State Highway 6 has been closed to all traffic this morning with a massive rock falling onto the highway overnight about 15km west of the Gates of Haast.
The rock, measuring about 10m x 10m, came down about 1km west of Clarke's Bluff, says the NZ Transport Agency's Senior Asset Manager West Coast Mark Pinner.
"The rock is about the size of a house, weighing 200 to 300 tonnes. Early indications are that it will not be possible to remove the rock without blasting it into chunks.
"Our contractors are already on site assessing stability of the rock face and a specialist driller is heading to the site to begin work as quickly as possible to remove the rock and re-open the highway."
Mr Pinner says a specialist geotechnical expert is also on standby to fly into the area if required.
The road is currently closed to all traffic with the next update expected at 3pm. "The size of the rock does mean however that if we are able to get the road re-opened later today, it is likely to be only single-lane."
He says motorists are advised there are no alternative route. "Electronic sign updates are located on the highway at Lake Hawea and Fox Glacier and updates are also available at www.highwayinfo.govt.nz(external link) or by phoning 0800 4 HIGHWAYS 444 449."