• Reservoirs and dams are critical for irrigation, drinking water supply, hydropower, flood control, and industrial use.
• Over the years, sedimentation (accumulation of soil, silt, and debris in reservoirs) has reduced their storage capacity significantly.
• According to a recent IISER Bhopal study, India’s major dams have already lost about 50% of their designed storage capacity.

Key Findings of the IISER Study

1. Sedimentation Impact:
   • Sediment inflow from rivers and catchment areas is filling reservoirs faster than earlier estimates.
   • This reduces the “live storage” capacity (usable water volume).
2. Regional Variation:
   • Dams in Himalayan and central Indian regions are more vulnerable due to higher soil erosion and deforestation.
   • Reservoirs in peninsular India also face challenges due to unplanned urbanization and agriculture.
3. Future Projections:
   • If current trends continue, many large reservoirs may become ineffective within 30–40 years.
   • This poses a direct risk to food security, water supply, and hydropower generation.

Implications for India

1. Water Resources
   • Decline in water storage reduces availability for drinking water, irrigation, and industries.
   • May intensify water disputes between states.
2. Agriculture
   • Irrigation systems dependent on reservoirs will suffer.
   • Farmers may face increased vulnerability to droughts.
3. Energy Security
   • Hydroelectric power generation capacity will reduce.
   • Increased dependence on fossil fuels may hurt climate goals.
4. Disaster Management
   • Reduced flood storage capacity increases the risk of floods and flash floods.
   • Sudden release of water during heavy rainfall may cause downstream destruction.
5. Economic and Social Costs
   • Higher costs of water supply and irrigation.
   • Migration and rural distress may rise in water-scarce regions.

 Government Initiatives & Solutions

1. National Water Policy (2012)
   • Emphasizes efficient water use, recycling, and conservation.
2. Dam Rehabilitation and Improvement Project (DRIP)
   • Focus on repairing, maintaining, and modernizing ageing dams.
3. Catchment Area Treatment Programs
   • Afforestation, soil conservation, and land management to reduce siltation.
4. Use of Technology
   • Satellite-based monitoring of sedimentation and reservoir capacity.
   • Adoption of dredging and desilting technologies.
5. Alternative Measures
   • Promotion of rainwater harvesting, groundwater recharge, micro-irrigation (drip/sprinkler).
   • Focus on small check dams and decentralized water storage systems.

UPSC Relevance

• GS Paper 1 (Geography): Water resources, sedimentation, landforms.
• GS Paper 2 (Polity & Governance): Water disputes, inter-state coordination.
• GS Paper 3 (Economy, Environment, Disaster Management): Agriculture, irrigation, climate change, hydropower, environmental conservation.
• Essay / Ethics: Sustainable water use, balancing development and environment.

Value Addition (For Mains/Essay)

• Quote: “Water is the elixir of life, but sediment is its silent enemy.”
• Example: Bhakra Nangal Dam (Punjab–HP) has lost around 30% storage capacity since its construction.
• International Comparison: The USA and China also face sedimentation issues but invest heavily in sediment flushing and river training works.

Conclusion:
The sedimentation crisis in Indian reservoirs is a silent but serious threat to water security, agriculture, and energy sustainability. Immediate steps like catchment management, desilting, technological interventions, and policy reforms are needed to secure India’s water future.