Water levels in India's main reservoirs in the week to September 11 were at 77 per cent of capacity, down 6 percentage points from a year earlier, government data showed on Friday, reflecting this year's overall weak monsoon rains.

However, a late revival of the rains has propped up the latest level by 6 percentage points from a week earlier and by 5 percentage points from the 10-year average, the data showed.

Weather officials expect the monsoon rains to remain active in the western region next week.

Water level in reservoirs is vital for hydropower generation and irrigation. Reservoirs also provide water later in the year to irrigate winter crops such as wheat and rapeseed.

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