Water levels in India's main reservoirs were at 45% of their storage capacity in the week to August 4, down 2% points from a year earlier, government data showed on Thursday.
The latest levels were lower than the last 10 years' average of 47%, but 7% points higher compared with the previous week.
The weather office has retained its forecast for an above-average monsoon this year, boosting hopes of a rise in farm output and income after two years of drought.
Water levels in reservoirs are important primarily for irrigation during the summer and winter months, and for hydropower generation.