"Safety is our top priority at Waka Kotahi. There is a history of serious crashes through this area, including the recent crash at Kuku where four people lost their lives.
"We have been investigating what safety improvements we can bring forward to make the road safer sooner. As a result, we have identified safety improvements for SH1 through Kuku that we can put in place before Christmas, with the remaining work to be completed next year."
The improvements through Kuku include resurfacing the road, repainting line markings, and new signage.
The new line markings will permanently remove the passing lanes between Ohau Rail Overbridge and Tatum Park conference centre.
The new road layout will include wide painted centrelines, which provide more separation between vehicles, and wider road shoulders.
Flexible marker posts known as safe hit posts will be added to the centreline in some areas.
The changes will be completed before Christmas when holiday traffic ramps up, Stewart said.
Kāpiti mayor K Gurunathan re-issued a plea demanding urgent safety action to fix the "killing fields" stretch of State Highway 1 after the fatal crash.
The deaths highlighted the urgent need for the Government to build the new expressway earlier, he said.
"Following two consecutive accidents and deaths back in November 2018, in a joint statement with the Horowhenua Mayor, I reminded NZTA of the observation made by former coroner Philip Comber who noted that over the past 25 years the road had become "a killing field marked like a battlefield with white crosses".
"It's now November 2021 and little seems to have changed," Gurunathan said.
The 2018 deaths occurred in the space of a few hours.
Wendy Kauwhata, 54, died at the scene of a two-car crash. Then, about 7km south of that crash, another person died in a separate incident on the same day involving a car and a truck north of the intersection of Waikawa Beach Rd and State Highway 1.
Stewart said work has been progressing on the new four-lane highway from Ōtaki to north of Levin that will improve safety for people travelling on State Highway
But construction isn't scheduled to start until 2025.
"We are investing in improvements to SH1 while we plan the new Ōtaki to north of Levin highway. Safety improvements and safer speed limits will help keep everyone on this road safer while we work to deliver the new highway within the next decade."
