The attention captured by Bellandur lake, its froth and foam, and a perceived inability of the system to clean it can be a bit depressing. However, a visit to the lakes of North Bengaluru can cheer you up and make one think not all is lost. Thanks to the efforts of BDA, BBMP, BWSSB, elected representatives and citizen groups, many of them are protected well and some of them like Allalasandra, Yelahanka, Jakkur and Rachenahalli are brimming with water.
Coracles of fishermen go about casting nets, painted storks and pelican flock and roost on trees, walkers and joggers circumambulate the lakes and children run about happily in a wide expanse of clean air and lapping waters. There is much work to be done to improve things such as for example the ingress of untreated sewage in some lakes but overall things are good and point to a future for Bellandur itself.
All these tanks are interconnected. Attur lake flows into Puttenahalli which flows into Yelahanka, which joins Jakkur and thence to Rachenahalli, eventually becoming Dakshina Pinakini river.
Integrated Urban Water Management
The concept of IUWM is also in practice here. A 15 million litres per day (mld) waste-water treatment plant set up by the BWSSB treats sewage upstream of Jakkur. A large part of it will go to the power plant at Yelahanka and hopefully a chunk of it will also be allocated to Jakkur and Rachenahalli lakes.
This treated waste-water keeps the lakes full, recharges groundwater and then becomes available as well and borewell water for drinking purpose with some treatment. Similarly, rainwater is being harvested in the large storm-water drains which lead to the lake, managing floods too.
BEL (Bharat Electronics Limited) is building a 10 mld waste-water treatment plant at Doddabommasandra lake with monies from CSR, investing over ₹ 14 crore in a one-of-its- kind project in the country. This will replicate the Jakkur model. IUWM is the combined management of rainwater, piped water, groundwater and waste-water to fulfil ecological, social and functional purposes of a city. This is in practice in the upstream reaches of the Dakshina Pinakini in Bengaluru.
Moving forward
The city should now focus on the interconnectedness aspects of the tank eco-system and make sure that ‘Rajakaluves’, the stormwater drains, are opened up to the desired levels and developed ecologically and not just as concrete box drains.
The Centre for Ecological Sciences at the I.I.Sc. led by T.V. Ramachandra has provided the knowledge required to develop the Jakkur model of a constructed wetland and algal pond of reviving a lake ecosystem. Their assistance will be invaluable in developing the Rajakaluves too.
As citizen groups can only focus on a particular lake, a confederation of these groups from each of these lakes too must push the institutions of governance to complete the big picture of lake and water management in the city.
The network of sewage lines needs a lot of improvement and then their links to the WWTPs have to be established in a “zero sewage flow in storm drains’’ model. This has a bi g chance of success in this roughly 100 sq. km. watershed. This will only be possible through a citizen-monitored effort with the BWSSB. The lakes of North Bengaluru can be an exemplar for the city and for the country on how to manage water resources well.
If we had the Karnataka Lake Conservation and Development Authority it would have been easier and a distinct possibility.
Time to bring water wisdom at scale.
