Bhutan GLOF Disaster: Gasa Hot Spring Complex Washed Away, Highway Severed
A glacial lake outburst flood at Sintaphu Lake in Bhutan has destroyed the Gasa hot spring complex and damaged the Punakha-Gasa highway.
A devastating glacial lake outburst flood (GLOF) at Sintaphu Lake has struck the Gasa district of Bhutan, leaving a trail of destruction in its wake. The sudden surge of water has completely washed away the renowned Gasa Tshachu hot spring complex and caused significant damage to critical infrastructure, including the Punakha-Gasa highway.
The Moment of Impact
The reported outburst occurred on the evening of Thursday, October 29, at Sintaphu Lake, located near Wakila Mountain in Lungo, Laya Gewog. By approximately 8:15 pm, the floodwaters had reached Taktsemakhang, where they tore through a section of the road connecting the remote highland community of Laya, forcing an immediate closure of the route.
Laya, known as one of the most isolated highland settlements in Bhutan, faced an immediate threat. In response, authorities activated warning sirens and carried out precautionary evacuations in areas deemed high-risk. Fortunately, as of the morning of October 30, no deaths or injuries have been reported.
Infrastructure and Tourism Hit
The impact on the region's landmarks and connectivity has been severe:
- Gasa Tshachu Hot Spring: The popular complex, situated beside the Mo Chhu River, was swept away by the torrents.
- Punakha-Gasa Highway: A section of this Secondary National Highway, specifically near the 31.85-kilometre mark, has been entirely washed away.
Due to the collapse of the highway, authorities have closed the road to all traffic until further notice. Travelers are being urged to postpone any non-essential trips or seek alternative routes.
Understanding the Danger: What is a GLOF?
A Glacial Lake Outburst Flood occurs when the natural barriers—known as moraines—that hold back water in a glacial lake breach or weaken. This leads to a sudden, violent release of water that rushes through mountain valleys, carrying a lethal mix of mud, boulders, and debris, which can obliterate everything in its path.
Sintaphu Lake is a high-altitude body of water at the headwaters of the Mo Chhu. It is officially listed as one of Bhutan's 17 potentially dangerous glacial lakes. While this classification indicates a need for constant monitoring rather than a certainty of failure, the risks are real. Between May and June 2023, specialists studied the lake's terrain, the feeding glacier, and the moraine barriers, installing monitoring equipment to mitigate such risks.
Cross-Border Alerts: India on High Alert
The disaster has sent ripples of concern across the border into India. The waters from Sintaphu Lake feed into the Mo Chhu, which eventually joins the Pho Chhu to form the Punatsangchhu. This river later enters India as the Sankosh River.
Following the outburst, precautionary warnings were issued for North Bengal, with communities along the Sankosh River and its tributaries advised to move to safer ground. The Central Water Commission (CWC) issued a special flood advisory for the states of Assam and West Bengal, specifically warning of a sudden rise in water levels in the Dhubri and Alipurduar districts.
As authorities in Bhutan continue to assess the volume of water released and the full extent of the downstream impacts, both Bhutanese and Indian officials remain on high alert to prevent further loss of life or property.