Intro (Micro Notes):
• Himalayan glaciers are the source of major perennial rivers – Ganga, Indus, Brahmaputra.
• They store ~12,000 km³ of freshwater, forming the water tower of Asia.
• Climate change has accelerated glacial retreat (e.g., Gangotri receding ~20 m/yr).
Far-Reaching Impact on India’s Water Resources:
1. Altered River Flow Patterns
→ Initial increase in meltwater → floods (short-term)
→ Long-term reduction → drought-like conditions, seasonal river shrinkage
→ Affects rivers like Ganga (supports 40% population), Satluj, Yamuna
2. Agriculture & Irrigation Threats
→ 60% of India’s agriculture is dependent on Himalayan-fed rivers
→ Reduced river flows impact canal systems, cropping cycles, food security
3. Hydropower Generation Disruption
→ Reduced flow affects projects in J&K, Himachal, Uttarakhand (e.g., Tehri Dam)
→ Glacial lake outburst floods (GLOFs) risk damaging infrastructure (e.g., Chamoli disaster 2021)
4. Drinking Water Scarcity
→ Glacial meltwater is vital for northern states: Punjab, Haryana, UP
→ Drying up of tributaries → stress on groundwater
5. Wetland & Groundwater Recharge Impact
→ Decreased surface water → less infiltration → groundwater depletion
→ Affects floodplains like Indo-Gangetic Plain
6. Ecosystem & Biodiversity Disruption
→ Changing flow affects aquatic biodiversity & riparian habitats
7. Socio-political Stress
→ Water-sharing tensions may rise among Indian states & with neighboring countries (e.g., Indus basin, Brahmaputra basin)
Conclusion (Micro Notes):
• Urgent need for glacier monitoring (ISRO-NCPOR data), sustainable water use, interlinking rivers cautiously.
• Promote basin-wide cooperation, afforestation, glacial lake management, and resilient infrastructure.
