Sewage to soil drains for two more years in Bengaluru

BENGALURU:Despite coming under pressure from all sides, the city's water supply utility cannot keep sewage away from storm water drains for another two years. Reason: A series of pipeline replacement projects have overshot their deadlines.

Having missed the 2014 and 2015 deadlines,the 495 crore Environmental Action Plan-B-under which 76 km of main sewer lines are to be replaced-is expected to be ready only in 2016 or 2017. The project is also expected to increase the city's sewage treatment capacity by 150 million litres per day (MLD).

Bangalore Water Supply and Sewerage Board engineer-in chief T Venkatraju, however, was quick to add: “Plan B (work) may extend up to the end of 2016, or even 2017. But once it is complete,we will be able to treat more sewage water in addition to our existing 721 MLD,so that treated water can be let out into water bodies.“

According to the utility,over three-fourth of the 1,350 MLD water supplied to Bengaluru becomes sewage,collected through 3,300 km of small-diameter sewage pipes. This water is conveyed to sewage treatment plants through 300 km of higher diameter pipes, most of which were laid 50-60 years back.

The utility has already replaced 33 km of sewage lines under the Environmental Action Plan-A, and is preparing a detailed project report to rehabilitate 74 km of sewage network under the Environmental Action Plan-C. Another project to ensure zerosewage flow to Hebbal and Nagavara lakes by replacing 19 km of pipeline is due to be completed next month. For mer BWSSB chairperson BN Thyagaraja said that if all the projects achieved desired results, the menace of sewage polluting lakes can be stopped.

“I have suggested having decentralised STPs so that treatment is localised and cost is reduced. In fact, each ward should have a treatment plant,“ said TV Ramachandra from Centre for Ecological Sciences at the Indian Institute of Science. “Big proposals come with their own agendas, but authorities should really go step-by-step,“ he said.