Nepal flash floods trigger Gandak alert in Bihar; several districts at risk
The districts facing the most immediate risk in Bihar include West Champaran, East Champaran, Gopalganj and Saran, which are directly or closely connected to the Gandak river system. Authorities have also placed Muzaffarpur and Vaishali under heightened vigilance.
New Delhi: A massive flash flood originating from the Tibet-Nepal border on Wednesday has raised concerns over a possible surge in the Gandak river in Bihar, prompting authorities in the state to step up preparedness in the vulnerable districts.The flash flood struck the Bhote Koshi river in Nepal’s Rasuwa district around 9am and swept away homes, roads, bridges and hydropower infrastructure. The Bhote Koshi and Trishuli rivers, key tributaries of the Narayani-Gandak river system, have witnessed sharp rises in water levels, triggering extensive damage across northern Rasuwa district in Nepal.Media reports suggest close to 100 people have lost their lives in Nepal, with hundreds missing, including 105 Indians.The sudden discharge has prompted high-alert advisories across downstream parts of Nepal, with people living along the Bhote Koshi, Trishuli and Narayani rivers advised to move away from riverbanks and low-lying areas.According to the India Meteorological Department (IMD), the flood wave is moving rapidly downstream, raising concerns over rising water levels along the river system over the next 24 hours and possible impacts on downstream settlements.
The development is significant for Bihar because the Narayani river enters India and becomes the Gandak, one of the major rivers flowing through north Bihar. A sudden increase in discharge in Nepal can therefore translate into a rapid rise in water levels downstream, particularly in areas close to the Gandak and its tributaries.The Bihar government has already put several districts on alert and warned of a possible flood wave of around three metres entering the Gandak river.
Authorities have directed district administrations to monitor river levels, embankments, bridges and low-lying areas and keep evacuation and relief arrangements ready.Districts likely to be impactedThe districts facing the most immediate risk in Bihar include West Champaran, East Champaran, Gopalganj and Saran, which are directly or closely connected to the Gandak river system. Authorities have also placed Muzaffarpur and Vaishali under heightened vigilance because of the potential downstream spread of floodwaters.
Sitamarhi and Sheohar have also been identified as vulnerable districts requiring preparedness, although the actual impact will depend on the volume and timing of water reaching Bihar.West Champaran is likely to be among the first Bihar districts to experience the impact because the Gandak enters the state from Nepal through the Valmikinagar area. From there, the river flows through the northern plains towards Gopalganj, Saran and adjoining districts.
A sharp rise in discharge could put pressure on embankments and low-lying settlements along the river.According to an IMD official, the situation remains fluid because the scale of the flood wave reaching Bihar will depend on how much water is retained or dissipated as it travels through Nepal's mountainous river system. The immediate priority for downstream communities is therefore to follow official advisories, avoid riverbanks and remain prepared for rapid changes in water levels.