Full Breakdown
Glacial Lake Outburst at Shintaphu Lake Triggers Flood Alerts in West Bengal and Assam
By Drooid · · How we work
In this breakdown
01
Background & Context
Shintaphu Lake lies in Bhutan’s Gasa district, below Wakila Mountain in the Layo Gewog’s Lungo area. It is one of 17 glacial lakes in Bhutan identified as potentially dangerous and drains into the Punatsangchhu river basin, which becomes the Sankosh River after crossing the India-Bhutan border. Seasonal glacier melt and rising temperatures in the Eastern Himalayas have increased the risk of sudden lake breaches, prompting Bhutanese and Indian authorities to monitor the basin closely.
02
Core Event
On October 29, residents of Bhutan reported a sudden surge of water from Shintaphu Lake. The outburst sent a rapid flow downstream through the Mo Chhu tributary into the Sankosh system. Sirens were sounded in Bhutan, and communities along the riverbanks were moved to safer ground. Indian officials issued a special flood advisory for vulnerable districts in West Bengal and Assam, warning that water levels could rise sharply along the Sankosh River.
03
Data & Statistics
- The outburst released approximately 7.4 million m³ of water, according to NDTV Profit.
- No casualties have been reported.
- Two Bailey bridges in Bhutan were reported collapsed.
- Floodwaters reached the PHPA-II dam, which was emptied by opening all sluice gates.
- A water-level monitoring station at Taktsimakhang did not trigger an alert at the time of the surge, per Bhutan’s National Centre for Hydrology and Meteorology (NCHM).
- The Indian advisory estimated that floodwater could reach the India-Bhutan border within six to eight hours.
- West Bengal Forest Minister Manoj Kumar Oraon warned that the surge could reach the Kumargram stretch of the Sankosh within one to one-and-a-half hours.
04
Official Statements & Responses
- The Government of India issued a flood advisory for Alipurduar (West Bengal) and Dhubri (Assam), directing authorities to monitor river conditions and take precautionary measures.
- NDRF and State Disaster Response Force teams were deployed to Tufanganj and Boxirhat in Cooch Behar district, positioned along the Sankosh near the Assam border.
- West Bengal Forest Minister Manoj Kumar Oraon delivered a video message urging residents of Alipurduar, Kumargram, Pakriguri, Bholka and nearby tea estates to evacuate to higher ground.
- BJP MP Raju Bista (Darjeeling) posted a safety alert on X, urging all residents in the Sankosh catchment to move to a safe distance.
- The Central Water Commission instructed monitoring sites at Barobisha, Sankosh LRP, Golakganj and Baladoba to track river conditions, report significant changes, and take immediate precautions.
05
On-the-Ground Reports
Local authorities sounded sirens along the Mochu River and downstream of Punatsangchhu. Residents in Alipurduar district and Dhubri district were advised to move to safer locations without waiting for rising water. In Bhutan, people near the lake were evacuated after the breach, and the affected bridges were inspected.
06
Conflicting Reports & Gaps
While NDTV Profit quantified the released water at roughly 7.4 million m³, other outlets described the volume as “unclear.” The NCHM official noted that the Taktsimakhang station had not issued an alert, leaving the precise timing and magnitude of the breach uncertain. Updated river-level readings from downstream Indian stations have not yet been released, and official confirmation of any flood impact in West Bengal or Assam remains pending.