In a slightly suffocating, tube light-lit passageway, some 70 ft below the seabed, more than 200 workers and nine engineers have been busily burrowing since October 2007.
The excavation, of a part of the tunnel, from Malabar Hill to SK Patil Garden, is complete, 15 days before scheduled time. The plastering is still to be done.
A pipe supplies life-giving oxygen to the men inside.
Once the entire project is complete — in January 2011, as per plan — south Mumbai will get an additional 60 million litres per day (MLD).
The Brihanmumbai Municipal Corporation currently supplies 240 MLD water to south Mumbai areas including Malabar Hill and Nariman Point. But a lot of that is wasted.
In many parts of Colaba, the water is either in short supply or low in pressure. In another 18 months, that may change.
The 1.85 km excavation work from Khilachand Garden, Malabar Hill to S K Patil Garden (Girgaon) is over. The next phase from Cross Maidan to SK Patil Garden will start soon and is expected to be complete within six months.
A 240 MLD reservoir supplies water to A ward (Fort, Churchgate, Colaba, Nariman Point), C ward (Marine Lines, Girgaum) and D ward (Marine Drive, Malabar Hill, Napean Sea Road, Peddar Road and Nana Chowk).
While water shortage has affected residents of all these areas, the worst hit are those living in old buildings without suction tanks for storing water.
The tunnel is replacing the 80-year-old water pipelines. “After completing this ambitious project, 20-25 per cent of water now wasted will go into south Mumbai houses,” said Mayor Shubha Raul.
Rakesh Katoch, project manager of Pratibha Industries, contractors of the project, said: “We are doing tunnel work below the seabed for the first time and it’s a challenging job, but we are confident we will complete the project on time.”