Bengaluru water supply threatened as key reservoirs drop below half capacity

Water supplies to Bengaluru are facing a severe threat as key reservoirs in Karnataka have recorded critically low storage levels, holding less than half of the water they had at the same time last year. According to data released by the Karnataka State Natural Disaster Monitoring Centre (KSNDMC) on Monday, a 34 per cent rainfall deficit since the onset of the southwest monsoon has left major dams at a fraction of their capacities.

The water scarcity directly impacts Bengaluru and surrounding regions, which rely heavily on the Krishnarajasagar and Kabini dams. The Krishnarajasagar dam, built across the Cauvery river, currently holds just 11.49 TMC of water, representing 23 per cent of its total 49.45 TMC capacity. Similarly, the Kabini dam holds only 6.74 TMC against its full storage level of 19.52 TMC. Both reservoirs were almost completely full during the same period last year.

Data from the KSNDMC revealed that the cumulative water level across Karnataka's 14 major reservoirs stood at 212.9 TMC as of Monday. This is a significant drop from the 595.3 TMC of storage recorded during the same period last year, against a total gross capacity of 895.65 TMC.

The water crisis stems from a poor monsoon season that began on June 1. The state has recorded an overall rainfall of 165 mm, compared to the seasonal average of 249 mm. The Malnad districts, which serve as the primary catchment areas for most rivers originating in Karnataka, received only 263 mm of rain against a normal average of 483 mm.

The situation is also grim in northern Karnataka, where major reservoirs across the Krishna river are experiencing low inflows. The Narayanapura dam recorded zero inflow as of Monday, while the Almatti dam upstream received an inflow of approximately 1,000 cusecs.

In contrast, reservoirs such as Linganamakki and Ghataprabha have experienced increased inflows due to heavy rain in the coastal and Malnad regions. Meteorological forecasts suggest that a good spell of rain is expected across the state before the end of the week, which may help improve reservoir inflows.