

BENGALURU: Bengaluru can significantly ease its recurring water shortages by recycling up to 60% of the waste water generated within the city, according to a new international study.
However, poor governance, weak enforcement and operational failures are preventing the city from unlocking its full potential, the study added.
The study, conducted by researchers from the Swiss Federal Institute of Aquatic Science and Technology (Eawag), Georgetown University, USA, and Bengaluru-based Water, Environment, Land and Livelihoods (WELL) Labs, estimates that between 473 million litres and 1,187 million litres of waste water generated daily (MLD) could be safely reused for non-potable purposes such as toilet flushing, landscaping, construction and cooling systems.
Researchers found that despite Bengaluru having more than 3,000 decentralised waste water treatment and reuse systems (DWTRS) – the highest concentration in the world – only about 47 MLD of treated waste water is currently being reused. The team reviewed two decades of water policies, interviewed government officials, experts and residents, and inspected 22 decentralised sewage treatment plants, mostly located in apartment complexes.
The findings revealed widespread operational deficiencies. “More than 80% of the inspected plants suffered from compliance issues, producing treated water with noticeable colour, odour and turbidity. Most facilities lacked trained operators, with security guards and housekeeping staff often managing complex treatment systems. More than 80% of the plants also failed to reuse treated water for all non-potable purposes mandated under existing regulations,” the study read.
The researchers said fragmented governance and poor coordination among multiple agencies, including water supply, environmental and urban development authorities, have hampered effective implementation.
The study also noted that heavily subsidised piped water and virtually free groundwater extraction have reduced incentives for apartment complexes to invest in waste water recycling systems.