State Highway 5, between Napier and Taupō. Photo: RNZ / Tom Kitchin
A business case to spend more than $600 million upgrading the highway between Napier and Taupō has won the initial go ahead.
Waka Kotahi is currently spending $13m improving the safety of State Highway 5.
But its board has also endorsed a much more expensive plan for the 140 kilometre stretch of road, which was hammered during Cyclone Gabrielle a year ago.
That plan, worth an indicative $630m, depends on winning funding during the next round of the national land transport fund 2024-27.
"This business case has been endorsed by the New Zealand Transport Agency board, and describes future investment needed to improve the safety, efficiency and amenity of the corridor," the agency said.
In the meantime, interim safety work including widening the highway and its shoulders, installing some barriers and rumble strips, linemarking and a wider centreline at a number of high-risk curves, would carry on until the middle of the year.