The Brihanmumbai Municipal Corporation (BMC) has now decided to treat and clean nullah water, which mostly contains sewage and other kind of wastewater, to prevent the contaminated water from entering the sea and creeks. In the first phase, the BMC will spend Rs 83 crore for the purification of water from 26 nullahs for the next 5.5 years. But a civic activist says this project should not be treated as another experiment and should be undertaken only if it benefits the city.

The process

“According to National Green Tribunal guidelines, untreated sewage water should not flow into the sea or a natural water source. We will use in situ biological treatment (the use of aquatic plants, aquatic animals, and microbial remediation) for nullah water under the expert guidance of IIT, NEERI, and VJTI. This project will run for 5.5 years. It is a temporary project as we are in the process of connecting all sewers to sewage treatment plants,” said Ashok Mengade, chief engineer, Sewage Disposal Project, BMC.