Abstract: A pipe proximity warning device is operable for both cross-line and in-line digging operations to provide a warning to an operator that the bucket of a backhoe is in close proximity to a trace wire on a plastic pipe. The in-line system comprises two sensors located on the bottom of the bucket for detecting a signal on the trace wire. The distance to the wire is determined based upon a ratio of the signals detected by the two sensors. The cross-line system also has two sensors and also employs a ranging system that disables a geometry tracker when the bucket is outside an operable range of distances to the trace wire. From the angles of the boom, stick, and bucket, the geometry tracker determines the horizontal distance x and vertical distance z to the trace wire, both of which may be displayed to an operator in real-time.