A large hole in the road was discovered by Weston Volunteer Fire Brigade firefighters pumping water that had threatened homes in Grove St during heavy rain that soaked the district throughout much of November.
It was revealed a culvert had collapsed, which caused significant flooding in the area.
Westview Rd has been closed since late November while a plan was developed to fix the issue.
In a statement, Waitaki District Council roading manager Michael Voss the project had taken longer than expected to get under way, as two sections of the culvert had collapsed, one on land owned by the council and the other on land owned by KiwiRail. That meant a plan had to be approved by both parties.
Work would start this week, he said.
"We are looking at six weeks to completion depending on weather and subcontractor availability. I would suggest completion will be mid-March, though we will have more certainty on this shortly.''
Mr Voss said it was likely the road would be reopened to traffic by "the end of February or early March'', before repairs would be made to the present detour route.
Work to repair the Westview Dr culvert will involve the construction of a new chamber in the existing box culvert and a new culvert being laid on the outlet side of the road.
A new, secondary stormwater pipe will be installed through the rail embankment parallel to the existing box culvert and above the culvert, an existing sewer line will be re-aligned.
Backfill material will be replaced and compacted in layers before contractors reach the new road formation level before the road is re-constructed and sealed.
Waitaki Mayor Gary Kircher admitted the duration of the project was not ideal, but said it was important the appropriate work was carried out to avoid a similar incident happening again.
"Having the detour in place is definitely an inconvenience to need to get to the other side.
"It's been really important to get the work done right and that's complicated by the fact it's actually a couple of sections of culvert ... our team have been working on getting the best engineering solution.''
