The work also involves upgrading the services at the intersection, including the undergrounding of powerlines, installing a new water main and preparing and sealing the road surface for its new function.
Wilton said upgrading the intersection, while continuing to have the same levels of traffic travelling through it, was a difficult task which had required careful planning and consideration.
"We have been working closely with our contractor to ensure we minimise the impact of construction works on the community."
On Thursday, October 8, the existing Tarawera Rd roundabout will be replaced overnight with a temporary, larger roundabout, which will be installed using hit sticks.
This new layout will be in place until January 2021 and will allow contractors to work on the service upgrades in larger sections of the intersection without affecting the live traffic lanes.
"We have made sure the temporary roundabout includes the same lane formation as the old roundabout, so the way people use the intersection will not change," Wilton said.
A temporary speed limit of 30km/h will be in place at all times during construction to ensure the safety of the public and contractors. The new speed limit will make travel through the intersection slower and cause some delays at peak times.
"We are asking motorists to expect, and plan for, more significant delays while people are getting used to the new layout."
After January 2021, the temporary roundabout will be adjusted approximately once each month until April 2021 so contractors can access all remaining areas of the intersection.
The work from September to April will predominantly be to upgrade services and construct the new road surface, as well as preparing the site for its final formation as a signalised intersection.
Once the service upgrade is complete, the temporary roundabout, and all other traffic management, wiIl be removed and the traffic lights will be switched on.
The signalised intersection is scheduled to be complete by the end of May 2021.
