India, July 23 -- The seven sewage treatment plants (STPs) being built across the city will turn grey into gold. The civic administration says the plants, at various stages of construction, will save millions of litres of potable water a day.

The grey water produced from sewage treatment will be used in tertiary activities, such as deep cleaning of roads and watering public gardens, thus saving potable water, which currently meets these needs. According to Rajesh Tamhane, deputy municipal commissioner (environment), the total savings would be 1,200 MLD of potable water a day from all seven plants.

Improving the quality of sewage discharged into the Arabian Sea will also enhance the health of the marine ecosystem, according to the Brihan...