Motorists travelling to and from the West Coast glaciers are being urged to take extra care as the road reopens.
Contractors have been working since Thursday to clear a massive slip on State Highway 6 between Whataroa and Harihari.
New Zealand Transport Agency spokesperson Moira Whinham says there is still a lot of mud around.
"There's likely to be delays over the coming week. We will be reviewing them daily and looking to reduce them as quickly as we can."
The road is open at the top of each hour for 10 minutes between 7am and 7pm.
"We would encourage people to allow extra travel time in their journey… and also to take extra care."
One lane was opened with a traffic signal overnight.
The 400-metre landslide came down on Thursday after 180mm of rain fell, bringing with it 40,000 cubic metres of debris.
The South Westland A&P Show had to be cancelled.