18,5Km
highway
The project includes the design, construction, financing, operation and maintenance of the SH1 Highway Expansion in northern Auckland.
The contract also includes operation of the Metro. For this purpose, Acciona and Gülemark have partnered with Alstrom to head the operation.
There are 14,505 metres (m) of double track railway, with parking tracks of 230 metres and 1,109 metres with a third track.
The project consists of:
- A new line with 14.4 kilometres, of which 10.8 kilometres are developed with a double viaduct line, 0.9 kilometres of single viaduct line, 2.2 kilometres of tunnel and 1.2 kilometres of cut and cover.
- 7 stations, one of them an interchange, 4 elevated stations, 2 at tunnel level and an iconic station for EXPO 2020.
- 50 new trains, 5 cars each.
ACCIONA's Engineering Business Line provided specialised technical support to complete construction.
General Information
- Location: Auckland, New Zealand
- Type of contract: PPP (30 years)
- Infrastructure: Highway extension
- Construction end year: 2022
Key aspects
The public-private partnership (PPP) contract award to build the stretch of the Puhoi-Warkworth highway is ACCIONA's first project in New Zealand, which consists of the 18.5-kilometre four-lane North Highway extension from Johnstone Hills tunnels to North Warkworth.
This is the first stretch within the Ara Tūhono - Puhoi to Wellsford passage, which will contribute to the economic growth of the Northland region and provide a more reliable and secure transportation link with the triangle formed by the cities of Auckland, Waikato and Tauranga. Traffic from the Puhoi to Warkworth highway is scheduled to open in 2022.
Key figures
18,5
km of two-lane highway
100
km/h design speed
7
long viaducts
4
bridges
40
drainage collectors in two basins: Pūhoi and Mahurangi River.
8M
cubic metres of earthmoving for clearing
6.2M
cubic metres of earthmoving of embankments.
Technology and innovation
Geometric optimisation
Acciona was awarded the project in 2016 by the New Zealand Transport Agency after an 8-month competitive dialogue process where engineering value was considered one of the Client's main criteria.
Geometric optimisation guided the design throughout the process based on a cost-effective solution using a field-adjusted curvilinear alignment where the operating speed criteria allowed for the best design. A consequence of the terrain-adapted geometry is that the new alignment offered fewer structures and shorter viaducts. The final result was a reduced total length of structures from 2,350 m in the Conceptual Design to approx. 800 m long in the final design.