Kathmandu, October 2

The government has drained the water level of Imja, one of the fastest growing glacial lakes in the Himalayas, in Solukhumbu by more than two metres.

Nepal had begun draining water from the glacial lake from September 24 to save over 12 villages from glacial lake outburst floods.

A team from the Department of Hydrology and Meteorology released water through the lake’s main gate. Department of Hydrology and Meteorology informed the water level has come down by over two metres and 3.5 metres more water will be drained.

“We have mitigated the risk of glacial lake outburst floods by lowering the water level to below ‘risk level’ and for that we are thankful to all our supporters” Rishi Ram Sharma, director general at the department told The Himalayan Times.

Before starting the draining process, the department had alerted residents of villages downstream about the dangers of rising water level in Imja Lake and the Dudhkoshi River.

Sharma said the technical team is releasing water at the rate of three cubic metres per second, and the team plans to drain a total of 4 million cubic metres.

The project was initiated by the Department of Hydrology and Meteorology under the $ 7.2 million Community Based Flood and Glacial Lake Outburst Risk Reduction Project.

The project aims to reduce possible loss of human lives and infrastructure from GLOFs in Solukhumbu and downstream areas of Mahottari, Siraha, Saptari, and Udaypur.

The Nepali Army constructed the outlet gate to release water accumulated since June 1 this year to drain water by 3.5 metres — the level at which the lake becomes GLOF risk-free. NA personnel constructed a three-metre wide and 1.5-metre deep outlet channel to drain the water. As many as 40 personnel and 62 civilians were involved in the task.

Nepali Army Spokesperson Tara Bahadur Karki said it was the NA’s first experience in a disaster risk mitigation programme. “Although we have been involved in various rescue operations, working in disaster risk mitigation at a height of 5,010 metres was the army’s first such task,” he said.

After draining more than two metres deep the glacial lake is now 180 metres deep, two kilometres long, 650 metres wide, and is spread over 130 hectare. The surface area of the lake is said to have expanded from 0.4 to 1.01 square kilometres between 1984 and 2009 due to rapid snow-melt.

An estimated 96,562 people are living in vulnerable areas downstream of Imja Lake. The programme to drain the lake water was funded by United Nations Development Programme and the Global Environment Facility.

Nepal is ranked the fourth most vulnerable country in the world in terms of climate change. A total of 3,808 glaciers and 1,466 glacial lakes have been identified in Nepal. These lakes include 21 potentially dangerous lakes, out of which six are at very high risk.

Tso Rolpa and Imja lakes are among them. Around 21 glacial lakes pose high risk of glacial lake outburst floods.