Tansa started to overflow on Tuesday, becoming the fourth lake supplying water to the city to cross the full-supply mark.
The catchment area of the lake received 162.80mm rain between Monday and Tuesday morning, bringing the current water stock available with the civic body to 11,89,945 million litres — the highest in the past 10 years.
The water reserves are expected to last 300 days, said civic officials. While Vihar and Modak Sagar started to overflow on Monday, Tulsi cross the full-supply mark on July 19.
The officials said the seven lakes supplying water to the city are filled to 82% of the capacity, which is around 14.47 lakh million litres.
“Last year, we had announced a 20% water cut, but the situation is very good this year. The current stock will last for more than 300 days. We have one more month to go, which will add to the water stock. The rain between Monday and Tuesday has added 1,58,265 million litres of water to the city, which is equivalent to an addition of about 40 days,” said a civic official, on condition of
Tansa supplies around 400 million litres of water, of the 3750 million litres supplied daily. The remaining three lakes – Upper Vaitarna, Middle Vaitarna and Bhatsa -- are yet to reach its optimum level.
Upper Vaitarna and Bhatsa, which are owned by the state government, provide water to various other regions, along with Mumbai, while Middle Vaitarna is the only BMC-owned lake.
Bhatsa has reached 82% of its total storage capacity, while Middle Vaitarna has 81% water stock available. Upper Vaitarna is filled to only 60% of its total capacity.
The plan for distribution of water till July 31 is made on October 1 every year.