To address the annual water shortages and eliminate water cuts, the Brihanmumbai Municipal Corporation (BMC) has been exploring options for augmenting water resources. Two potential solutions emerged: desalination of seawater and the development of the Gargai water resources into a dam, supplying water to the Modak Sagar Lake.
Preventing Tree Cutting for Gargai Dam
The BMC's study indicated that the construction of the Gargai dam would require the felling of approximately 2.5 lakh trees. With a focus on preserving the environment, the BMC has decided to prioritise the establishment of seawater desalination plants instead. The tendering process for the desalination project is expected to commence within the next two to three months.
“The study of BMC shows that around 2.5 lakh trees need to be cut to construct Gargai dam and we want to save those trees. Therefore, We have given first preference to the desalination of seawater plants. Tenders for the desalination project will be floated in the next two to three months
“On the other hand, a company has been selected for the construction of Gargai dam and a tender document is also being prepared. Thereafter, the permission of the state government will be taken and then work will begin. The estimated time of construction of Gargai dam is three years,” Additional Municipal Commissioner, (Project) P Velrasu said.
Progress on Gargai Dam Construction
Concurrently, the BMC has selected a company for the construction of the Gargai dam, and preparations for the tender document are underway. Once the state government grants permission, construction work on the Gargai dam is scheduled to begin. The estimated timeframe for completing the dam is three years.
Current Water Resources and Supply
To cater to the water needs of Mumbai, the city relies on seven dams: Upper Vaitarna, Modak Sagar, Tansa, Madhya Vaitarna, Bhatsa, Vihar, and Tulsi. These lakes collectively hold 14 lakh 47 million litres of water. The BMC supplies 3850 million litres of potable water daily, while the actual demand stands at 4200 million litres per day. The Hydraulic department of the BMC regularly assesses water stocks and formulates water management plans for the year.
Annual Water Cuts and Reserve Water Usage
During May and June, the BMC traditionally seeks permission from the state government to utilize reserve water stock from the Bhatsa and Upper Vaitarna lakes. Last year, all lake levels dipped by 11%, prompting the BMC to implement a 10% water cut in Mumbai. However, heavy rainfall in July led to the withdrawal of water cuts after 12 days. This year, the city is once again at risk of facing water cuts.