SH3 to remain closed through Manawatu Gorge


The NZ Transport Agency has confirmed that State Highway 3 through the Manawatu Gorge will remain closed to traffic for at least two weeks following a geotechnical assessment carried out on-site earlier today.

The assessment by a specialist geotechnical engineer has revealed tension cracks in the rock face above the road at the site of yesterday afternoon’s slip near Ashhurst.

Transport Agency Regional Performance Manager Mark Owen says that while the amount of debris which came down in the slip yesterday is not large, the unstable state of the rock face above the slip site means the road cannot be re-opened to motorists for safety reasons.

“The engineer’s advice is that these cracks have rendered this rock face unstable, and the site is prone to further rock falls, which makes it unsafe for motorists until the unstable rock can be removed.

”We know that this is a critical route for the region, but the safety of motorists is our number one priority and we need to be sure that the site is stable before we re-open SH3.

“We understand that closures like this are frustrating and have a significant impact on people and on businesses. That’s why we’ve put a lot of work into making both SH3 and the alternate routes on the local road network more resilient over recent years.

“Those alternate routes will remain open while we work to stabilise the rockface at the slip site and get SH3 open for traffic as soon as possible,” said Mr Owen.

Mr Owen said that specialised equipment will be required to remove the unstable rock at the site of the slip – this is likely to involve the use of compressed air machines. This equipment will be sourced over the weekend and work will begin on Monday.

Regular (daily) updates will be provided to media and the public to keep people informed on progress.

Mr Owen also asked drivers to take extra care while using alternate routes with heavy rain forecast in the region at times over the weekend.