Why a 135-year-old reservoir at Mumbai’s Malabar Hill is being rebuilt

Built in 1887, the Malabar Hill water reservoir is one of the first artificial water reservoirs built to meet the day-to-day water needs of Bombay. The reservoir is located at a hillock just beneath the surface of the Hanging Gardens.

The reservoir was built mainly with bricks and has an arch-type masonry construction. It can supply around 150 million litres per day (MLD). The BMC is planning to augment the capacity to 190 MLD. Water is now being pumped to the reservoir from the Vaitarna lake, one of the seven lakes that supply water to the Maharashtra capital.

The reconstruction plan

The decision to reconstruct the tank was taken following a 2019 structural audit. Civic officials said the reconstruction, using cement and concrete, would be completed in seven years.

The project has been divided into five phases. There are seven chambers inside the reservoir and each of them will be reconstructed in a phased manner. Before demolishing each chamber, water stored in it will be transferred into an adjoining chamber to ensure there is no interruption in water flow.

How will it help the city?

The Malabar Hill reservoir supplies water to the entire south Mumbai. The island city used to house most of the state capital’s population in the 19th century as the suburban belt was not suitable for human habitation.

The reservoir’s capacity was augmented first in 1925. However, not much restoration has taken place in the past 100 years.

“The primary objective is to ensure that the water shortage crisis is resolved. The population level and the overall demography of south Mumbai have changed drastically throughout the past decades, leading to a high demand in daily water supply. This project is being taken up by keeping in mind not just the present needs but also the future needs,” said a senior official of the water supply project department.

Since the reservoir is underneath the Hanging Gardens, the garden will be shut as long as the construction is ongoing, the official said.

“In the first phase the Gardens will not be shut, but after it is completed we will take a call on when to shut them. The BMC has all the required no-objection certificates for this project,” the official added.