How does a bucket-ladder dredge remove material from the seabed?

A bucket-ladder dredge removes material from the seabed using a continuous, rotating chain of open-ended shovels or scoops mounted on a rigid, adjustable frame known as a ladder.12

The process functions as follows:
* Excavation: The ladder is lowered to the seabed at a slant. As the chain rotates, the empty buckets descend along the underside of the ladder and are pushed into the face of the material at the bottom.12
* Lifting: The buckets fill with material and return along the upper side of the ladder toward the surface.1
* Discharge: Once the buckets reach the top of the ladder, they turn over and empty their contents into chutes, which then divert the material into hopper barges for removal.12

This equipment is highly effective for land reclamation and harbor development because its positive digging action allows it to handle stiff soils and even soft rock, provided the buckets are equipped with hardened edges or ripping teeth. The dredge is typically held in position and moved across the working face using a system of moorings, allowing for precise control over the depth of the seabed.2