A head unit for a vacuum conduit includes a vacuum nozzle having a bore through which material can be suctioned. The head unit can additionally include a jetting system including jetting nozzle(s) configured to eject fluid jets at high velocity and a positioning system configurable to selectively position, orient, and move the head unit within a fluid medium utilizing fluid flow. In some embodiments, the positioning system includes a plurality of vector nozzles distributed about a periphery of the vacuum nozzle. In some embodiments, the vacuum nozzle has a sidewall in which a vacuum inlet port is formed, and the positioning system includes a moveable member that selectively blocks and unblocks the vacuum inlet port. A system can include the head unit and a controller that controls a vacuum pump in fluid communication with the vacuum nozzle and a jet pump in fluid communication with the jetting nozzle(s).