22 July,2026 12:35 PM IST | Mumbai | mid-day online correspondent
Tansa is one of Mumbai`s key water sources and has a maximum storage capacity of 14,508 crore litres. Pic/ X
Continuous monsoon rainfall has led to Tansa Lake, one of the seven reservoirs supplying drinking water to Greater Mumbai, overflowing at around 8:51 am on Wednesday.
Following the overflow, authorities opened the gates of the Tansa Dam to regulate the rising water level.
Tansa is one of Mumbai's key water sources and has a maximum storage capacity of 14,508 crore litres. The lake's overflow comes amid sustained rainfall across the catchment areas, further strengthening the city's water reserves during the ongoing monsoon season.
The development marks another milestone in Mumbai's monsoon water storage, with multiple reservoirs nearing or reaching full capacity after continuous rainfall over the past few weeks.
Heavy rainfall over the city's lake catchment areas has significantly boosted the drinking water reserves, with the total stock in the seven reservoirs supplying water to the metropolis rising to 8,95,907 million litres (ML), or 61.90 per cent of the total useful live storage capacity, according to the Hydraulic Engineer's Department at the Bhandup Complex.
Between 6 am on Tuesday, July 21, and 6 am on Wednesday, July 22, the city's water stock increased by 4.15 percentage points, rising from 57.75 per cent to 61.90 per cent, following widespread rainfall across the catchment areas.
[mumbaiwaterstock]
Bhatsa, Mumbai's largest water-supplying reservoir, currently holds 4,10,644 ML of water, accounting for 57.27 per cent of its useful live storage. The lake also registered the highest rise in water level over the past 24 hours, increasing by 1.72 metres.
Heavy rainfall continued across the reservoir catchments, with Upper Vaitarna recording the highest rainfall at 224 mm during the last 24 hours.
Rainfall recorded at other lakes was:
Bhatsa: 96 mm
Middle Vaitarna: 71 mm
Tulsi: 71 mm
Tansa: 70 mm
Modak Sagar: 67 mm
Vihar: 65 mm
The combined storage of Upper Vaitarna, Modak Sagar, Tansa and Middle Vaitarna has now reached 4,49,519 ML, or 64.72 per cent of their total live storage capacity.
The Bhandup Complex recorded 52 mm rainfall in the last 24 hours, taking the season's cumulative rainfall to 2,006 mm.
The Hydraulic Engineer's Department said the Middle Vaitarna WSCPO gate has remained closed since 2 pm on July 6, while Upper Vaitarna water release has remained suspended since 10 am on July 6.
Vihar Lake has been overflowing since 9 pm on July 7, while Tulsi Lake has been overflowing since 11:43 pm on July 7, reflecting the sustained monsoon inflow into Mumbai's water supply system.
