A cutter suction dredger (CSD) is a hydraulic dredger that uses centrifugal pumps with a rotating cutter head to loosen, lift and transport dredged material.

Cutter suction dredgers may:

• have a pontoon hull without a means of propulsion (non-propelled), or
• be self-propelled, sea-going specially designed vessels.

Whether self-propelled or not, the cutter will be moored with spuds or anchors while at work so that in essence the dredging operation takes place with the cutter in a stationary position.

Small and medium size cutter suction dredgers can be dismountable and transportable over land. The hull is then composed of a series of pontoons, with the one pontoon containing the machinery.