Nelson is an isolated city surrounded by rugged topography and it depends on reliable roads. We should welcome the highway work that the New Zealand Transport Agency (NZTA) is starting in November on Rocks Road and the Whangamoa Saddle despite the disruption this will cause.
Rocks Road is a crucial arterial road carrying more than 20,000 people and 2,000 trucks a day, linking the city with the airport and the region with the port. The repeated closures during the June and July storms added to Nelson’s miserable winter and caused traffic chaos. I have been lobbying Ministers and NZTA officials seeking investment in improving its resilience.
The erosion and slips on Rocks Road are a major engineering challenge. The Tahunanui slump is NZ’s largest urban landslide and has been moving for thousands of years. It took eight years in the 1890s to excavate the cliffs and construct the stone walls to build it.
The southern section closest to Tahunanui is the most vulnerable. The work involves scaling the rock face, removing the loose vegetation, unstable material and old netting. This will be followed by installing new mesh netting and anchoring it to the cliff face. Shotcrete will also be used on other parts to prevent further erosion of the cliff face and matting in other areas to encourage natural vegetation. The work starts this Sunday and will continue until March.
This cliff face work poses risks to road users below and will require traffic management including temporary lane and road closures. The contractors will be doing their best to keep delays to a minimum. Council is also working with NZTA to ensure we are coordinating the timing of our road works so as not to compound congestion across the network.
The work on the Whangamoa Saddle involves replacing a culvert, resurfacing, clearing drainage, improving resilience and general maintenance. It will require night closures between 8pm and 5:30am, Sunday to Thursday, from 9 November until 28 November to be completed for the busy summer ahead.
These challenging sections of State Highway 6 will never be 100% reliable but these improvements will make our region more resilient to future storms.
