The Minor Irrigation Department and the Bangalore Water Supply and Sewerage Board (BWSSB) are passing the buck over the blunder of pumping untreated wastewater to Kolar.
What seems to have caused the inter-departmental tiff is the “lack of a barrier wall” to separate treated water from Bellandur Lake. A BWSSB official said that the Minor Irrigation Department has not built any concrete wall to prevent the Bellandur Lake water from entering their jack well. They have only placed sandbags at certain locations.
Officials said that since the water level of Bellandur Lake was higher than that of the jack well, every time the lake swells, untreated lake water would naturally enter the jack well. The Minor Irrigation Department may have been caught unawares and pumped untreated water to Kolar.
However, the Minor Irrigation Department in a letter to the government blamed BWSSB’s old sewage treatment plant (STP) for the mess. In the letter, it contends that the old 108 MLD capacity STP was defunct and made operational only recently. When 50 million litres of wastewater was treated, untreated water may have got mixed up and caused foam in the treated water.
An engineer from the Minor Irrigation Department said there was probably a backflow from Bellandur Lake which may have entered the jack well. This water may have been pumped to Kolar. However, the real reason is yet to be established. He said water at Lakshmisagara Lake in Kolar was not contaminated.
“On Friday, officials who visited the lake saw the presence of fish which means that it is not toxic yet. The water has been sent for testing and the results are awaited,” the engineer said. BWSSB also blamed the Minor Irrigation Department for not coordinating with it during the pumping of the water.
The Board official said that all their STPs were functioning well but the output of treated water varies every day. Their job is to only treat the wastewater and release it to the chlorine contact well. The department has constructed a jack well at that very point from where water is lifted and pumped through the pipeline to Kolar. Both officials however said that they would sit together and analyse the reason and rectify it in the coming days.