Workers were seen at the top of the pylons yesterday, preparing to lower the lines, as a part of Aurora Energy’s Otago Harbour Crossing project.
Project manager Ben Bulling said the first section of the overhead line, between Quarantine Island and Portobello, was successfully removed.
The second section, between Quarantine Island and Port Chalmers, would also be removed this week.
Special pressure gauges were needed to monitor the tension on the line as they were lowered to ensure the safety of the lattice tower, Mr Bulling said.
The lines were then fully lowered and winched on to a cable drum on the harbour side.
Where the lines needed to be lowered into the water, a buoy was connected to the end of the line and then monitored by a watercraft, he said.
Once the lines have all been removed, a helicopter and contractors will be used to dismantle the pylons.
The ageing towers have been replaced with two new submarine cables.
