Hans J Marter

16 April, 2008

WORK ON dredging Lerwick’s north harbour to a depth of nine metres is set to start next week, creating up to 30 local jobs over the next eight months.

The £12 million project will be carried out by Westminster Dredging Company, one of the world's largest dredging contractors.

It will be the biggest project ever undertaken at the port, allowing large ships to enter the industrialised north of the harbour.

The job was delayed by almost three years after a bitter conflict between Shetland Islands Council and Lerwick Port Authority over a proposal to build a bridge to the nearby island of Bressay.

Legal action by the council in 2005 forced the port to pull out of a £7 million contract with Belgium dredging company Jan de Nul.

The dredging contract was re-advertised immediately after the Court of Session threw out the council’s interdict in January 2006, but the port is still awaiting payment of a £5.25 million compensation claim from the SIC.

The port has wanted to develop a deep water access since the beginning of the decade, alongside plans to reclaim land for industries such as oil rig decommissioning.

Almost 490,000 cubic metres of good quality material will be removed from the seabed during the eight month project, taking it from a depth of six to nine metres.

Most will be used to reclaim 5.8 hectares (14.4 acres) of land to the north of Greenhead Base, creating an additional area for decommissioning offshore oil and gas production facilities. The rest of the material will be stockpiled there for later use.

Port chief executive Sandra Laurenson said: "The deeper and wider access and the deepened berths will suit the larger vessels now operating and will be of particular benefit to the pelagic fish sector and offshore industry decommissioning, while the reclaimed land will offer opportunities to decommissioning and other industries."

Starting next week the large, self-contained, trailer suction dredger Waterway will spend around a month removing the softer seabed material by sucking it into an onboard hopper.

It will then move to the reclamation site where the material will either be pumped ashore through a temporary pre-laid pipeline, or blown ashore if conditions are right.

The back-hoe dredger Manu Pekka will then use its large excavator plant to dig out weathered rock, as well as fresh rock pre-blasted by a ‘drill and blast’ barge.

The back-hoe will load the material into two self-propelled hopper barges for delivery to the reclamation site where it will be dumped or, to assist placement, some may be trucked to the site. The Manu Pekka will operate from mid May to September.

In an overlapping phase, the ‘drill and blast’ barge will be operating from mid-June to August.

Meanwhile Westminster Dredging has established project offices at SBS's Greenhead Base. The company is bringing up a workforce of between 40 and 50 people, and in addition as many as 30 jobs could be created locally for the duration of the project.

Local civil engineering specialists Arch Henderson LLP is responsible for the design and supervision of what will be one of the largest marine civil engineering projects to be completed in Scotland this year.