Guwahati: A continued decline in winter snow across the Brahmaputra basin is raising fresh concerns over water availability, agriculture, and hydropower in Northeast India, according to the latest HKH Snow Update 2026 released by the International Centre for Integrated Mountain Development (ICIMOD).
The report finds that snow persistence in the Brahmaputra basin dropped 6.1% below normal during the November 2025–March 2026 winter season, marking the second consecutive year of below-normal levels.
Snow persistence, or how long snow remains on the ground after snowfall, plays a critical role in sustaining river flows during the pre-monsoon months. Any decline directly impacts early summer water availability downstream.
A worrying regional pattern
The findings are part of a broader trend across the Hindu Kush Himalaya (HKH), often called the “Third Pole”, which supports water needs of nearly two billion people.
According to ICIMOD scientist Sher Muhammad, who authored the report, the region is seeing a sustained drop in snow reserves.
“Between 2003 and 2026, the HKH region experienced 14 winters with below-normal snow persistence. This year marks the fourth consecutive deficit, with snow levels falling to 27.8% below average, lower than last year’s record,” the report notes.
On average, snowmelt contributes about 23% of total river runoff in the HKH region, making these changes particularly significant.
What it means for the Brahmaputra
While the decline in the Brahmaputra basin is less severe compared to western river systems, the implications remain serious.
The report notes that snow levels in the basin have fluctuated sharply in recent years, from 27.7% above normal in 2019 to 27.9% below normal in 2025, before settling at a 6.1% deficit this year.
This continued negative trend could affect early summer river flows, hydropower generation, and agricultural water supply, especially in downstream regions such as Assam.
Growing water stress risks
Across the HKH region, 10 of 12 major river basins recorded below-normal snow persistence this year, signalling a widespread decline. Only the Ganges and Irrawaddy basins saw above-normal snow levels.
Experts warn that reduced snow reserves, combined with erratic rainfall, could lead to heightened water stress in the coming months.
The report calls for early warning systems for water shortages, better water allocation planning, stronger drought preparedness, and greater regional cooperation.
As climate variability intensifies, ICIMOD stresses the need for adaptive, science-driven water management strategies to safeguard river systems like the Brahmaputra.