The sediment may be raised to the surface by one of several methods:

• a suction pump, normally trailed along the sea floor on a boom (converted ships may not have a boom)
• a system of buckets on a chain system that may be lowered tot he sea floor
• a system of grabs

The sediment nay be loosened by use of a cutter wheel situated on a boom at the bow of the ship. This cutter may be strong enough to cut through solid rock.

A dredger need not have any storage capacity of its own, but can transfer the spoil to another vessel, (e.g. a hopper barge) alongside.

Related types are:

• Hopper/Dredger - a dredger which can carry its own spoil in hopper-shaped holds designed with a system of bottom doors, for the subsequent dumping of the spoil in a different location.
• Dregder/Sand Carrier - a dredger designed with holds for the carriage of the spoil and an unloading system for the transfer of the spoil to shore.
• Hopper/Dredger/Sand Carrier - a dredger that may either dump the spoil, or transfer it to the shore (see above).