"We will keep the existing traffic signals operating as long as possible while undertaking the preliminary works."
In early March, a temporary roundabout will be installed and the old signals removed.
While the temporary roundabout is in place, there will be pedestrian refuges in the centre of each of the intersection's approaches.
"The upgrade will significantly improve the intersection's safety for motorists and pedestrians," Holmes said.
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"As well as changes to the intersection layout, the traffic signals will include the latest software technology allowing the traffic signal cycle and phase times to adjust automatically to traffic volumes.
"During the intersection upgrade, we recommend that freight trucks to the nearby supermarkets approach from [SH3] London St, rather than Victoria Ave," Holmes said.
Work on the intersection is expected to be finished by the end of March.