Water meters measure the use of water at a particular location such as an office building or home. The force of the water coming into the building at the meter, turns the dial that keeps count of the usage. If you get a water bill that seems too high, more than likely it is not a faulty water meter, but a leak or a misread. To determine if the water meter is in fact wrong, you must eliminate the other causes of a high bill. If it is determined that these common problems are not the cause, then what is left is a bad meter.
Check your meter once a month and write down the numbers on the reading. Do this around the same time each month that the utility worker checks the meter. You will not get the exact same meter reading that the worker takes, but it will be close, and you'll be able to notice major discrepancies. The discrepancies are typically the result of a bad meter or a misread. Check the meter to see if the last read number from the bill is anywhere near the current meter reading. If it is, then the problem isn't a misread and is more likely a bad meter.
Look at the meter before leaving the house for the day and again when you get home. The meter numbers should not change if no one is in the house to use the water. If the meter has changed, you have a leak. In some cases, the leak gauge on the meter will spin when no water is running, but there is a leak somewhere. This shows a slow leak, so that you don't have to wait all day to see a change in the meter.
Examine your home and rule out indoor leaks. Look inside the home to see if there are any faucets or pipes dripping. According to Des Moines Water Works, checking your toilet for leaks is accomplished with a few drops of food colouring. Put the food colouring in the tank and wait 20 minutes. If the water in the bowl has changed colours, then the toilet is leaking.
Rule out outdoor leaks by inspecting the yard for wet spots and the outside house faucets for drips. If you find an area that is wet with no valid explanation such as rain, then you might have a leak. Have a professional check the area and repair the problem.