India’s Reservoir Storage At 70%: At 10-Year Low 

Syllabus: GS3/Agriculture; Water Resources

Context

• As southwest monsoon withdraws recently, India’s reservoir storage remains below the decadal average, raising concerns over irrigation, drinking water and hydropower.

Key Highlights

• According to the Central Water Commission (CWC) live reservoir storage report dated September 24, 2026, water stored in 178 major reservoirs stands at about 70% of total capacity.
• It is below the 10-year average of 76.62% and the 79% storage recorded during the same period in 2025.
• India’s cumulative rainfall was 12% below normal.
• The monsoon accounts for more than 70% of India’s annual rainfall, making it crucial for replenishing reservoirs, groundwater and surface-water systems.
• The situation coincides with drought declarations in parts of Maharashtra and Karnataka.

Regional Reservoir Status

• South India (Most Concerning): The southern region comprising Andhra Pradesh, Telangana, Karnataka, Kerala and Tamil Nadu has recorded the lowest reservoir storage.
  • Current storage: 27.926 BCM (50% of capacity)
  • Previous year: 87.25%
  • Rainfall: 23% below normal as of September 28
  • The sharp decline has implications for irrigation, drinking-water availability and hydropower generation.
• East and Northeast India: Across 31 reservoirs in Assam, Bihar, Jharkhand, Meghalaya, Mizoram, Nagaland, Odisha, Tripura and West Bengal:
  • Storage: 16.157 BCM (73% of capacity)
  • Seasonal rainfall deficit: around 25% in much of the region, except Odisha and some parts of West Bengal.
• Northern India: The 11 reservoirs in Himachal Pradesh, Punjab and Rajasthan show a substantial decline:
  • 2026: 62% (12.431 BCM)
  • 2025: 92.3%
• Western and Central India:
  • Gujarat, Maharashtra and Goa: 32.664 BCM or 84.61%, compared with 95.79% in 2025.
  • Chhattisgarh, Madhya Pradesh, Uttar Pradesh and Uttarakhand: 41.568 BCM or 85.55%, against 91.89% in 2025.

Monsoon Deficit and El Niño

• The southwest monsoon contributes over 70% of India’s annual rainfall and replenishes reservoirs, groundwater and other surface-water bodies.
• However, cumulative rainfall was 12% below normal.
  • June recorded a deficit of 35.4%, August 16.3%, while July was around 1% above normal and September 1–28 recorded a 5% deficit.
• The strengthening El Niño, a periodic warming of the central and eastern tropical Pacific Ocean, has been associated with increased rainfall variability and prolonged dry spells.
• However, ENSO is not the sole determinant of Indian monsoon performance; regional atmospheric and oceanic factors also influence rainfall.

Implications for India

• Agriculture: Reduced irrigation availability and greater dependence on groundwater.
• Drinking water: Stress on urban and rural water supplies during the dry season.
• Hydropower: Lower reservoir levels can constrain electricity generation.
• Food security: Water shortages may affect crop yields and agricultural incomes.
• Inter-state water relations: Scarcity can intensify disputes over shared river waters.
• Drought vulnerability: Poor monsoon performance can translate into hydrological and agricultural drought even when annual rainfall deficits appear moderate.

Way Forward

• India needs to move from rainfall-dependent crisis management to integrated water-resource management. Priorities should include:
  • Basin-level water budgeting and reservoir coordination.
  • Expansion of rainwater harvesting and aquifer recharge.
  • Micro-irrigation and water-efficient cropping patterns.
  • Greater use of real-time reservoir and groundwater data.
  • Drought-resilient agriculture and climate-informed crop planning.
  • Rejuvenation of traditional water bodies and wetlands.
  • Strengthening early-warning and anticipatory drought-management systems.

Source: IE