Bengaluru's growing water needs

Water enters the city silently every day, all 1,400 million litres of it, then leaves the city silently. This unrecognised feat of engineering that pumps water to a distance of 95 kilometre and then up 300 metres from the Cauvery river, is what keeps the economic engine that is the city of Bengaluru pumping and alive. The livelihoods and the health of its inhabitants depend completely on these waters.

The fiscal health as well as the human resource capabilities of the Bangalore Water Supply and Sewerage Board (BWSSB) also deserves much more attention than it gets. Water tariffs have to reflect the price of its safe collection and treatment after use in the millions of households spread across the city.

The city takes approximately 6.67% of the allocated share of the Cauvery waters to Karnataka but supports about 40% of its population in the basin. After the water is used in the city, a substantial portion of it is treated and sent to the drought-prone districts surrounding it. This used water will fill lakes, recharge groundwater and become available to farmers for irrigation. Eventually, when fully complete, the city can be seen as a generator of water resources for secondary use rather than a net consumer of water.

Also Read | Way out of Bengaluru'srecurring water crisis

Wastewater treatment

The city can learn from Chennai, where wastewater treatment plants generate energy and tertiary treated water fills lakes and is reused to meet potable water needs for Chennai.

The project to refill Hesaraghatta and Thippagondanahalli with tertiary treated wastewater from the Vrishabhavathi valley should be revived and implemented.

A continued focus on improving the sewage network and collecting every drop of sewage without allowing it to flow in storm drains is important. This sewage, when collected and treated, is useful to the need of farmers, fishermen and the city itself.

Apartments in the peripheral suburbs of the city are doing good work with reference to water use. IOT (Internet of things) based smart water metres or even normal water metres, when implemented with volumetric pricing of water, have been shown to substantially reduce water consumption in flats by as much as 40% to 50%. This reduced consumption of water means a reduced burden on wastewater treatment plants in these apartments leading to less dependency on water tankers and thus on borewells. The water utility by-laws now require a set of more than four apartments to have their own water metres too. This is a good measure.

Also Read | Many ways to join the fight against the water crisis

With the accessibility of the piped connection to all households and with a target usage of 100 litres per capita per day, the city will do well to report progress and milestones at both ward level and the city level itself, preferably every month on a dashboard.

Even the partial revival of lakes and good rains of the last year have substantially brought up groundwater tables. Dry borewells are recharged and dire predictions of the city running out of groundwater by 2020 have proved false. More attention to rainwater harvesting and lake revival can mitigate urban floods.

While individual action of rainwater harvesting and groundwater recharge is increasing, better institutional regulation and management of groundwater is also the need of the hour.

A new project likely to be finished by next year will bring in 775 million litres per day to the city. With this, the water shortage at a city scale should be overcome. Transparency is crucial to a good water supply system.

(The writer is a water conservation expert based in Bengaluru)

Watch the latest DH Videos here: