Water storage in 178 major reservoirs across India has fallen to 70% of total capacity as the southwest monsoon approaches its end, according to a live storage report compiled by the Central Water Commission (CWC).
The level is below the 10-year average of 76.62% for this period and lower than the 79% recorded during the corresponding period last year.
The CWC report, dated September 24, comes as Maharashtra and Karnataka face drought declarations and several regions report below-normal rainfall.
South India has recorded the most severe decline. The 92 reservoirs monitored across Andhra Pradesh, Telangana, Karnataka, Kerala and Tamil Nadu held 27.926 billion cubic meters, equivalent to 50% of their combined capacity. At the same time last year, storage in the region stood at 87.25%.
The region had received 23% below-normal rainfall as of September 28, according to India Meteorological Department data.
The southwest monsoon normally provides more than 70% of India’s annual rainfall between June and September. It replenishes reservoirs and surface-water bodies used for drinking-water supply, irrigation, hydropower generation and other needs.
Reservoirs in eastern India also show signs of stress. Thirty-one dams across Assam, Bihar, Jharkhand, Meghalaya, Mizoram, Nagaland, Odisha, Tripura and West Bengal held 16.157 billion cubic meters, or 73% of total capacity.
The eastern and northeastern regions recorded a seasonal rainfall deficit of 25%, except for Odisha and some parts of West Bengal.
In northern India, 11 reservoirs across Himachal Pradesh, Punjab and Rajasthan held 12.431 billion cubic meters, or 62% of capacity. Storage in these reservoirs was 92.3% during the same period last year.
The 58 reservoirs monitored across Gujarat, Maharashtra and Goa held 32.664 billion cubic meters, representing 84.61% of capacity. This compared with 95.79% last year.
The 28 reservoirs across Chhattisgarh, Madhya Pradesh, Uttar Pradesh and Uttarakhand held 41.568 billion cubic meters, or 85.55% of capacity. The comparable figure in 2025 was 91.89%.
India’s rainfall was 12% below normal between June 1 and September 28. June recorded a 35.4% deficit, August a 16.3% deficit and September 1–28 a 5% deficit. July rainfall was around 1% above normal.
The weakening reservoir position has been linked to prolonged dry spells and the strengthening El Nino climate pattern. El Nino can influence rainfall and temperatures across regions, but local water conditions also depend on reservoir operations, groundwater recharge, irrigation demand and regional rainfall distribution.
With the monsoon nearing its seasonal end, the scope for a significant improvement in national reservoir storage has narrowed. Low reserves could affect drinking-water planning, irrigation availability, hydropower generation and groundwater stress during the coming dry season.