The twin overflows mark a significant milestone in the monsoon season, arriving earlier than in previous years. Vihar Lake, completed in 1859, has a live storage capacity of 27,698 million litres and supplies an average of 90 million litres of water to the city daily. Tulsi Lake, constructed in 1879, has a live storage capacity of 8,046 million litres and contributes around 18 million litres per day. Both are among the only two lakes located within BMC limits, with water overflowing from Tulsi feeding into Vihar, and excess from Vihar eventually joining the Mithi River.
