A major slip overnight on State Highway 6 between the Gates of Haast Bridge and Haast Pass Summit means the section of road will be closed until at least Monday.
The road has been shut since Wednesday following storm damage and New Zealand Transport Agency West Coast area manager Mark Pinner said in some ways it was back to square one.
Mr Pinner said snow and overnight rain had brought down almost as much debris from a 50m high slip at Diana Falls, which had originally closed the road.
Three large boulders the size of houses which are perched above the slip site are a concern and the forecast "isn't that great for the remainder of the weekend".
Meanwhile, heavy snow which has not stopped has resulted in the NZTA being unable to open State Highway 94 from the Lower Hollyford turnoff to Milford Sound.
NZTA Southland area manager Peter Robinson said there had been half a metre of snow at road level and although the avalanche risk was moderate, it was still safe for contractors to work.
It was possible the road could open tomorrow or Monday but damage caused by the snow to the road would mean the road would then be closed from 5.30pm - 7.30am for repair work.
