Precise Maintenance Dredging
The Sanctuary Cove marina, on the Coomera River in the Gold Coast region of Australia, has grown significantly in recent years to now include four man-made marinas with over 300 moorings, as well as a dedicated superyacht berth for vessels over 24 m long. The marina enables direct access to the Pacific Ocean via the protected waterways of the Gold Coast Broadwater (without height restrictions) and the Coomera River.
As part of its marina maintenance activities, McQuade Marine was contracted to dredge in and around the tight confines of berthing pockets and pontoons within Sanctuary Cove–and all within a two-week time frame to minimize disturbance to boat owners and nearby residents. The total material quantity that needed to be removed was approximately 5,550 cubic meters of mud-like material that included silt, sand and clay.
McQuade combined advanced GNSS-enabled machine control software with purpose-built marine software to support underwater surveys and dredge-head actions to facilitate the Sanctuary Cove maintenance dredging project.
The McQuade team utilized one of its 45-ton Komatsu PC450 long-reach excavators on a purpose-built barge for dredging. Material was moved to the contractor’s split-hull trailing suction hopper dredger, Faucon, for transport to other parts of the marina.
The team used the Trimble Earthworks machine control system on an excavator with a Trimble Marine Construction (TMC) software overlay to provide a real-time view of the Faucon, the barge GHT1 and the excavator, along with the surveyed surface, design and dredged depth. TMC enables 3D visibility of the seabed profile to precisely target and remove only the needed material. Hydrographic surveys were regularly uploaded straight into TMC, enabling the excavator operator to maximize targetable material and focus on areas not within tolerance.
Operators on the dredger and the excavator were also connected via Wi-Fi, with TMC software allowing both the operator and skipper (master) to share the vessel’s positioning and 3D model information in real time. Wi-Fi was utilized for verbal communication and coordination between master and operator to optimize positioning and maneuvering. The operator was also able to generate volume progress reports at the click of a few buttons for the project management team and the customer.