As thousands in the state go thirsty, BMC data shows that the city wastes around 670 million litres of drinking water a day by using it for other purposes.
This is largely because most buildings that have not installed rainwater harvesting plants — which is normally utilised for such activities — do not have a separate tank to store non-potable water.
The Brihanmumbai Municipal Corporation (BMC) supplies 135 litres per capita per day of potable, treated water to every citizen in the city. However, each person uses 45 litres of this for other purposes, said civic officials.
Significantly, in addition to the 670 million litres that is used for non-drinking purposes, about 900 million litres is wasted every day because of pilferage and leakages. Effectively, nearly half of the drinking water supplied to the city is either misused or wasted.
Although the BMC made rainwater harvesting mandatory for buildings constructed after 2007 with a built-up area of more than 300sqm, this requires the installation of a separate storage tank for non-potable water. Hence, most of the old buildings in the city continue to use potable, treated water to wash clothes, cars and in toilet flush tanks.
“Projects such as rainwater harvesting must be incentivised by way of tax concessions. Most buildings that have the facility constructed have not maintained it, thereby rendering the system non-functional. The BMC is contradicting itself by not sustaining its own initiatives, which it started with much pomp,” said Rajkumar Sharma, Chembur-based civic activist.