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.

The present invention relates to a system and method for uncovering and removing pipeline from the seafloor using a subsea trenching system using pressurized water to uncover pipe, a subsea shear carried by a barge to cut lengths of the pipeline, and a grapple carried by a barge to lift cut lengths of pipeline for placement on a pipe haul and recovery barge.

A system and method for excavating an aggregate from below or beside a foundation through an access hole is provided. The system includes an air compressor and an air line fluidly coupled to the air compressor. The system further includes a valve disposed in fluid communication on the air line, and an end effector in fluid communication with the air compressor. The end effector extends between a first end coupled to one of the air line or the valve and a second end. The end effector is sized to fit through the access hole. The system further includes a nozzle coupled to the second end of the end effector.

System for removing sediments from a bed of a liquid environment such as a harbor or a pond, characterized in that it comprises a conduit (30), the lower extremity of which forms a moving suction mouth (31) that is to be placed substantially at the level of the bed, and the upper extremity of which leads into the open air so that said mouth (31) is under atmospheric pressure, said system comprising means for carrying out a local stirring operation (41, 42, 43, 44, 53) within said mouth and discharging means (50, 51, 52) connecting said mouth (31) to the surface of said liquid environment, in which these sediments circulate.

A hydro excavation heating system includes an internal combustion engine having an exhaust gas stream, a heat exchanger coupled to the exhaust gas stream and configured to heat hydro excavation water by transferring heat from the exhaust gas stream to the hydro excavation water circulating therethrough, and a tank for storing the hydro excavation water. The system also includes a water pump having an inlet coupled to an outlet of the tank storing the hydro excavation water, a hydro excavation hose coupled to an outlet of the water pump, and a coupling coupled to the hydro excavation hose and to an inlet of the heat exchanger to define a closed circulation path through the system when heating the hydro excavation water, where the coupling is configured to disconnect from the heat exchanger in order to use the hydro excavation water during a hydro excavation operation.

A fitting for an excavating apparatus can include a cylindrical pipe that can include a first metal material. In an example, the fitting can be configured for coupling to a hose. The pipe can include an interior surface and an exterior surface. Optionally, a perimeter of the pipe does not exceed a diameter of a first end of the pipe. The fitting can include a cladding layer (e.g., a second metal material) that can be coupled to the first metal material within the interior surface of the pipe. The cladding layer can include an abrasion-resistant material. The cladding layer can be coupled to the pipe such as with a welding operation. The cladding layer can include one or more ridges. The cladding layer can corrugate the interior surface of the fitting and exterior surfaces of the fitting which can come into contact with abrasive material.

A harvesting unit with one or more pumps including one or more suction nozzles directed towards the seabed, one or more inlets that lead from the suction nozzle to the pump, an outlet to a sorting device, one or more motors for driving the one or more pumps, where the sorting device, which at least separates shellfish from bycatch and foreign bodies, has an outlet for shellfish leading to a collecting unit, a structural main frame that carries at least the harvesting unit, and a towing and launching system for deployment and propulsion of the harvesting unit.

Hydro excavation apparatus for excavating earthen material are disclosed. The hydro excavation apparatus includes a first reservoir for holding a base fluid therein, a second reservoir for holding an additive therein, a vacuum system for removing earthen material from an excavation site, and an additive dosing assembly. The additive dosing assembly includes at least one of a pump and a valve fluidly connected to the second reservoir. The additive dosing assembly is selectively controllable to introduce an additive into at least one of the base fluid and the removed earthen material.

De-trenching apparatus (100) for extracting a buried line, such as a cable or pipeline, is disclosed. The de-trenching apparatus comprises a channel (112) configured to receive a buried line to be extracted, the channel comprising a first flared opening (114) at a front end of the de-trenching apparatus and a second flared opening (115) at the rear end of the de-trenching apparatus, the first and second flared openings each having a curved surface (111) configured to support the line during extraction, and material removal means for removing material from around the buried line ahead of the de-trenching apparatus.

Hydro excavation vacuum apparatus that process spoil material onboard the apparatus by separating water from the cut earthen material are disclosed.