One of the biggest projects that Van Oord is working on in Dubai is ‘The World,’ which will consist of some 300 islands that taken together will form the shape of the world continents. A 25km long breakwater is also being constructed to guarantee the safety of future residents.

Constructing this 6km x 9km project involves dredging and placing 300 million m3 of sand and 30 million tons of rock. Van Oord started in 2003 with land reclamation and completion will take place in 2006.

The trailing suction hopper dredgers, which supply sand for the projects in Dubai, the cutter suction dredgers that are used to shape the forms of the islands, crane barges and mobile cranes, are all equipped with DGPS or RTK-DGPS. ‘With each project we have selected receivers based on the type of work and the accuracy needed. For example, almost every hopper dredger in our Dubai fleet has a DSM 132 on board,’ said Balvert. This high-performance sub-metre GPS receiver that also houses an MSK beacon and satellite differential correction receiver uses free public (MSK beacon or WAAS) or subscription-based private differential correction services to calculate sub-meter positions in real time.

‘Our cranes have extra sensors that are interfaced with the Trimble MS860 GPS receiver to a computer that runs software we specially developed, Balvert continued. ‘Machine operators can monitor their activities in real time on a screen within their operator compartments.

This way they can precisely follow the design plan. We use a similar system for our dredgers, while dredging sand from the bottom of the sea. Both depth and the quantity of sand taken are recorded and monitored in real time on the screen. Clearly, it's critical that each island is formed as designed and constructed on the exact position shown on the plan. By using the Trimble MS860 the precise position of the crane and the future island are provided right at the site.’ The Trimble MS860 receiver is a 36-channel L1/L2 RTK GPS model with dual antenna input which uses an advanced RTK technique to output both position and heading for precise positioning. Positions are delivered up to 20 times per second with a latency of less than 20 milliseconds. This responsiveness is matched with horizontal accuracies of 20mm and vertical accuracies of 30mm.

To survey the new Dubai islands, Trimble TSC-2 hand-held controllers are being used. The Trimble controller is a rugged and adaptable data collector that uses a Microsoft Windows operating system. The full keyboard, touch screen, colour graphic display and large memory capacity enable field operators to choose the most efficient data control for their various needs. Van Oord operates the Trimble controllers in combination with the Trimble R7 and R8 GPS receivers with R-track technology as well as the Trimble 5700 and 5800 GPS receivers.