As per 2011 Census, static population of Kolkata was 44.96 lakh. As per CPHEEO guidelines, potable water demand of Kolkata is expected to reach close to 1,400 MLD requiring a generation capacity of around 1,660 MLD.

Kolkata Municipal Corporation (KMC) currently has Indira Gandhi Water Treatment Plant (Barrackpore) having generation capacity of 1,180 MLD (260 MGD), Watgunge Water Treatment Plant having generation capacity of 22.7 MLD (5 MGD), Jorabagan Water Treatment plant having generation capacity of 36.3 MLD (8 MGD) and Jai Hind Jal Prokolpo having generation capacity of 136.3 MLD (30 MGD). In addition, Garden Reach Water Works is having capacity of 839.4 MLD (185 MGD) and around 110 MLD is supplied by deep tube wells.

The objective of the Water Supply Department of KMC is to provide uninterrupted water supply to the residents of Kolkata. KMC also supplies water to adjacent Municipalities like Bidhannagar Municipal Corporation 90 MLD, Budge Budge Municipality 22.7 MLD.

With the above objective, in order to meet the potable water generation capacity of around 1,900 MLD in 2025, a 225 MLD (50 MGD) Water Treatment Plant has been started at Garden Reach Water Works. A 90 MLD (20 MGD) WTP is under construction at IGWTP.

Potable water supply to the city is carried out through seven zones based on hydraulic pattern and best engineering practices. They are Central, North, South, West, Jadavpur Unit, SSU, GRU, Joka and Tube Well (TW). Potable water is supplied through water pipe network spread over the City for ultimate utilization by Domestic, Industrial, Commercial and Institutional Consumers.

To improve water supply within KMC area, construction of local booster pumping stations are undertaken. Presently, there are 25 nos. of booster pumping stations in operation.