The Jan De Nul Group has contracted with Singapore-based PaxOcean Shipyard to convert three recently purchased offshore supply vessels into Water Injection Dredges (WIDs). The first one to be delivered was Giovanni Venturi, which will be mobilized for a project in Argentina. The other dredges, Henri Pitot and Henry Darcy, are in the process of being converted and will be delivered later this year.
The WIDs are fitted with power jetting systems used for the low-pressure injection of water into sediments, which causes them to fluidize and naturally move horizontally, just above the seabed, through natural sediment streams. Because the sediments do not need to be transported by means of a hopper, barge or pipeline, Jan De Nul said water injection dredging is also a cost-efficient dredging technique.
The dredges have Dynamic Positioning (DP), swell compensation for stable working conditions at sea, and diesel-electric drives to reduce the carbon dioxide emissions.
These vessels are smaller than traditional dredges and have high maneuverability and a limited draft, making them suited to maintenance dredging in smaller ports, and for other services, such as leveling the seabed for other installation services or for post-lowering of pipelines and cables in the seabed.