The city, which is already water deficient, will have a crisis on its hands in less than two decades with a shortfall of approximately 2,000 million litres per day (MLD) of potable and non-potable water for domestic and industrial use. In its Draft Revised Master Plan 2031, the Bangalore Development Authority (BDA) has reduced the projected shortfall to around 850 MLD by making a case for a Dual Pipeline System, which allows for water to be recycled, and conservation.
It also provides another solution: divert water from Linganamakki dam across Sharavathi river in Shivamogga district, over 430 km away, as proposed by the Tyagaraja Committee. However, this has been strongly contested by water conservation experts and farmers.
According to water conservationists, the BDA’s projections are on the conservative side. “The water woes of the city in 2031, with over 20.03 million people, will be much worse than what the draft RMP 2031 predicts,” said S. Vishwanath, a water conservation expert. While for most megacities, the per capita water demand is 200 LPCD (multiplied by the total population), which includes industrial water demand as well, the draft RMP considers 135 LPCD for domestic (multiplied by the total population) and 90 LPCD (multiplied by the working population, which is taken as 60% of the total population) for non-domestic — estimates that will derail projects.
The plan does not mention Rain Water Harvesting (RWH), a major lacuna, even as the BWSSB has begun aggressively pursuing RWH even for old buildings to reduce the per capita demand.
Dual piping
The draft plan relies on dual piping, for all new houses and the future population, through which recycled water will be supplied for all non-potable purposes. The goal is to harness 865 MLD of recycled water, and the excess can be used to recharge lakes and thereby ground water levels.
With these measures, the BDA predicts that the shortfall will be reduced from about 2,000 MLD to 850 MLD, which can be met from the ground water table. But the city’s reliance on ground water will be 27% more than what it is today.
No mention of STP
Even as the draft plan heavily relies on recycled water for demand reduction, it is silent on the sewerage network and Sewage Treatment Plant (STP) infrastructure needed by 2031. The draft plan simply recommends an expansion of BWSSB services for the entire Bengaluru Metropolitan Area (BMA).
BDA hits the right notes in waste management
The Solid Waste Management (SWM) strategy seems to be one area where the Draft RMP 2031 makes all the right noises and adoption of best practices.
On a positive note, the draft plan expands the SWM strategy – segregation of waste at source, separation of bulk waste – to the surrounding villages in the Bengaluru Metropolitan Area (BMA) as well.
There are two opposing views on waste management: one argues that composting of wet waste has been a failure and advocates complete shift to Waste-to-Energy plants while others see them as polluting and non-viable.
The plan attempts to strike a balance by proposing eight Integrated Waste Processing Plants in addition to upgrading the nine running today. These plants will incorporate both composting and WtE technology.
Organic waste is first composted, but the RDF it generates, along with other combustible non-biodegradable waste, will be incinerated to produce power using WtE technology, the plan suggests.
N.S. Ramakanth, member, SWM Expert Committee, says this is an acceptable strategy.
The draft plan also incorporates the recent High Court direction for implementation of a micro plan and decentralised processing of waste. It recommends 12 bio-methanisation plants of five TPD capacity and 85 Organic Waste Converters of 1 TPD capacity for the entire BMA.
However, the draft plan has been criticised for what many see as ‘token’ recommendations.
Ramprasad, an SWM activist, said that in a decentralisation model, every ward within BBMP limits and their equivalent outside must have smaller Organic Waste Converters, and that the proposed 85 will not be sufficient even for the BBMP area. He estimates that the city will need 300 converters by 2031.
Also, the plan does not stress on separating various streams of waste, like construction debris, animal waste, sanitary waste and other hazardous waste, and doesn’t provide strategies for processing such waste.
