MANDYA: Saturday marked a historic occasion in the annals of water supply in the city. A major step was taken towards reducing water wastage by ensuring Cauvery water is routed from the main reservoir in Malavalli in Mandya district through pipelines instead of the open canal procedure in place since 1973. Thanks to the commissioning of the pipelines on Saturday, the city now stands to save 25 million litres of water per day (MLD).
A Ravindra, Chief Engineer, Cauvery, Bangalore Water Supply and Sewerage Board (BWSSB), who headed the operation, told Express that water was lost on a daily basis due to evaporation, seepages and illegal usage of pumpsets along the open canal.
It was in 1953 that the 7-km canal was built by the then Mysuru Maharaja Nalwadi Krishnaraja Wodeyar to ensure Cauvery water could flow from Shiva Balancing Reservoir (SBR) to the Netkal Balancing Reservoir (NBR) through this path. “Then, it was intended only for harnessing power from it by the Shimsha Hydro Electric Power station which was supplied to KGF,” said S V Venkatesh, Executive Engineer at T K Halli.
However, after Bengaluru developed and demand for water soared, the commissioning of the Cauvery Water Supply Stage I in 1974, water flowed by gravity from SBR to NBR via this open canal, he said. It then goes through pipelines to T K Halli from where it is pumped to the city.
In preparation for this commissioning, BWSSB had closed and reopened one set of mammoth butterfly valves (named because they are shaped like wings of a butterfly), attached to the pipelines on July 28. The valves were being operated after a gap of 43 years.
Butterfly valves operated
Top BWSSB officials of the Cauvery Division reached T K Halli on Friday night to ensure a smooth transition. At 12.30 pm on Saturday, one butterfly valve which controls water flow to the open canal was closed and a new butterfly valve installed three years ago that will supply water to the pipelines was opened. “These supply water to the pipelines that were installed in connection with Cauvery I (1974) and II Stage (1984),” said Naresh B K, Assistant Executive Engineer at T K Halli.
“Following its successful commissioning, another old butterfly valve was closed and a new one opened at 1 pm,” he added. This will take care of the pipeline used for Cauvery Water Supply Stage-III (1992). The Cauvery IV Stage (2002) is already directly connected to NBR via pipelines.