How to Locate Underground Cables
Locating underground cables can be challenging and can take a lot of time. Underground cable locators, time-domain reflectometers and underground cable markers are a variety of specialized tools you can rent to accurately locate the cables. Fortunately, there are venerable techniques to find underground cable that use common household items such as wires hangers, copper or metal detectors.
Caution: In most states, you are required by law to "call before you dig." Call "811", or go to the Call811 website. A utility service person will come to your home within a couple days, locate the cable, power and phone lines. This is a free service.
Driveway lights are often found 3 inches to 6 inches from most driveways. You can also locate automatic lawn watering sprinklers or cable lines extending from your home to your garage with a few options that won’t leave your yard full of holes.
An easy and inexpensive way to locate cables is to use two steel wire hangers or approximately 8-inch copper wires known as a Divining Rod.
- Cut then bend the wires into an “L” shape with about 3 inches on one stand and about 7 inches on the other stand.
- Bend the 7-inch part of the “L” a little bit larger than a 90-degree angle.
- Grasp the two 3-inch sides with one in each hand. Droop both wires slightly in front of you.
- Stroll leisurely and methodically across your yard. As you get close to a buried cable or pipe, the hangers begin to swivel in your hands. The wire hangers slightly move in parallel with the buried cable.
- Do this from both directions across the yard and mark each time you locate parallel movement.
- This method works better on current-carrying wire cables, but it can help locate water pipes and cable television cable. Copper wires work the best.
- Another method to locate underground cables is to use a metal detector. The inexperienced user should be patient enough to listen for the difference between buried cable and metal bottle caps, beverage cans, and small amounts of metal that may be underground.
- Remember to always mark the locations and take measurements as you go. It is helpful to make a map of the locations for future reference.