Manawatū Gorge to remain closed pending geotechnical assessment of slip sites


The NZ Transport Agency is advising that the Manawatū Gorge will remain closed for at least three more weeks while safety works and geotechnical assessments are completed.

Manawatu Gorge slip

Anzac slip wall repairs 14 June 2017. Photo credit NZ Transport Agency

Transport Agency Highway Manager Ross I’Anson says while physical repair work, including the installation of new rock fall netting and the reinstatement of a damaged retaining wall, are on track to be completed by the end of this week as planned, further geological assessments of the slip sites are needed to assess the level of potential risk of further slips or rock falls before the road can be safely opened.

“We’re working with our contractors and independent geotechnical engineers to complete these assessments as soon as possible, but these evaluations must be thorough to ensure that the road is safe when it is re-opened.

“While the slips have been cleared and the road has been repaired at both sites, the slips have altered the rock faces above the road, and we need to thoroughly assess any additional risks that the newly exposed rock might pose for road users. The recent slips have resulted in new cracking in the rock faces on either side of the slips and we need to identify if there is a risk of additional rock falling onto the road, and most importantly what additional work may be required to provide further protection for road users. The geology of the gorge is complex, and these assessments must be very thorough to address that complexity.”

Mr I’Anson says it will not be known what, if any, additional work may be required until the geological assessments are completed, a process that is expected to take up to three weeks. Further information will be provided as it becomes available.

“We understand how frustrating the current situation in the gorge is, and we know the significant impact it is having for road users, businesses and residents, but the safety of road users is paramount.”

Mr I’Anson says in parallel with the geological assessments of the gorge slip sites, the Transport Agency will be progressing with the Detailed Business Case process to look at all of the options available to provide a long term, resilient and safe connection through the Ruahine/Tararua Ranges. 

“This is a very significant route that forms a strong link into the central freight hub of the Manawatū and provides vital connections for people in the region. The Transport Agency is focussed on providing strong resilient transport links that contribute to the region’s economic growth and prosperity.

With the Pahīatua Track and the Saddle Road continuing as the alternative routes while repairs to the gorge road are carried out, motorists are also being reminded to be patient, drive to the conditions and watch their speeds when driving through the communities along the alternate route.