An apparatus for locating a buried utility conveyance, such as an undersea cable, beneath a body of water. The apparatus generally comprises a submersible housing that contains a variable ballast system for selectively controlling the buoyancy of the apparatus, operator-controlled maneuvering apparatus, and a detector assembly for locating the conveyance. The detector assembly includes first and second signal generators and first and second signal detectors for vectoring the location of the conveyance. An operator guides the detector relative to a target search location through cables attached to the housing and the variable ballast system. A camera generates images of the target search location for use by the operator to control the apparatus through an umbilical cable connected to the housing.