No respite for rivers from Bengaluru sewage till 2024

A part of Bengaluru’s sewage will continue to run into river valleys and lakes till 2024, according to the latest deadline set by the BWSSB for construction of sewage treatment plants (STPs), including three which should have been completed by 2020.

The latest report submitted by the state government to an expert committee shows that the Bangalore Water Supply and Sewerage Board (BWSSB) has a long way to go before setting up infrastructure for processing all the waste water generated by the city.

The committee set up by the National Green Tribunal has been looking into the matter of pollution of river stretches in general and the BWSSB has been pulled up several times over the last three years for failing to comply with the NGT orders.

The BWSSB was directed to ensure no sewage flows into lakes and river valleys by September 2020.

The BWSSB estimates that Bengaluru produces about 1,440 million litres (mld) of sewage a day of which about 1,000 mld was being treated. In addition to this, officials face the challenge of treating 120 mld waste water from the 110 villages added to BBMP about 15 years ago.

Of the 33 STPs functioning, several are underutilised. For example, the Hebbal STP with a capacity to treat 100 mld, processes only 49.01 mld. The two STPs in KR Puram process 16.6 mld against the capacity of 40 mld. At Kengeri, the 180-mld capacity STP is processing only 10 mld.

BWSSB chief engineer for Waste Water Management B C Gangadhar said work was on to complete the construction of STPs.

“Besides the Covid-19 pandemic, we had to upgrade the STPs to meet the quality standards set by the NGT. We will meet the revised deadlines for the city,” he said.

An engineer who is looking into the STPs planned in 110 villages said work on the underground drainage as well as the STPs will be completed by 2024.

“As per the rule, we won’t process sewage from commercial establishments spread over 2,000 sq ft and apartments with more than 20 housing units. They have to process their waste water in situ,” he said.

To a question, however, he agreed that the 120 mld figure was an underestimation. “The rapid urbanisation of the outskirts needs to be stopped. A rule should be introduced to ensure no layouts are built unless a treatment mechanism is established on the site. Otherwise, our STPs will not be able to catch up with the sewage output,” he added.

Retired BWSSB chief engineer M N Thippeswamy said countries across the world see treated water as black gold. “We don’t know what we are losing. Cities across the world are nearing 100% utilisation of treated water, even for potable purpose. We are spending thousands of crores to bring water from far away sources and similar amount of money to pump them away from the city,” he said.