The Brihanmumbai Municipal Corporation (BMC) is spending at least Rs 240 crore over a span of three years to ensure that untreated sewage from Mumbai does not enter the sea. This is a stopgap measure as its Rs 28,000 crore sewage treatment plants (STP) project is slated for completion in 2026 and 2027. In compliance with directives from the National Green Tribunal (NGT), the BMC has decided to restart its bioremediation project for sewage from the wastewater treatment facilities (WWTFs) at Versova, Bhandup, Ghatkopar, and Malad.

This project, planned for the next year, will cost the civic body approximately Rs 100 crore, according to official information. In 2022, the BMC had similarly carried out bioremediation at these four WWTFs for a brief period of two years, at a cost of around Rs 140 crore. In November 2021, the National Green Tribunal imposed a penalty of approximately Rs 28 crore on the BMC for discharging untreated sewage into the sea around Mumbai.

Meanwhile, the BMC has planned the upgradation of all seven STPs in Mumbai at a total cost of approximately '28,000 crore. This will result in tertiary treatment of wastewater before it is discharged into the sea, providing treated water of a quality closest to that suitable for human consumption. A BMC official said, “While this upgradation is in progress, wastewater cannot be allowed to flow into the sea without treatment. Bioremediation is being undertaken by the sewage department as a temporary measure to address the issue.”