A stretch of road south of Whangarei on which 14 people have died in five years is to get safety posts down the middle.
The short-term safety measure will cover a 10km stretch of State Highway One between Toetoe Rd and Springfield Rd.
A half-metre wide centreline marked with a yellow no passing line on both sides and flexible safety posts with raised reflectors will stop vehicles crossing the centreline.
NZTA system design manager Brett Gliddon said it will prevent overtaking, reducing the chances of a head-on crash and making the road more forgiving of human error.
Gliddon said every crash, injury and death on our roads is a tragedy and NZTA is committed to reducing crash rates on this section of the highway.
He said the safety improvements are an urgent short-term measure and can be done quicker and cheaper than a wire rope barrier.
"These short-term improvements, which we hope will be implemented by June, are in addition to the ongoing and long-term programme of work to provide safer, easier and more reliable journeys between Whangarei and Te Hana."
NZTA said head-on crashes have accounted for 50 per cent of the 14 deaths and serious injuries on this stretch of road between 2012 and 2016.
Last month, three people died and one was seriously injured in a crash after a vehicle crossed the centreline.
Northland Regional Transport Committee chairman John Bain said he was delighted to hear plans to install the safety posts.
"Any safety barrier there that will reduce the number of crashes will be welcomed by all of Northland, I would hope."
The deaths in November showed how urgent the upgrade was, he said.
Statistics obtained by Bain show 17 people have died in 18 crashes between Toetoe Rd and the SH15A roundabout from 2006 to 2015.
In the same period, 24 crashes seriously injured 35 people and 51 minor injury crashes, injuring 141 people.
The numbers do not include fatalities since 2016.
Senior Sergeant Ian Row said the Northland road policing team supported and encouraged any steps by NZTA to make the high risk stretch of road safer.
"It's a very busy road and [drivers] need to take caution when driving along it because any small error could have tragic consequences.
"They can't afford to be distracted by cellphones or be speeding, because that's just going to end badly."
In August NZTA held a series of public meetings in Northland to consider upgrade options.
The options include upgrading the existing road to a four-lane expressway, upgrading the existing highway for southbound travel and building two lanes to the west for northbound traffic, or building a new four-lane expressway.
Construction on the four-lane upgrade between Whangarei and Port Marsden Highway, a 22km stretch of road, is planned to start in 2019.