Aiming for the im-situ treatment of sewage in nullahs in the city, the BRIHANMUMBAI Municipal Corporation (BMC) has tied up with the Indian Institute of Technology (IIT-B). It will prevent coastal pollution due to sewage from 25 nullahs in Bandra, Andheri, Goregaon, Kandivali, Borivali, and Dahisar from flowing untreated into the sea or creeks.
By using a seven-stage process with the help of screens, gates, silt traps, curtains of coconut fibres for filtration, and disinfection using sodium hypochlorite, without the requirement of additional space sewage in nullahs is treated by IIT-B’s N-Treat technology. The project is a temporary and short-term measure to comply with the National Green Tribunal (NGT) that directed the civic body in 2019 to permanently check the flow of sewage from nullahs and their tributaries into the sea and creeks in Mumbai.
Earlier in March, BMC sought a consultant to prepare a detailed project report (DPR) to check the discharge of sewage from major nullahs and their tributaries and find permanent solutions for preventing such pollution. “Multiple civic departments are working on the issue. While a permanent solution is being prepared to check sewage discharge into the nullahs and subsequently into the sea, we are working to handle the present pollution in the nullahs.” said a senior civic officer.
The project is estimated to cost BMC Rs 82 crore and will be taken up in stages over the next five years. The official quoted above said, “BMC approached IIT-B for a solution for the treatment of sewage in nullahs. IIT submitted a detailed proposal with the use of N-Treat technology. This is the first time it is being used by the civic body. Tenders have been floated to appoint a contractor for the project.”
Of the 25 nullahs selected for the project, five are in Bandra and Santacruz area: Rahul Nagar nullah, Boran nullah, Behrampada nullah, and P&T nullah in Santacruz and on Link Road; seven are in Andheri – Milan Subway nullah, Cargo Complex nullah 1 and 2, Koldongri nullah, Abhishek nullah, Malpadongri nullah, and Mogra nullah; six are around Malad and Goregaon – Dnyaneshwar Nagar nullah, Krishna Nagar nullah, Chincholi nullah, Piramal nullah, MHB Malad nullah, and Paptarshi nullah; and the remaining are north of Kandivali – Janupada, Pancholi, Kumbharkala, Kora Kendra, Tawdem Tare Compound, and Avdut nullahs.
Stalin Dayanand, from NGO Vanashakti which approached NGT in 2017 for coastal pollution due to the discharge of untreated sewage into the sea, said, “What BMC is doing is the bare minimum. It is not enough but it is a start. The civic body is doing today what was told to it in 2018. Moreover, all its activities and projects are designed to look expensive, whereas simple measures are enough to achieve the same effect.”