Open your meter pit using pliers to unlock the lid and read the meter. The dial has a row of numbers which turn when water is being measured through the meter for delivery to your home. Make a written note of these numbers.
Also on the face of the meter is a red hand that reads similar to a clock from 1 to 10. These numbers measure by the gallon; the divisions between each number represent tenths of a gallon. Make a note of the location of the dial at this time.
After waiting one hour without using any water in your home, return to the meter pit and read your meter again. If the red hand has moved, water is being measured as it passes to your home. To determine the amount of water lost, subtract the first reading from the second reading; the result is the amount of water lost in one hour. For billing purposes your meter is read in thousands of gallons (the white digits in the diagram).