How will the melting of Himalayan glaciers have a far-reaching impact on the water resources of India?

Himalayan glaciers — the 'Third Pole' — feed the Indus, Ganga and Brahmaputra systems on which nearly half of India's population depends. ICIMOD's Hindu Kush Himalaya assessments warn that glaciers could lose a third of their ice by 2100 even at 1.5°C warming, and far more under high emissions.

Far-reaching impacts on water resources

• Deceptive plenty first: accelerated melt initially raises river flows, swells glacial lakes and triggers outburst floods — Kedarnath (2013), Chamoli (2021) and the South Lhonak–Teesta disaster (2023).
• Scarcity later: after 'peak water', dry-season discharge declines; the Indus, most dependent on meltwater, faces the sharpest stress, threatening Punjab's irrigation economy.
• Agriculture: shrinking lean-season flows hit rabi irrigation across the Indo-Gangetic plain and deepen dependence on already-stressed groundwater.
• Hydropower and dams: erratic discharge and heavy sediment-debris loads endanger projects — Tapovan-Vishnugad was wrecked in 2021 and Teesta-III washed away in 2023.
• Drinking water: Himalayan towns face shortages (Shimla, 2018), and NITI Aayog notes nearly half of Himalayan springs are drying.
• Deltas: altered freshwater-sediment flux worsens salinity intrusion in the Sundarbans.

India needs sustained cryosphere monitoring, GLOF early-warning systems, climate-proofed hydropower siting, basin-level cooperation with neighbours and demand-side water efficiency under the National Mission for Sustaining the Himalayan Ecosystem.