Phase-wise reconstruction of Malabar Hill reservoir may lead to leakages, says expert | Mumbai news - Hindustan Times

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The reconstruction of the 140-year-old Malabar Hill reservoir under Hanging Garden should be taken up by the Brihanmumbai Municipal Corporation (BMC) in one go as there is a probability that uncontrolled leakages might reoccur leading to a landslide or flash flood in low-lying areas, a structural consultant has said. Full Sticky Pvc Liner Roll

Phase-wise reconstruction of Malabar Hill reservoir may lead to leakages, says expert | Mumbai news - Hindustan Times

Shashank Mehendale from Shashank Mehendale and Associates, one of the experts appointed by BMC to opine on the feasibility of the project, has made this observation in a report submitted to the civic body.

“A study of the reservoir’s history has revealed that after its construction the reservoir had severe leakage issues. The amount of money spent on waterproofing was significant. Initially, asphalt lining was done. Even when there was still a loss of two million litres per day (MLD), major work of guniting/shortening was taken up in 1937,” the report said. HT has a copy of it.

The report further said that the nature of the reservoir where masonry walls were mainly the retention walls needed an explicit waterproofing layer to retain water.

“This waterproofing membrane - be it asphalt or granite - is relatively thin and susceptible to cracks and can fail even with slightest movement or vibrations. Thus, carrying out major disconnection and demolition of contiguous masonry structure, excavation by breaking, and cutting rock in close proximity of the reservoir foundation envisaged in the proposed phase programme can damage the waterproofing of the reservoir and may in turn cause leakages. This may result in a loss of a large quantity of water and a portion of the reservoir/whole reservoir being unusable. It may be prudent to take the entire reservoir in one go. Accidental profuse leakages may also trigger landslides or flash floods in low-lying areas,” Mehendale said in his report.

Mehendale stressed the need to create a minimum capacity permanent reservoir at a suitable alternative location without disturbing the current functional reservoir.

“Thereafter, the water supply can be diverted to the newly built reservoir. Only then one can take up reconstruction of the entire Malabar Hill reservoir in one go. This will also reduce the number of joints in the new tank and hence will reduce chances of leakages in anticipated 100-year service life,” the report said.

Indrani Malkani, a veteran activist and a local resident, said that in 2000 when citizens were going around and checking on the overgrown vegetation around the land that belonged to the Central Public Works Department, they first learnt of a leakage from the reservoir.

“Also, in 2018, the storm water drain was to be constructed which was below the viewing deck in the chowpatty. Our committee was told there was a leakage from the reservoir. A leakage weakens the structure and water finds its own way as one cannot control water,” she added.

Phase-wise reconstruction of Malabar Hill reservoir may lead to leakages, says expert | Mumbai news - Hindustan Times

Pool Ruber Liner Before taking up the reconstruction work, BMC plans to build a 90-MLD tank at a site behind the garden so that water supply to south Mumbai is not affected. The current reservoir has a capacity of 147 MLD and BMC’s waterworks department has decided to augment this to 191 MLD.