In big cities like Bangalore, a huge population lives in large apartment complexes. The biggest problem with these buildings is how we track and pay for water. Most apartments do not have separate water meters for each individual flat. Instead, the whole building gets one massive water bill, and the society divides it equally among all the families., Why it happens:, Because of this "shared bill" system, there is zero financial reason for anyone to save water. If my family takes quick showers and immediately fixes a leaking tap, our water bill stays exactly the same. If my neighbor washes their balcony with a hose and leaves the tap running for an hour, their bill also stays the same. The people who save water end up paying for the people who waste it., Scale and Impact:, This creates a huge behavioral problem. Nobody feels personally responsible for the water they use. In cities that constantly face extreme water shortages and have to rely on expensive private water tankers during the summer, this outdated billing system causes millions of liters of water to be completely wasted every single month., Conclusion:, We will never solve the urban water crisis by just telling people to "save water." As long as water isnt measured and billed per individual household, the waste will continue. We need a way to track consumption at the micro-level so people are held accountable for what they actually use.