Work on the Rangiriri section of State Highway 1 is set to continue until next week with contractors finding more repairs are needed.
The surfacing repairs began in September but the job has become bigger than first thought.
To help ease traffic flows, the southbound Te Kauwhata off-ramp had been re-opened. That would help Te Kauwhata, Rangiriri and Glen Murray motorists who had been detoured to Ōhinewai or were using local roads to access their communities since early last week.
Waka Kotahi NZ Transport Agency confirmed work in the southbound lanes would continue this week and was likely to stretch into next week as well.
The current southbound closure was the final large phase in remedial works. There were three separate, smaller repair sites outside the current work areas that would be completed with less traffic management and disruption, a Waka Kotahi spokesperson said.
