Work is set to start on the first of two central Whangārei intersection upgrades which are happening alongside an upgrade to State Highway 1.
The Porowini Ave-Tarewa Rd intersection is first in line.
The upgrade will provide an additional lane on Porowini Ave at the western side of the intersection and an extra lane on Tarewa Rd at the northern side of the intersection.
Whangārei District Council roading manager Jeff Devine said the work will start on the Porowini Ave and Tarewa Rd intersection this month and should be completed in December.
"This will allow the traffic signals at the intersection to operate much more efficiently and will make traffic move much more smoothly during the evening peak."
The upgrade will cost $1.8 million and the contract has been awarded to local firm United Civil Construction.
In the next few weeks, contractors will demolish the former auto paint shop on the corner of Maunu Rd and Porowini Ave as the first step in widening that intersection.
The upgrade will include widening the bridge across the Raumanga stream to develop a separate left turn lane from Porowini Ave on to Maunu Rd and a new left turning lane from Maunu Rd on to Porowini Ave.
Work on that intersection will start in December and should be completed in May next year.
The cost has yet to be finalised but is expected to be similar to the $1.8 million for the first intersection.
Traffic management will be in place at both these sites, but the council is suggesting drivers take other routes and avoid these areas.
Around the same time work starts on the Porowini Ave and Tarewa Rd intersection, the NZ Transport Agency's $17 million upgrade of State Highway 1 and the intersection of Tarewa Rd will start.
Traffic lights will be installed at the intersection and the bridge on SH1 will be widened to four lanes. That work is expected to be completed in early 2020.
The council and NZTA are co-ordinating the projects, which are in close proximity, to reduce the impacts on commuters.
Motorists coming into the centre of the city from south of Whangārei may want to use Rewa Rewa Rd and Kioreroa Rd to avoid the roadworks.