An apparatus for dredging using a pump which forms a highly pressurized, rotating stream of liquid which is directed down the inlet conduit to a discharge and the momentum and energy of the rotating stream is transferred to the solids and liquids, suspending the solids to agitate and separate the same to make the solids more easily suspended. The agitated solids and liquids flow upwardly in a counter-flowing outer annular stream around the downward flowing, rotating stream. The pump is very lightweight as compared to conventional centrifugal dredging pumps and is operated at high speeds, for examble 1,000-2,000 rpm to eliminate the usual speed reducers to prevent cavitation when using the centrifugal pumps.