The Brihanmumbai Municipal Corporation (BMC) has launched a pilot project across Mumbai to replace old, dilapidated sewer vent shafts with new technology designed to control odour caused by methane build-up in underground drains. Earlier, vent shafts were built taller than the two- or three-storey buildings of old Mumbai so that the released gas would not affect residents. However, with the city now dotted with high-rises, these structures often fail to keep the stench away, a senior civic official explained.

The newly installed shafts are fitted with odour-control mechanisms and are shorter in height, making them easier to clean and maintain.