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.

Cutting wheel system (1) for a dredging device, comprising a cutting wheel (2) and a cutting wheel drive system (8), whereby the cutting wheel comprises at least two cutting element rings (3), which rings are positioned at a distance from each other in parallel planes whereby the cutting element rings have coaxial rotation axes (12,13), whereby a suction tube (7) can be positioned between the two cutting element rings (3), whereby the cutting wheel drive system is arranged to rotate the cutting wheel about the coaxial rotation axes, wherein the cutting wheel system further comprises connecting arms (9) for mounting the cutting wheel in a rotatable manner to the dredging device, wherein the connecting arms are moveable with respect to each other between a closed position wherein the connecting arms engage the cutting wheel from opposite sides of the cutting wheel, and an open position wherein the cutting wheel is released from the connecting arms.

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 cutterhead for dredging a body of water. The cutterhead comprising a shroud including a top wall, a bottom wall, and two sidewalls each extending between the top and bottom walls. The cutterhead additionally comprises a rotatable cutterbar at least partially received within an interior space presented by the shroud, a first water-jet bar extending along a portion of the top wall of the shroud, and a second water-jet bar extending along at least a portion of one of the two sidewalls. The cutterbar and the water-jet bars are configured to generate a slurry of fluidized material from the water-bed.

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 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 boom assembly for an excavation vehicle includes a bracket configured to couple to a turret that is rotatably mounted to a debris body. Three or more telescoping support members. A first support member of the three or more telescoping support members is pivotably coupled to the bracket, a second support member of the three or more telescoping support members supports a shoe at a distal end, and a third support member of the three or more telescoping support members is disposed at least partially between the first support member and the second support member. The boom assembly also includes a single actuator. One end of the actuator is coupled to the first support member and the other end of the actuator is coupled to the second support member. The actuator is configured to extend and retract the second support member relative to the first support member.

A cutter head arranged to rotate about an axis of rotation for removing material from a water bed comprises a base ring positioned respect to the axis of rotation; a hub positioned with respect to the axis of rotation; a plurality of arms extending between the base ring and the hub, the arms comprising a plurality of cutting tools; and a plurality of skirts, each skirt extending from one of the plurality of arms to the hub to form a closed surface between the arm and the hub from a distal end of the cutter head toward the base ring and ending with a side configured to be parallel to a backplate, leaving an open channel between the skirt and the backplate.

A marine positioning system can have a floating platform, an external vessel, a positioning module, and a control module. The external vessel can be configured to selectively tow and maintain the floating platforming in a preselected position. The external vessel can have a propulsion unit. The propulsion unit can be configured to propel the floating platform in a preselected direction between 0 and 360 degrees. The control module can be in communication with the propulsion unit and the positioning module. The control module can be configured to receive the location data from the positioning module. Also, the control module can be configured to determine if the floating platform is in the preselecting position. In addition, the control module can be configured to generate instructions including the preselected direction that the floating platform needs to travel to be positioned in the preselected position.

A cutter head arranged to rotate about an axis of rotation for removing material from a water bed comprises a base ring positioned respect to the axis of rotation; a hub positioned with respect to the axis of rotation; a plurality of arms extending between the base ring and the hub, the arms comprising a plurality of cutting tools; and a plurality of skirts, each skirt extending from one of the plurality of arms to the hub to form a closed surface between the arm and the hub from a distal end of the cutter head toward the base ring and ending with a side configured to be parallel to a backplate, leaving an open channel between the skirt and the backplate.