Karnataka: reservoirs and the south interior outlook

Karnataka's reservoirs supply drinking water to Bengaluru and other cities, power, and irrigation. After a weak monsoon, they enter the dry months well below last year.

Total storage (fact). The state's KWRIS dashboard, run by ACIWRM for the Water Resources Department, shows usable (live) storage in 23 major reservoirs at 291.2 TMC on 17 October 2026, against 424.3 TMC on the same day in 2025. By our calculation that is about 31% less. Krishna basin reservoirs held 252.8 TMC and the four Cauvery basin reservoirs 38.3 TMC.

Cauvery basin dams. Tamil Nadu Agriculture Department data for 17 October show Krishna Raja Sagar at 47% of capacity (100% a year ago), Kabini 54% (98%), Harangi 57% (95%) and Hemavathy 42% (88%). These percentages are calculated from the published storage and capacity.

Rain so far in October. IMD's figures for 1–17 October show South Interior Karnataka 44% short, North Interior Karnataka 89% short and Coastal Karnataka 36% short.

The outlook (forecast). IMD's Northeast Monsoon Outlook expects normal to above-normal rain only in southern Tamil Nadu and southern Kerala. Most other areas, including South Interior Karnataka, lean below normal.

Rain this week. IMD's Karnataka agromet bulletin of 16 October forecast heavy rain at one or two places over coastal and south interior Karnataka over the following days, which may help some catchments.

What you can do. At home, fix leaks, reuse water where safe and follow advisories from BWSSB or your local body.

TMC means thousand million cubic feet. One TMC is about 28.3 billion litres.

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