With all the water faucets off, go to the water meter and look for a black and silver circle in the middle of the meter. Watch to see if it is moving. It may not move at first. You may have to watch it for FIVE MINUTES OR MORE. If it moves at all, you have a leak!
More often than not, a high water bill is due to a leaking toilet. Add food coloring to the tank. Wait 30 minutes or more. If dye appears in toilet bowl, your toilet is leaking. Check water level inside the toilet tank, if it is too high, it may be constantly running down the tube inside the tank.
A leaking toilet is hard to detect & can waste hundreds of dollars a month! One dripping faucet can waste thousands of gallons of water per year. Watch for wet places on ground from meter to house. Your underground line could be leaking! Keep a check on water at barns and water troughs.
Change your habits:
Do not leave water running while brushing your teeth or washing dishes. Take shorter showers! Use water-saving devices! When washing your car, rinse your car once, turn off water and wash from a bucket of soapy water. Rinse quickly again.