Resealing work along State Highway 6, south of Nelson will take part in stages next week to prevent the road from closing, but motorists are being warned to expect their journey to take longer than usual.
Waka Kotahi NZ Transport Agency is resealing the Richmond Deviation and had planned to close the road and detour traffic onto residential streets.
Regional performance manager for the top of the south Mark Owen said the highway will now be resealed in one-third sections to allow two-way traffic, at 30 kilometres per hour while the work is being done.
"This will allow two-way traffic, at a slower speed past the work site, and we will need people to be patient while this work, then the loose chip sweeping and line marking afterwards, is completed."
The resurfacing work is expected to take a week, between the hours of 7am and 7pm with motorists asked to build extra time into their travel plans.
It was postponed several times due to rain earlier in the year.
Owen said the staged resealing would avoid congestion on residential streets near schools and neighborhoods, but the downside was the work would take longer to complete, so people would need to be patient.
Fine weather was forecast for Monday and the week ahead, so it was hoped good progress could be made.
The highway resealing needs to be completed in warm, dry conditions ahead of safety barriers being installed later this year. The barriers will keep opposing direction lanes of traffic safely separated and avoid head-on collisions which cause the most deaths and serious injuries.