It had been due to start on Tuesday, but minor changes were made to make things smoother for businesses in the area, Dunedin City Council city plan project director Dr Glen Hazelton said.
City buses had also been rerouted from Tuesday. "Having the bus detour in place a few days before work started meant we could address any issues and adapt the traffic management as required," Dr Hazelton said.
Sections of London, Filleul and Frederick Sts are to remain closed until April, unless the work is completed sooner.
"The full closure allows us to complete the work more quickly, which was the approach most businesses favoured," Dr Hazelton said.
Once surveying is complete, excavation will begin. Contractors will replace pipes and then replace kerb and channelling, and reinstate roads and footpaths. The overall central city upgrade, including a makeover of George St, is due to be completed in 2024.
