While Mumbai’s drinking water stock is still hovering at around 99 per cent, the water now available in the seven lakes will suffice for the entire dry season, against a daily water supply of between 3950 million litres per day (MLD) and 4100 MLD, according to the Brihanmumbai Municipal Corporation (BMC). The water stock will never reach 100 per cent, as each time the lakes are near full capacity, the BMC releases water from the lakes to maintain their holding capacity amid unpredictable rainfall patterns.
The water stock in Mumbai`s seven lakes touched the 99 per cent mark on September 19, with 14,33,121 million litres (ML) of water amounting to 99.02 per cent. The seven lakes — Upper Vaitarna, Modak Sagar, Tansa, Middle Vaitarna, and Bhatsa are located in the Thane and Nashik districts, while the Tulsi and Vihar are located in the Sanjay Gandhi National Park.
On September 29, the water stock in these seven lakes dropped from 99.46 per cent, or 14,39,588 ML to 97.57 per cent, or 14,12,132 ML within 24 hours despite over 300 mm of cumulative rainfall in the catchment area of these lakes. On Tuesday, the water stock in the seven lakes was at 99.04 per cent, amounting to 14,33,262 million litres of water, against the full capacity of 14,47,363 ML.
A senior civic official said, “When lake levels touch about 99 per cent and we see persistent rainfall, we have to open the gates of the dam. If the gates are closed, the water accumulated in the dams will cause flooding in neighbouring residential areas.”
Regarding the lake levels touching the numeric 100 per cent during the monsoon, the official said, “After the monsoon is over, BMC can close the dam gates. However, we draw about 4000 MLD of water. During monsoon, if lake levels are to touch the 100 per cent mark numerically, we will have to close all gates and stop drawing water from the lakes for daily supply.”
Water stock from Sept 1 till Oct 8
September 1
96.33% or 13,52,756 ML
September 15
98.49% or 14,25,574 ML
September 18
99.02% or 14,33,121 ML
September 30
98.38% or 14,23,857 ML
October 1
98.70% or 14,28,549 ML
October 8
99.03% or 14,23,262 ML
