Transmission Gully and Northern Corridor
1The 27km, $1 billion Transmission Gully route forms the MacKay’s to Linden segment of the Wellington Northern Corridor. This part of Wellington lies over and around an active fault line, with the route passing through extremely rugged and difficult terrain. The project also needs to prioritise environmental protection, minimising the impact on the native plants and animals that live in the area. The video on the right shows a flyover of the Duck Creek to Cannons Creek section of the route.
We’ve been involved in the Transmission Gully and Northern Corridor project since 2007, bringing our creative bridging expertise to the varied challenges of such a huge project covering so much ground.
2 During the initial concept design stage, our contribution has included the preliminary designs of 29 bridges, which measure between 6m and 260m long – many of which span steep gorges with unstable sides. No two bridges in this project are the same, so our engineers have been hard at work coming up with inventive ways to create robust, resilient bridges that are still easy to construct in the difficult Transmission Gully terrain. We also helped to draft the documentation required for the Environmental Protection Authority, helping the scheme get the green light to proceed in 2012.
3 Right now, we’re working closely with architects, planners, landscape and visual specialists and NZTA to come up environmentally sympathetic bridge solutions that deliver the combination of performance, efficiency and value the project demands. We also took a key role in the Pekapeka to Otaki Expressway. During the initial scheme assessment phase, Holmes Consulting’s bridging engineers designed the 330m bridge that will cross the Otaki River. This huge, complex bridge will allow traffic to bypass Otaki to the east – a vital part in maintaining the flow of the route through times of heavy traffic.
For a detailed description and maps of the entire Wellington Northern Corridor, you can visit the NZ Transport Agency website.