The Brihanmumbai Municipal Corporation (BMC) has approved a Rs 2,241.3-crore project to construct an underground tunnel that will connect Mumbai’s first seawater desalination plant at Manori with the city’s existing water distribution network. Although the proposal received the standing committee’s approval, several corporators raised concerns over water quality, the tendering process and technical aspects of the project during the discussion.
The contract has been awarded to Afcons Infrastructure Ltd for the design, construction, operation and maintenance of the 7.2-km tunnel and related infrastructure. Construction is expected to commence next month and be completed within 45 months, with the project scheduled to become operational by December 2029.
The tunnel will serve as a key transmission link between the upcoming desalination plant at Manori and Mumbai’s water supply system. It will run from Manori to Charkop and connect to the existing Mahavir Nagar shaft in Kandivli, passing largely beneath Gorai Creek.
Designed with a finished diameter of 3.2 metres, the tunnel will initially transport 200 million litres per day (MLD) of desalinated water, while its infrastructure has been planned to accommodate an eventual capacity of 400 MLD. BMC officials said two tunnel boring machines (TBMs) will be deployed simultaneously to accelerate construction.
During the meeting, Shiv Sena (UBT) corporator Yashodhar Phanse questioned whether desalinated water would match the quality of water supplied from the Bhandup Water Treatment Complex. “We are in favour of the project, but our staff should also be trained to execute such specialised works,” he said.
Congress corporator Ashraf Azmi questioned the decision to issue separate tenders for the desalination plant and the tunnel. “Also why did the BMC keep 16% as contingency fund for the project?,” said Azmi.
Congress corporator Tulip Miranda also expressed concerns over blending desalinated water with treated lake water. “People have raised concerns about hair dryness and breakage because of minerals and chlorine in desalinated water. What steps will the BMC take to ensure there is no impact on citizens to whom this water is supplied?” she asked.
Responding to the concerns, Additional Municipal Commissioner Abhijit Bangar said the quality of desalinated water would be brought in line with water supplied from the Bhandup Water Treatment Complex before entering the city’s distribution network.
“The tunnel is technically complex. Of the 7.2 km length, about 5.1 km will have RCC lining while the remaining stretch will have mild steel lining with M30 grade concrete protection. Strict penalties have been built into the contract for any leakage,” Bangar said.
He added that the 16% contingency provision accounts for annual price escalation during construction and follows industry standards. The tunnel has also been designed to support Mumbai’s long-term water demand by accommodating a future capacity of 400 MLD.
Source: The Times of India
