YK Poudel
As a hotspot for ice loss, Bhutan faces escalating risks from rapidly growing glacial lakes and Glacial Lake Outburst Floods (GLOFs).
The Newcastle University in the UK has partnered with the Druk Holding and Investments (DHI) to study the stability of glacial lakes, assess GLOF risks, and identify necessary adaptation measures.
The collaboration, which began in March 2024 and will run until 2027, will assess the growing threats of GLOFs in the Eastern Himalayas, particularly in Bhutan. The partnership has already invested Nu 19.6 million (USD 19.66 million) in research and monitoring.
The Himalayan region is home to the world’s largest population exposed to GLOFs, with an estimated 1 million people living within 10km of a glacial lake. Bhutan, which is particularly vulnerable, is ranked fourth globally for GLOF risk, with the Punatsangchhu basin identified as one of the most perilous areas.
A recent field visit by the research team to the Thorthomi and Rapstreng Lakes between August and September 2024 confirmed alarming signs of rapid glacier retreat. The glaciers have started melting at an unprecedented rate, with some disappearing altogether.
Professor Rachel Carr, head of physical geography in Newcastle University Newcastle, explained the profound risks GLOFs pose to life, property, and infrastructure, particularly Bhutan’s hydroelectric plants, which are a key contributor to the national GDP.
“Bhutan is the most vulnerable country globally to GLOFs because its population, infrastructure, natural heritage and hydro-power generation capacity lie downstream of glacial lakes,” she said. “The primary employment sector and subsistence farming is vulnerable to GLOF as well as rising transboundary hazards.”
The project aims to establish a long-term international collaboration focused on GLOFs and water and energy resources in Bhutan. A key component of the study will involve the Punatsangchhu catchment, identified as one of the highest-risk areas globally for GLOFs.
Through this partnership, the team plans to deploy a network of low-cost sensors to monitor glacial lake dynamics, assess potential GLOF triggers, and integrate data with existing early warning systems (EWS). This will involve monitoring key factors such as lake levels, temperature changes, moraine stability, and other critical parameters to forecast GLOF events and improve disaster preparedness.
The research also focuses on the stability of the moraine dam at Thorthomi Lake, one of the most critical sites for GLOF risks in the country.
In collaboration with the local Lunana community, the team is gathering traditional knowledge and community insights to guide adaptation measures. This includes documenting the impact of recent GLOF events, such as the formation of a beach around Thorthomi Lake due to flooding.
The challenges of monitoring and managing GLOF risks in the country are compounded by the country’s remote terrain and limited infrastructure. Bhutan has over 2,500 glacial lakes, with 65 classified as high-risk for GLOFs.
According to Bhutan Glacial Lake Inventory 2021, Bhutan has 567 glaciers covering 55.04km square.
The National Centre for Hydrology and Meteorology (NCHM) reports that extreme weather events, including flash floods, landslides, and other climate-related disasters, have increased significantly in recent years. Between 2016 and July 2022, Bhutan experienced over 32 extreme weather events, causing widespread damage to infrastructure, crops, and livelihoods.
A study by the National Centre for Hydrology and Meteorology (NCHM) reveals that Bhutan’s glaciers are particularly sensitive to climate change, with warming in the Hindu Kush Himalayas expected to exceed 1.5°C by 0.3°C.
An ICIMOD study also warns that global warming of 2°C will cause irreversible damage to Earth’s frozen regions, impacting millions.
To address climate risks, Bhutan is implementing the “Supporting Climate Resilience and Transformational Change in the Agriculture Sector” project (2020-2025). As part of this, NCHM has developed tailored climate products for agriculture, benefiting over 1,000 farmers and extension officers.
In addition, NCHM is involved in the World Bank-funded Multi-Hazard Risk Assessment Project (2021-2025), with USD 0.6 million in funding.
Supported by UNDP, the Flood Decision Support System for the Amochu Basin has been completed. This is a part of the Nu 28 million work on establishment of Comprehensive Flood Forecasting and Early Warning System for Amochhu Basin under Phuentsholing Township Development Project, under the CDCL and DHI funding.
This system will provide forecast-based flood warnings up to 72 hours in advance, helping to reduce flood-related losses through early alerts and improved monitoring.
