Basslink Repair Relies on Calm Sea and Good Weather

Basslink operator has informed that repair work on the cable continues to progress well, and that the interconnector remains on track to return to service in June as previously advised.

Basslink’s cable repair vessel recently underwent planned modification works in Geelong which is necessary for it to carry out the next phase of the repair operations, before returning to Bass Strait on Tuesday.

“While in Geelong, the team unloaded more than 84 tonnes of damaged cable, prepared the vessel to receive the 90 tonne cable reel, loaded additional cable and specialist equipment, and changed over some crew members,” said Basslink CEO Malcolm Eccles.

“The team is currently utilising remotely operated underwater vehicles to conduct a survey of the seabed where it is proposed to lay the cable bight.

“We will then commence work on the first of three joints that need to be completed as part of the repair. Each joint will require six days of clear weather to complete.”

Requires calm sea and good weather conditions

As the jointing works take place on the deck of the vessel and are highly susceptible to weather conditions, each joint will require a window of relatively calm sea conditions and clear weather for six continuous days to allow such works to be completed safely. Bad weather or rough sea state can damage the cable, result in abortive jointing works or pose unnecessary occupational, health and safety risks for the repair crew. The jointing works will see the three lengths of new cables joined to the existing cables and bundled together, before being laid on the seabed.

Once all three joints have been completed, Basslink will lay the cable back in the existing trench where possible, and natural seabed movement will bury the cable over the coming months. Where this is not possible, Basslink will use a jetting process to excavate the seabed under the cable, after which it will sink into the sediment.

After the first joint has been completed, the vessel will return to Geelong where it will load the remaining spare cable required to complete the repair. The vessel is then not anticipated to return to port until all jointing works are finished.