State Highway 6 Dellows Bluff – containers removed early next month

State Highway 6 Dellows Bluff, south of Murchison, will be free of containers and back to two lanes by Wednesday 9 April, as contractors pause work to refine and improve plans to repair the slip.

SH6 Dellows Bluff, rockfall and slip sites.

Rob Service, System Manager Nelson/Tasman says contractors have been working at the second slip site, less than 200 metres from the original 2022 rockfall site, since February.   

“While it initially looked to be a straightforward fix, investigations show the site is far more complex and fragile than expected.”  

“The geology of the hill face presents a challenge for contractors. Initial plans were to tackle the slip from the side, but access has proven difficult, and the conditions have presented issues for our team.  

“The safest option is to pause work at this location while we revise plans to access the slip from above. We will return to the site as soon as possible to continue this important work,” Mr Service says.

While this means a slight delay in the project, Mr Service says significant progress has been made. 

“Rock-blasting work was done earlier this month to remove loose rocks and debris at the top of the slip. We have also removed overhanging trees, installed extra drainage and a catch basin for easier maintenance over winter, and resealed the road. It ensures the site is in good condition as we prepare for the next phase of work, once geological assessments are completed.”

Mr Service says all of the work carried out to date means the site is safe enough for the shipping containers to be removed. Their removal will make the road wider, allowing the highway to be restored to two lanes and the reduced temporary speed limit to be lifted.” 

The containers will be returned to the site when work on the slip resumes. 

Mr Service appreciates repairs at this part of State Highway 6 have been ongoing for some time. 

“We have had to deal with an underslip, rockfall, and another overslip – all in the same area. We know our work has affected the community and road users and we thank them for their patience and cooperation.” 

But with no local road detours available, this is a critical section on State Highway 6 and it is essential we do all we can to ensure it is safer and more resilient in the future. This work is vital,” Mr Service says.  

Contractors will monitor the slip site over the winter months and remedial measures will be implemented if needed. 

Works schedule for container removal

• Stop/stop controls with delays of up to 15 minutes will operate on Tuesday 1 and Wednesday 2 April from 7am – 6pm when the containers will be removed. 
• Stop/go controls will then be in place from Thursday 3 to Tuesday 8 April as contractors prepare the highway to be reopened to two lanes by Wednesday 9 April.
• Drivers can expect delays of up to 15 minutes under stop/go.
• Drivers must follow all speed signs and warnings in place.  

More information

• This work at the rockfall site has been funded by the Crown Resilience Programme - a $419 million investment package of resilience improvement activities that will reduce the impact of severe weather events on our national roading networks. The total crown resilience programme comprises $279 million for activities on State Highways, and $140 million for activities on Local Roads - Crown Resilience Programme (CRP)
• The work at the slip site is funded by a National Land Transport Programme emergency works allocation.
• Work has been ongoing at the area since a major rockfall in July 2022. This has seen rock scaling and rock blasting to remove overhanging rock and debris from the cliff face above the highway. Rock anchors, steel mesh have also been installed on the original slip. 
• A specialist sub-contractor from the region is being used on the project, based on their experience in forestry, earthworks, steep sites, and large earthworks machinery.
• The benching of the original slip site is permanent and allows contractors to maintain and monitor the face for further erosion or failures.
• Efforts will be made to retain and replant vegetation at the site. This will include replanting native plants on the bench and possibly the hill face. Contractors will eradicate wilding pines where possible.