2035 Vision for Sustainable and Equitable Water and Wastewater Management in Bangalore

Bengaluru city has experienced unprecedented growth in recent decades, from a population of 4 lakh in 1941 to 80 lakh in 2011 (96 lakhs for the Bangalore Urban district). In 2021, Bengaluru’s population is likely to be significantly more. If the city is to sustain growth and retain its position as a “global” high-tech city, it must provide its citizens with adequate, affordable, and equitable access to clean water, while meeting sustainability and environmental amenity requirements.

Many options to meet future demand for water have been proposed: expanding Cauvery supply, fixing pipeline leaks, promoting water-use efficiency, harvesting rainwater, rejuvenating urban lakes, using treated wastewater as well as building expensive inter-basin transfer schemes.

The goal of this study is to evaluate this range of options for water and wastewater management, so as provide input to civil society and policy makers as to how a “Sustainable, equitable water vision for Bengaluru” for Bangalore by 2035 may be implemented.

The following research questions will be explored:

  1. Urban Lakes: Can Bangalore’s lakes be managed to satisfy multiple competing objectives of water security, flood protection and environmental amenities?
  2. Equity and efficiency: : How much water can be made available by reducing unaccounted for water? Is it possible to reallocate some Cauvery water from “old Bangalore”, which receives the lion’s share, to the fast growing suburbs by shifting to dual supply and reducing outdoor water use?
  3. Recycled Wastewater: What are the comparative economics, technical considerations and institutional requirements of large centralized versus small decentralized approaches. What are the current barriers to large scale wastewater treatment and reuse/recycling?

For additional details please contact veena.srinivasan@atree.org

Urban Lakes

Urban lakes perform multiple functions –groundwater recharge, flood control, and environmental amenities. To understand how lakes are integrated with the larger water system in Bangalore, we have initiated detailed hydrological and water quality analyses in two lakes – Jakkur and Rachenahalli - in Bangalore, in collaboration with Biome Environmental Solutions and community groups like Jalaposhan. Only half of Jakkur Lake catchment is urban, almost 80% of Rachenahalli lake’s catchment is now urban. We have begun installing sensors in the lakes and at the inlets and outlets. Because the catchments of Jakkur and Rachenahalli lie along a continuum of urbanization, we hope to understand how the lake water balance and the contributions of treated sewage, untreated sewage and storm water changes within a year and over time.

We hope to model water quality and quantity to understand how urbanization affects the different functions of the lake. This will allow us to project the future state of the lakes over the next 30 years and suggest how they may best be managed to address Bangalore’s water needs.

Equity and Efficiency:

While BWSSB has also put in place a progressive tariff structure to ensure that the poorest are less impacted, and has made efforts through its social development unit, recent assessments show that the situation on the ground leaves a lot to be desired. Several pockets in the city are under-served by public water supply and estimated LPCD levels vary hugely, raising questions of inequities in distribution of water.

At present, we have begun assessing equity issues around Bangalore’s water at two levels:
At a macro-scale, we are working to analyze 2011 Housing Census Data from the Govt. of India. Initial analysis and mapping of types of water and sanitation sources used by households in Bangalore has been done using this dataset. The maps clearly show that while central Bangalore receives most of the imported piped water supply, the fast growing peri-urban suburbs get very little and are consequently groundwater dependent.
At the micro-scale, we are engaged in field-work in slums in Bangalore to understand concerns over inequity.

Wastewater recycling:

Wastewater recycling has been promoted as a possible solution to Bangalore’s extreme water scarcity problem. We address the research gaps in understanding the potential for wastewater recycling in Bangalore. The idea would be to come up with a more realistic 'supply' curve of recycled water. At the moment, most sewage in Bangalore is untreated. Moreover, there are different scales at which wastewater is currently being treated. Each of these scales of treatment entails different models of how wastewater recycling and use (WWRU) should be approached because the scale, ownership and regulatory structures are different. We have begun work on apartment-level micro sewage treatment plants using primary data shared by CDD and our own surveys of apartment level STPs.

Faculty

Senior Research Associates

  • Mrinalini Bakshi Sengupta

Research Associates

  • Tejas Kulkarni
  • Praveen Urs (WQ Lab Assistant)
  • Shruthi Patil

Interns

  • Pradeep Kuttawa
  • Chandan Gowda
  • Shashank R Palur​

Papers/Thesis

Reports

Articles in Popular Press