Abstract: A self-contained dredging module includes a unitary body adapted to be attached to the stick of conventional back hoe apparatus to convert it with minimum modification from dry land to sub-aqueous excavation. The body carries a dual cutter wheel, suction pump, and separate motors for driving the cutter wheel and the pump. The cutter wheel is arranged on the module in such a position that dredging is permitted when the stick is moved in one direction and also permitted when the stick and module are turned upside down and the stick is moved in the opposite direction.

Abstract: A cutter wheel for a cutter wheel type dredge has a pair of axially spaced wheel parts each carrying peripherally mounted scoops and a centrally mounted hopper. The scoops have open sides, bottoms and rear ends and the hopper has open sides with which the open sides of the scoops align. As the wheel rotates spoil is flushed laterally from the scoops into the hopper by the flow of water into the suction pipe at the bottom of the hopper. The rear of the scoops are elongated and have open ends to permit sticking soil to be flushed into the following scoop as the scoops are moved through water and scraper arms remove whatever spoil might remain in the scoops, thus ensuring the removal from the scoops of all spoil without the necessity of utilizing power to jet flush away sticking soil or stopping operations to remove spoil by hand.