Mumbai Retains 10% Water Supply Cut Despite Reservoirs Reaching Nearly 70% Capacity as BMC Prioritises Long-Term Water Security

Mumbai's water reservoirs have recovered to nearly 70% capacity after heavy monsoon rainfall, with four lakes overflowing. Despite the improvement, the Brihanmumbai Municipal Corporation has retained the 10% water supply cut, stating that all seven reservoirs must reach full capacity by September 30 to ensure long-term drinking water security.

Mumbai's water reservoirs have staged a remarkable recovery after weeks of heavy monsoon rainfall, with four of the city's seven drinking water lakes already overflowing and total water storage nearing 70% of its full capacity. Despite the encouraging improvement, the Brihanmumbai Municipal Corporation (BMC) has decided not to withdraw the 10% water supply cut imposed earlier this year, maintaining that it is too early to conclude that the city's water concerns have ended.

The civic administration has emphasised that its primary objective is to ensure an uninterrupted drinking water supply throughout the year rather than making decisions based solely on current rainfall. The BMC had announced a 10% reduction in Mumbai's water supply on May 11, with the restrictions coming into effect from May 15 after water levels across the city's seven reservoirs dropped to critically low levels.

Although reservoir levels have improved significantly following continuous monsoon rainfall, the city's total water storage remains below the 86.88% recorded during the corresponding period last year. Officials believe that the current recovery, while encouraging, is not sufficient to guarantee water security for the months ahead.

According to the BMC, the decision to continue the water cut is based on long-term planning rather than present reservoir conditions. Additional Municipal Commissioner Abhijit Bangar, quoted by CNBC, said that the civic body will consider withdrawing the 10% water supply reduction only if all seven reservoirs reach 100% of their storage capacity by September 30.

Officials stated that although July has witnessed abundant rainfall, the performance of the monsoon during August and September remains uncertain. They cautioned that if rainfall weakens during the remaining monsoon months, reservoirs may not reach full capacity, increasing the possibility of water shortages during the next summer.

The precautionary approach follows a period of severe concern earlier this year. At one stage in June, the combined water storage across Mumbai's seven reservoirs fell below 10%, raising fears over whether sufficient drinking water would be available until the arrival of the monsoon. Weather forecasts at the time also indicated the possibility of a weaker-than-normal monsoon, prompting the BMC to introduce water conservation measures.

In addition to reducing the city's water supply by 10%, the civic body also prohibited the use of municipal water for filling swimming pools, according to a report by Moneycontrol.

Heavy rainfall over the past several weeks has substantially improved reservoir levels across the Mumbai Metropolitan Region. As of Thursday morning, the city's seven reservoirs collectively held 10,09,432 million litres of water, representing 69.74% of their total storage capacity. Water reserves increased by nearly eight percentage points within just 24 hours due to intense monsoon showers.

Among the seven reservoirs, Tulsi, Vihar, Tansa and Modak Sagar have already started overflowing, reflecting the impact of sustained rainfall. The remaining reservoirs continue to receive inflows and are steadily approaching higher storage levels. Bhatsa, Mumbai's largest source of drinking water, has reached 65.01% capacity, while Middle Vaitarna stands at 62.72% and Upper Vaitarna has reached 49.41%.

The BMC considers September 30 a crucial benchmark because reservoir levels at the end of the monsoon determine whether Mumbai will have adequate stored water to meet drinking water requirements until the next rainy season. If all seven reservoirs reach full capacity by the end of September, the city can generally depend on those reserves throughout the dry months. However, if storage remains below full capacity, conservation measures, including the existing water supply cut, may continue to prevent future shortages.

The decision underscores the civic body's focus on long-term water security despite the significant improvement in reservoir levels, highlighting that sustained storage capacity, rather than temporary monsoon gains, will determine whether Mumbai's water restrictions can finally be lifted.