Jan De Nul has completed capital dredging works at Port Hedland in Western Australia. ‘The final portion of this three-year project was specifically challenging as it had to be executed within a fully operational and extremely busy port,’ says David Jonckheere, Area Director Oceania and Asia at Jan De Nul.

The port of Port Hedland is situated on the North-West coast of Australia and is Australia’s largest export port by annual throughput. It is also the largest bulk mineral export port in the world with iron ore being the main export commodity. Currently, there are approximately 6000 vessel movements each year.

Jan De Nul deployed hopper dredgers, a cutter suction dredger and split hopper barges to Port Hedland to dredge sections of the 42-kilometre long navigational channel. The project included the removal of high spots and the creation of two refuge zones and an emergency passing lane alongside the outer section of the shipping channel.

Barge Loading Mode

Strict environmental requirements and operational constraints within the busy port resulted in Jan De Nul adapting specific execution methods. As such, cutter suction dredger Niccoló Macchiavelli was mobilised in barge loading mode, assisted by two split hopper barges.

Normally, a cutter suction dredger sucks up material by means of its dredge pumps, which is then discharged through a floating pipeline and pipes on shore, to a deposit area. When discharging material into split hopper barges that are moored alongside, no pipelines are needed. Thereby the risk of temporarily jeopardising the safe use of the existing channel was reduced to a minimum and a non-compromised access to and from the berths in the inner port was secured.

Other Customised Innovations

Jan De Nul Group further customised its fleet in order to meet planning and strict operational and environmental requirements. The trailing suction hopper dredger Charles Darwin was fitted with an in-house designed ripper draghead, providing enhanced capabilities. This draghead was initially designed to rip through hard coral rock and is therefore capable of dredging very hard soil.

In addition and for specific areas within the dredge area, the hopper dredger Juan Sebastián de Elcano was equipped with an in-house developed milling draghead, adding to the flexibility and cost/time efficiency in executing the works.

Picture: Niccoló Macchiavelli in barge loading mode in Port Hedland.