Bengaluru: The Bangalore Water Supply and Sewerage Board (BWSSB) has invited tenders for the construction of nine new Sewage Treatment Plants (STPs) across the city, which together will treat 535 million litres per day (MLD) of sewage. Once completed, Bengaluru’s total sewage treatment capacity will rise to 1,883.5 MLD, reports The Hindu.
Despite the addition, the city will still fall short of its estimated requirement of over 2,740 MLD. Bengaluru currently generates around 2,120 MLD of sewage daily, and this volume is expected to increase by another 620 MLD following the implementation of the Cauvery Stage V project.
BWSSB Chairman V. Ramprasath Manohar said that six of the new STPs will generate electricity from biogas, while treated sludge will be converted into manure and sold to generate additional revenue. “These plants will also include odour control units to reduce foul smells, ensuring a cleaner and more community-friendly operation,” he said.
Power Generation from Biogas
The six larger STPs—each with a processing capacity of 50 MLD or more—will produce up to 4 MW of power from biogas. This marks a major technological advancement, with only the Hebbal and Vrishabhavathi Valley STPs currently using this method. The power generated will be used to run the plants, designed so that at least half of their energy needs are met through biogas. Officials said this will reduce electricity expenses and dependence on the Bescom power grid.
Eco-Friendly Technology
The new plants will feature advanced anaerobic systems such as A2O Technology, coupled with tertiary treatment using disc filters—an environmentally friendly alternative to traditional sand or multimedia filters. These technologies will help the plants meet updated discharge standards set by the Central Pollution Control Board and the National Green Tribunal.
The sludge generated will be processed into safe, nutrient-rich manure, which the BWSSB plans to sell commercially. “This approach will ensure both environmental compliance and revenue generation,” officials added.
Project Cost and Funding
The total cost of the nine STPs is estimated at ₹2,071.21 crore. Funding will be shared between the State government and BWSSB, each contributing 25% of the cost, while the remaining amount will be covered through loans. The board is set to issue an Expression of Interest (EoI) to financial institutions soon to secure funding for the project.
Once operational, these new STPs are expected to play a key role in improving Bengaluru’s wastewater management, promoting resource recovery, and reducing the environmental footprint of sewage treatment.
