State Highway 1 (SH1) traverses the Brenderwyn ranges, winding its way east-west across Northland to a mild height of 450 metres, where you see the mighty maunga Manaia before descending toward Whāngārei. These hills are a gateway to Northland, and the steep, winding highway through them is the primary link between the region and Auckland.
The New Zealand Transport Agency contracted United Civil to complete construction works on this $18.4m Safe Systems project, on the northern side of the Brynderwyn’s ranges – to make the 4.9km journey safer for road users.
Key features included:
- 700,000m³ of cut to fill earthworks in sensitive soils and steep topography providing a wider road with a safer alignment
- installing the 15kms of median and roadside wire rope barriers
- constructing bored pile and MSE retaining walls
- constructing 75000m² of pavement and associated surfacing works, using a multi-layer unbound granular design up to 580mm in depth with a lime modified M4 basecourse
- maintaining bi-directional traffic flow, without interruption, for the duration of the project
- extensive sediment and erosion control measures
- planting 100,000 locally-sourced trees as part of the wider landscaping work.
This project was completed within approved budgets and timelines. It also exceeded our client’s customer service expectations, regarding our quality service to road users throughout the works.
Today this stretch of the Brenderwyns is meeting the government’s Safe Journey’s vision of “a safe road system increasingly free of death and serious injury”.