in the border region after an August glacier collapse caused landslides and flash floods.

Project Details

Design work and detailed studies for the central and eastern lakes of Thulagi, Lower Barun, Lumding Tsho and Hongu II will begin in the fiscal year running until mid-July 2027. These lakes sit at heights from 4,050 metres to 5,483 metres and were flagged in a 2020 report by the United Nations Development Programme and ICIMOD. Workers will build gated structures to drain water into nearby rivers in a regulated way, though they face health risks from high-altitude work and sudden floods. The fifty-million-dollar project is funded by the Green Climate Fund, the UNDP, and the government, and could take up to six years to finish according to Sanjeeb Baral, executive director of Nepal's Centre for Hydrology and Water Resources Research.

Wider Impact

The project will also include installing sensors, setting up a flood forecasting and warning system, and building downstream resilience. Nepal has faced about 26 Glacial Lake Outburst Flood events over the past four decades, losing over 300 lives and property worth millions of dollars each year. Prime Minister Balendra Shah recently told the United Nations that climate change is driving these disasters despite the country having very low emissions, adding that cash-strapped Nepal needs nearly $5 billion for early recovery.

Context

Glacial lakes form when melting glaciers leave behind large bodies of water trapped by loose rock and ice dams that can easily break under pressure. Lowering water levels through engineered canals helps prevent sudden outbursts that threaten millions of people living in mountain valleys below.