Work is set to begin next week on fixing a massive slip on State Highway One in Northland, which closed the road for a week last winter.
A go-slow detour has been in place around the slip since July, after a 70-metre stretch of the road near Maromaku slumped following days of torrential rain.
The Transport Agency said it had completed a geotechnical investigation and awarded the contract to Fulton Hogan.
The repair involves moving more than 3000 tonnes of material to build a stabilised-earth retaining wall with 39 reinforced concrete piles driven 21 metres deep.
The agency said the job would take about 18 weeks, and traffic would be down to one lane at weekends, in order to get the work done before winter.