Work paused after site found to be ‘complex and fragile’

Work to remediate a second slip site at Dellows Bluff south of Murchison has stopped after the site was found to be “more complex and fragile” than expected.

Containers will be removed from the State Highway 6 site, with both lanes reinstated by Wednesday, 9 April, as contractors pause work to refine and improve plans to repair the slip, according to NZTA.

System manager Nelson/Tasman, Rob Service, says contractors have been working at the second slip site, less than two hundred metres from the original 2022 rockfall site, since February, but acknowledges work in the area has being ongoing since 2022.  

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

“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.”

Rob says significant progress has been made, but the pause will delay the work.

“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.”

He says the site is safe enough for the shipping containers to be removed and the temporary speed limit will be lifted. However, the containers will be returned to the site when work on the slip resumes.

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