The water rationing in Bangalore, Mysore and other places appears to be imminent in a week or 10 days as the level  in the Krishnaraja Sagar reservoir dropped to 73 ft as on Tuesday against the maximum level of 124.80 ft. Officials say water could  last only for one month and Mysore and Bangalore may have to depend on borewells till the monsoon arrives.

The KRS level is dropping drastically with the inflow down to 352 cusecs and an outflow of 706 cusecs. “Last  March, the level in the dam was 100.69 ft with an inflow of 346 cusecs and outflow of 4,944 cusecs. This time, the outflow has been  reduced as there is no water in the dam. With the reduction in level, water will have to be released from dead storage. Only 15 tmc ft  of water is now usable,” sources said.

Authorities will then have no other option but to supply water on alternate days. 

Cauvery Niravari Nigam Ltd chief engineer Vijay Kumar said the amount of water supplied from KRS has not dropped and it continues to supply 600 cusecs to Bangalore, Mysore and other places. However, he did not reply when asked how long this supply will continue.

However, according to sources, the supply will come down by 25-30 per cent till the water level reaches the first level of dead storage (between 70 and 60 feet marks). Water in this level is expected to last from 45 days to two months, sources said.  Once it goes below 60 feet, pumping will come down by 50 per cent.

However, authorities are  expecting rains by then and hope things will improve before the water from second level dead storage is used.

Meanwhile, in Mysore, the Vani Vilas Water Works is ready with the emergency jackwell pump at the Hongalli pumping station.

Though the drop in level in KRS has slightly affected pumping, authorities say it will not affect distribution. “Due to fluctuation in water level, pumping is stopped for 2-3 hours a day. However, we are getting about 85 per cent normal supply  which may continue for another 15-20 days till the water level reaches 70 ft following which the jackwell has to be made operational,”  sources said.

From KRS, Mysore gets 200 MLD water from its pumping stations in Hongalli, Belagola and Melapura. Hongalli alone pumps 90 MLD of water. But the jackwell at Hongalli will be able to pump only 50 to 60 MLD.

In Belagola and Melapura pumping stations, once the water level goes down, sand bags will be used to raise the surface level of water for pumping.

However, District Minister S A Ramdas told reporters on Tuesday that emergency pumping started from Monday and water is being  pumped from three 250 HP pumps. Stating that only 50 MLD water is being pumped from Hongalli in place of 90 MLD, he asked  people to co-operate.