A road sign reading: State Highway 2 open Photo: RNZ/ Kate Green
State Highway 2 between Napier and Wairoa is now open around the clock.
Cyclone Gabrielle wrecked the road, leaving Wairoa cut off from the rest of Hawke's Bay for three months.
It reopened during daylight hours a fortnight ago once a temporary bailey bridge was built at Waikare Gorge.
Waka Kotahi said it had now installed extra guard rails, reflective cat eyes and cones, making it safe to drive at night.
It also strengthened the Esk River Bridge on State Highway 2 - just north of the turn off to Taupō - so the temporary 30 km/h speed restriction has been lifted.
Maintenance and operations manager Jaclyn Hankin said there was still significant repair work ahead - but most of it was weather dependent, so would likely not be completed until spring or summer.
"In the meantime, work to maintain access and levels of service will continue throughout the winter months," she said.
There would still be temporary speed restrictions and stop/go controls in many places.
Opening the vital connection was a huge step forward in Waka Kotahi's cyclone recovery work, said Hankin.
"Being able to extend the opening to 24/7 is another boost for freight and the communities that rely on this key connection between Hawke's Bay and Tairāwhiti.
"We want to reiterate our gratitude to everyone travelling this road for their patience - it's been a trying time, and we're delighted to take another step toward a return to normality."