Leaks can account for 10 percent or more of the water bill and waste both water and energy if the source is a hot water faucet. For example, a toilet with a silent leak of one cup of water a minute (a mere dribble) wastes about 2,700 gallons of water per month.
Although water may not be seen or heard running, the toilet may have a "silent leak". To test for a silent leak, mix a few drops of food coloring into the water in the toilet tank. DO NOT flush the toilet. Wait about ten minutes, and if the food coloring appears in the toilet bowl, the toilet has a silent leak.
The most common causes of toilet leaks are worn flappers, improperly adjusted water levels, worn valve seats, and leaking fill valves.
Watering lawns during the early morning or evening hours, since evaporation losses will be up to 60 percent higher during the day. Do not water on windy days. Set sprinklers so the lawn is watered, not sidewalks or driveways.