Locating Buried Valve Boxes: Metal Detector and Witching Methods

Finding Hidden Irrigation Valves Under Sod

Need to locate valve boxes buried under established lawn.

Two Proven Methods

Method 1: Metal Detector + Probe

• Use metal detector to find valve box lids (metal rim) or solenoid bodies
• Follow with probing rod to confirm
• Most reliable for standard installations

Method 2: Wire Tracing / "Witching"

• Use two 24-inch brass welding rods with 4-inch handle bends
• Hold loosely, walk slowly — rods cross over water-filled pipes
• Trace mainline from known point (backflow preventer)
• Probe along traced path for valve boxes
• Requires practice but effective for non-metallic pipe

Modern Alternative

Professional wire tracers (tone generators) inject signal on control wires at controller, detected with receiver wand. Available at irrigation supply houses (Ewing, Horizon, John Deere Landscapes).