Dredger (TSHD, CSD, BHD, BD)

Dredgers remove material from the seabed and split by the method of excavation. A trailing suction hopper dredger drags a draghead along the bottom and pumps the spoil into its own hopper while underway, suited to maintenance dredging of channels. A cutter suction dredger uses a rotating cutter head to break compact material and pumps it ashore through a pipeline, suited to capital dredging in stiff soil and rock. Backhoe and bucket dredgers excavate mechanically for precise or confined work.