Explosives to be used to blast rocks at Milford

Huge boulders that cover Milford Road after a giant landslide last week.
Huge boulders that cover Milford Road after a giant landslide last week.

The road to Milford Sound will re-open on Thursday, a day later than anticipated, the New Zealand Transport Agency says.

Thousands of people have been unable to get into Milford Sound after a massive landslide blocked the access road on Friday afternoon.

The section of the Milford Rd between Falls Creek and Monkey Creek was closed with large rocks and wet weather hampering work efforts.

NZTA area manager Peter Robinson said more than half of the slip had been cleared but the weather forecast for the next 24 hours included heavy likely to delay work.

Another factor in extending the re-opening to Thursday was to allow time to ensure the single lane through the slip was secure enough to be used by a wider variety of vehicles, he said.

"The slip had covered about 200m of road and included rock as large as 500 tonnes. Earlier reports of 200 tonnes were on the conservative side. The largest rock shown in images widely used in the media has now been successfully blasted and cleared away along with several smaller rocks."

Drilling rigs and two large excavators are being used to clear the slip.

Advice from geotechnical experts who inspected the main slip were being followed to ensure the safety of workers, he said.

It could be some time before the cost of this work was known, Mr Robinson said.

There will be a further update on the slip at midday tomorrow.

The Southland Times