The depth of a water line from the meter to your home depends largely on the "frost line" in your area. If a water line is buried too shallow, it could freeze in winter, not only cutting off your water supply, but requiring an expensive repair. Always consult local building codes for the required depth.
In Placer County, Ca., where temperatures are typically more moderate, local codes call for the depth of a water line to be 12 inches deep, measured from the top of the pipe.
Mid-range climate considerations
In a climate similar to Howard County, Md., codes require the water line depth to be 36 inches deep, measured from the top of the pipe to the surface of the ground above.
Statewide depths can differ
Weather patterns in various states mean that recommended water line depths may be different depending on where you live. In Indiana, for example, Lake County in the northern part of the state near Chicago requires a 60-inch depth, while the water lines in southern counties located closer to Kentucky may be 36 inches deep.
Midwestern depth considerations
In northern Ohio, the required depth in the city of Clyde, located in between Toledo and Sandusky just south of Lake Erie, is 48 inches.