Deccan Chronicle        06.01.2011

Is the crisis over? City to swap water with Mandya

Jan. 5: Fair exchange: Cauvery water for city, in return for treated water for irrigation. In this win-win situtation Bengaluru could get more Cauvery water for drinking and Mandya and Mysore districts enough water for irrigation.

The plan thought up by a committee constituted by the government to increase its water supply, talks about setting up a treatment plant at the Byramangala reservoir to recycle storm water and non-potable water from the city for use in irrigation in the districts in the Cauvery belt and bring more of the river water to Bengaluru, say sources.

The committee is also considering bringing 10 to 12 tmc of Krishna water to the city. It hopes to divert the Kumaradhara and Nethravathi rivers towards Hemavathi for supply of 4 to 5 tmc to Bengaluru and construct a reservoir at Mekedat, where a hydro electric plant is being planned, for getting another 4 to 6 tmc of water for the city.

The 10-member committee headed by former BWSSB chairman B.N. Thyagaraja is expected to come out with a report on the water requirements of areas under the BDA until 2050. It is also expected to estimate the amount of water available to the city from existing sources like rain water and through water conservation and repairing of leaks in the distribution network.

Deccan Chronicle       06.01.2011

Silicon City circa 2050: Rich, hi-tech, and no water to drink?

Jan. 5: Can the allocation of 911 tmc ft of water by the Krishna tribunal to the state help Bengaluru?

Former chairman, BWSSB, B. N. Thyagaraja, who heads an expert committee to assess the water needs of the city for the next 40 years and look for alternate sources of water for it, says Bengaluru can hope to get at least 10 to 12 tmc ft of water from the Krishna river, but only as a last resort considering the distance and cost involved.

“Also around 10 tmc ft of water which flows into the sea from the Nethravathi and Kumaradhara rivers can be diverted to Hemavathi and brought to Tumkur via Gorur dam and then to Tippagondanahalli, giving the city around 4 to 5 tmc ft of water. There is also a proposal to construct a hydro-electric plant at Mekedatu and supply 4 to 6 tmc ft of the surplus water to Bengaluru,” he explains.

Bengaluru is clearly in need of more water as it has grown in size with the addition of new BBMP areas and the BWSSB able to meet the needs of hardly 40 to 45 per cent of the city. Although allocated 18 tmc ft of Cauvery water, Bengaluru is currently getting only 12 tmc ft and will receive another 6 tmc ft or 500 MLD after the Cauvery fourth stage, second phase is commissioned. But this is likely to happen only by March 2012 and not by October 2011 as promised. And by then the city’s population will have touched 8.02 million, leaving it still short of 400 MLD. To make matters worse, its groundwater has fallen to 900 ft and the storage of the TG Halli is depleting. The fast deteriorating situation prompted the BWSSB to form an expert committee to look for alternate sources of water to meet the city’s needs up to 2050.

The committee, which has been considering various alternatives like tapping water from the Krishna river, is keen on the rejuvenation of the Arkavathy and Kumudwathi rivers, as this will bring the city 25 MLD of water from the Hesargatta reservoir and 135 MLD from TG Halli.

It is also looking at recycling sewage to the city’s advantage. “The treated Vrishabhavathy valley water now reaches Byrmangla reservoir. After tertiary treatment, it can be given to Mandya and Maddur for irrigation and we can ask for more Cauvery water from KRS,” says Mr Thyagaraja.

Yet another way would be for the city to recycle its sewage and use it for non-potable purposes. Unfortunately, Bengaluru, which generates 720 MLD of sewage per day treats only 300 to 350 MLD of it. The BWSSB plans to set up 12 more STPs and introduce dual pipelines in new BDA areas, to make sure all the sewage is treated in future.

Worried that 408 MLD of water is going ‘unaccounted for’ as a result of the 100 year old pipelines running through the city, its many unauthorised connections, tampered meters and the misuse of public taps, the BWSSB has begun replacing pipelines over the last three years and plans to launch a scheme to reduce leaks in the system in Bengaluru south.

The committee hopes that repairing the leaks and increasing groundwater recharge through rain water harvesting, will help the city cope with the crisis till additional water is found for its use.