Mumbai: After sitting on the drawing board for more than a decade, the BMC on Tuesday finally issued a Rs 3,000 crore tender to construct the 69-metre Gargai dam in Palghar district, along with a 1.6km, 2.2-metre diameter tunnel that will carry water to the Modak Sagar reservoir. The tunnel will be bored through the hill separating the two water bodies. Like Middle Vaitarna, Gargai will also be built as a roller compacted concrete (RCC) dam.Once commissioned, Gargai will add 440 million litres per day (MLD) to Mumbai’s water supply, making it the city’s first new reservoir since Middle Vaitarna became operational in 2014. The BMC is eyeing a 2029 completion, a year that coincides with the next Lok Sabha and assembly polls.Officials said Gargai was first approved as a source for Mumbai in a state govt GR issued in Nov 2013, after which preliminary engineering studies began. Gargai is a sub-tributary of the Vaitarna river. Although the execution period is set at four years, the BMC plans to finish the main dam structure in nine months, compared to the 15 months Middle Vaitarna took, despite that project being ranked the ninth fastest dam construction in the world.According to officials, the first year post-work order will go into securing permissions and creating infrastructure for relocating six affected villages. Dam construction is planned in the second year, followed by the installation of electrical systems in the third year. The project includes a 1,200-kilowatt hydropower unit, intended to offset the dam’s electricity costs. Middle Vaitarna, they said, took nearly 21 years from proposal to completion.However, the project comes with environmental implications. Around 3 lakh trees must be transplanted across neighbouring villages —two directly affected by the dam and four more required for tree relocation. Compensatory afforestation has been proposed across 658 hectares in Washim, Chandrapur, and Hingoli. All residents from affected villages will be shifted to Devali in Wada taluka, with full infrastructure planned at the new site, said officials. The project is still awaiting key clearances: Forest nod from the state and Centre, and National Board for Wildlife permission from the PMO.
