A method of dredging which comprises suspending dredging apparatus 200 from a vehicle 360. The sediment agitating apparatus comprising a chassis 210, and mounted on the chassis are an extractor, sediment agitating apparatus and respective pumps 220, 230. The dredging apparatus 200 is disposed above, but not in contact with a waterbed 340 to be dredged of sediment 350. The sediment 350 is agitated then extracted with the extractor. The dredging apparatus 200 is moved around the water and the extracted sediment 400 is deposited underwater and above the dredging apparatus 200, so that the sediment 400 is transported and deposited away from an area being dredged by the natural movement of the water. Apparatus and use of the apparatus are also described.

Microdredging systems comprising a pumping platform and loading platform. In certain embodiments, system operates autonomously and is adapted to allow the loading platform undock from the pumping platform for disposal of the removed sediment.

Embodiments of the invention provide apparatus and method for seabed resources collection. The apparatus comprises a main module and a plurality of seabed resources collecting devices releasably attached to the main module, wherein the main module and the plurality of collecting devices are configured to be launched from a surface vessel towards a seabed; the main module includes a control module which is configured to determine a mining path for each of the collecting devices based on characteristics of the seabed, control each of the collecting devices to collect seabed resources along the determined mining path and control transfer of the seabed resources collected by the collecting devices, wherein each collecting device is configured to be released from the main module after the apparatus is launched, and to collect seabed resources along the mining path determined by the main module after being released.

A dredge head assembly is disclosed. The assembly includes: a shroud having a generally open bottom end and a top end; a screen structure covering the generally open bottom end of the shroud; a suction pipe with a first end connected to the top end of the shroud and a second end configured to be operatively connected with a pump which induces suction; a handle connected to and extending from the shroud and having at least one grasping portion; and one or more vacuum relief valve assemblies, each comprising a valve, at least one opening configured to be in communication with water, and an actuation mechanism positioned to be accessible to a diver. Dredging systems and methods of dredging are also disclosed.

A device for the removal of a layer of sludge and/or sand from the bottom of a wetland includes: a diving bell with an open bottom and a lower free edge; a unit for driving the diving bell with its lower edge into the layer of sludge to be removed; a dredge pump installed in the space of the diving bell and provided with an inlet for pumping up the sludge and/or an outlet to which a pipe is connected for pumping the pumped up sludge and/or sand to a collector; and a compressor for pumping gas under pressure into the space of the diving bell during dredging. The diving bell is also provided with a gas outlet for the compressed gas, the gas outlet being adjustable in height in the diving bell because the outlet is attached to a float that can float on the sludge.

An overflow system for a hopper dredger comprises an overflow tube; an inlet for taking in head water from the hopper; and a collector to collect the flow of head water entering the inlet and guide the flow to the overflow tube. The collector comprises a substantially horizontal top portion which delineates a top of a flowpath for head water into the collector to ensure substantially radial flow into the collector. At least one of the overflow tube and the inlet is adjustable for controlling flow into the overflow system.

A trash removal system for removing trash and debris from a water bottom is provided. The system includes a sled configured to ride along the water bottom, the sled including a jetting aeration system having nozzles which provide jets of pressurized air and water directed towards the water bottom; and a vacuum including a suction funnel adjacent the jetting aeration system which is configured to suck in trash and debris agitated by the jetting aeration system. The system further includes a conveyor configured at one end to receive the trash and debris sucked in by the suction funnel, and to transport the trash and debris to a surface above the water bottom.

An apparatus, system and method for removing and treating contaminated materials on a bottom of a body of water and introducing growth packets to revitalize the treated bottom of the body of water. The structure may comprise a vessel with an open face. The vessel may be lowered down to the bottom of the body of water with the face facing down. As a result, the vessel and the bottom form an isolated space. The structure may comprise at least one agitating device(s) for stirring up the materials inside the vessel so as to form a mixture containing the sediment materials which in turn contain the contaminants. Multiple at least one pipe(s) may be coupled to the vessel for transporting the mixture out of the vessel for processing (filtering, treating with chemicals, etc.) so as to neutralize or eliminate the contaminants in the mixture. Then, the treated mixture can be returned to the inside of the vessel via the at least one pipe(s).

A method of dredging which comprises suspending dredging apparatus 200 from a vehicle 360. The sediment agitating apparatus comprising a chassis 210, and mounted on the chassis are an extractor, sediment agitating apparatus and respective pumps 220, 230. The dredging apparatus 200 is disposed above, but not in contact with a waterbed 340 to be dredged of sediment 350. The sediment 350 is agitated then extracted with the extractor. The dredging apparatus 200 is moved around the water and the extracted sediment 400 is deposited underwater and above the dredging apparatus 200, so that the sediment 400 is transported and deposited away from an area being dredged by the natural movement of the water. Apparatus and use of the apparatus are also described.

A dredge head assembly is disclosed. The assembly includes: a shroud having a generally open bottom end and a top end; a screen structure covering the generally open bottom end of the shroud; a suction pipe with a first end connected to the top end of the shroud and a second end configured to be operatively connected with a pump which induces suction; a handle connected to and extending from the shroud and having at least one grasping portion; and one or more vacuum relief valve assemblies, each comprising a valve, at least one opening configured to be in communication with water, and an actuation mechanism positioned to be accessible to a diver. Dredging systems and methods of dredging are also disclosed.