Downer has a rich history of building some of New Zealand’s most iconic and important bridges and tunnels.
We manage the full project lifecycle from design, value engineering, complex sequencing and programming, through to safe and efficient construction delivery.
We have deep experience across a comprehensive range of tunnels and bridge types, including major multi-span state highway bridges, single-span bridges, rail bridges, pedestrian and cycleway underpasses and overpasses, and Bailey bridges.
Our tunnel construction expertise includes the construction and maintenance of Intelligent Transport Systems (ITS), including critical fire safety and detection and safety systems, CCTV surveillance cameras, traffic signals, electronic signage and, smart lane controls and queue detection systems and IoT systems.
Projects are typically delivered in close collaboration with customers, subcontractors and stakeholders to harness value engineering opportunities and sustainable outcomes.
Downer has played a significant role in delivering many of New Zealand’s iconic and complex bridge and tunnel projects, such as the Homer Tunnel (to Milford Sound), the Rimutaka rail tunnel (linking Wellington and the Wairarapa), and Wellington’s Mt Victoria and Arras tunnels.
Downer is part of several alliances delivering complex bridge projects, including Mt Messenger Alliance (Taranaki), a six‑kilometre transport corridor construction with a tunnel and two bridges and Auckland’s City Rail Link, featuring the Te Horotiu Station bridges.
Other major bridge projects completed include the Homai Station Bridge, (a six‑span, 90‑metre structure built between two live rail lines using 15‑metre composite sections) and Hamilton’s Peacocke Gully Bridges, (spanning the Mangakotukutuku Gully as part of the 1.3‑kilometre Peacocke transport corridor upgrade).
The Homer Tunnel was built by Downer through the Ministry of Works in the 1930s and is still maintained by us today, under the Milford Road Alliance. The Milford Road, including the 1.2km Homer Tunnel, provides the only road to the Milford Sound, and as such, is a key transportation route for the tourism industry.
Completed in 2023, Downer replaced the 100-year-old single lane timber bridge at Kopaki on SH30, with a new two-lane bridge. The new bridge was built alongside the old one, allowing the road to remain open throughout the two years of construction.
The Ōpaoa Bridge project for the NZ Transport Agency, included construction of a new two-lane bridge over the Ōpaoa River on State Highway 1 (SH1), and the refurbishment of the historic Ōpaoa Bridge into a pedestrian and cycle way bridge, to improve road safety and access.
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