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.
Background
Mumbai’s sewer network was designed to use natural gradients for sewage flow. To prevent blockages from methane build-up, vent shafts were placed every 100 to 150 metres along the drains. Traditionally, these tower-like structures were made of reinforced concrete and served only one function: to release compressed gas.
The new project
Under the pilot, 120 new shafts have been installed across the city. Each costs around R80,000. If successful, the BMC plans to replace all existing shafts with this upgraded version.
“These shafts not only release methane but also curb the odour. The old RCC shafts are in poor condition and lack odour-control mechanisms. The new design makes cleaning easier and ensures better air quality in neighbourhoods,” an official from the sewage operations department said.
Rs 80,000
Cost of each shaft
