I take an acre to be about 4000 sq.metres. 1 mm of rainfall on this equals 4000 litres of water...4KL. If I take Anantapur in AP as an example, with its annual rainfall of 400 to 700mm of rain, I get an average of 1 to 2 mm of rainfall per day.
Taking 1.5mm as the average, my water usage per...