Mumbai: BMC plans to integrate the city’s first seawater desalination plant at Manori with Mumbai’s existing water distribution network through a 7.2km underground tunnel to Charkop and further to Mahavir Nagar in Kandivli.A proposal seeking approval to award the contract at Rs 2,241.3 crore to Afcons Infrastructure Ltd for its design, construction and operation as well as for associated infrastructure is scheduled to be placed before the civic standing committee on Wednesday. The water tunnel alone will account for more than half the estimated cost of the Rs 4,077-crore desalination project at Manori.BMC hopes to begin construction next month and is targeting a timeline of 45 months.Afcons Infrastructure had emerged as the lowest bidder after negotiations, reducing its original quote to Rs 1,575 crore for core works. The total outlay for the tunnel includes GST, contingencies, operation and maintenance and other components.The proposed tunnel will run 4.6km from Manori to MNP Udyan at Charkop and another 2.6km to Mahavir Nagar. It will be excavated at a depth of 104-128m using two tunnel boring machines operating simultaneously from Manori and Mahavir Nagar.“The project includes construction of three deep shafts at Manori, Charkop and Mahavir Nagar, a pumping station at Manori designed for an ultimate capacity of 400 million litres per day (MLD), transmission mains, product water tanks, valve chambers, SCADA integration (for monitoring and controlling processes) and other allied infrastructure. While the pumping station will ultimately be capable of handling 400 MLD, mechanical and electrical systems for the first phase will initially be installed for 200 MLD, matching the capacity of the first phase of the desalination plant,” said an official.A senior civic official said the tunnel will allow nearly 190 MLD of water currently supplied from Bhandup to be reallocated to other parts of the city, improving the overall efficiency of Mumbai’s water supply network. “A very small quantum of water is currently required around Manori. Therefore, most of the desalinated water will be conveyed to the western suburbs through the existing network.”BMC has issued a public notice inviting objections from citizens and owners of properties on the tunnel’s alignment.Mumbai’s current daily water demand is around 4,600 MLD against an available supply of about 4,100 MLD. The desalination project has been conceived to bridge this gap and reduce the city’s dependence on rainfall-fed lakes, which have become increasingly vulnerable to erratic monsoons and climate change.
