BMC project to ensure city gets water from Koyna dam

In the light of the city’s growing water needs, the Brihanmumbai Municipal Corporation (BMC) has decided to concentrate on major water projects, which can provide long-term solutions to Mumbai’s water shortage, instead of going for smaller ones.

A few years ago, the BMC had ambitiously proposed to the state government to draw water from phase II of the Koyna dam in Chiplun (Ratnagiri district), about 300km from Mumbai. The state government’s water supply and sanitation department has now decided to undertake the project on a build-and-operate basis. It had invited interest bids to which 12 companies have responded.

The proposal to draw water from the Koyna dam may give 1,69,800 million litres of water on an annual basis to the city as well surrounding regions like Thane and Raigad. According to the state government’s plan, the project would cost about Rs40,000 crore.

According to officials of the water supply and sanitation department, the government discharges about 1,69,800 million litres of water from the Koyna dam to the Vashishthi river at Chiplun after generating power.

There is no scope to divert the water to nearby parts for irrigation or other purposes because of the area’s topography. The Maharashtra Industrial Development Corporation (MIDC) lifts water from the river for industrial purposes at the Chiplun MIDC.

The city's water requirement is 4,250mld. However, it receives only 3,350mld. Six lakes in and around Mumbai supply water to the city.

Upper Vaitarna supplies 630mld, Modaksagar 455mld, Tansa 407mld, Vihar 110mld, Tulsi 18mld and Bhatsa 1,900mld. However, 20% of the supply (or 600mld) is lost due to leakages and theft. Moreover, the supply from Vihar and Tulsi lakes is mainly used for industrial purposes.

The BMC has further decided to concentrate on the Damanganga-Pinjal water project (close to Daman) in coordination with the state government. The project is expected to bring 1,200mld water to the city. The BMC had planned it with an eye on the city’s water needs in 2050.

The Chitale Committee, appointed by the state government in 1993, had suggested four major projects to take care of Mumbai’s water supply needs: Middle Vaitarna, Gargai, Pinjal and Kalu.

The Damanganga-Pinjal project was proposed by the National Water Development Agency. The Maharashtra and Gujarat governments and the Union ministry of water resources had signed a memorandum of understanding to this end last year.