Ahaura Bridge

Community relationships at the heart of successful delivery.

Ahaura’s previous single-lane bridge was simply no longer enough to support growing State Highway 7 traffic, especially in peak tourist season.

Our role was to replace the old bridge with a new 220-metre two-lane bridge, including building and re-aligning 1 kilometre of roading to support the new infrastructure. Work also included a pedestrian path on the upstream side of the new bridge, linking the south to Ahaura township.

The remote location of this project made for a challenging environment, with a lot of stakeholder involvement and environmental compliance to consider

Our work
Construction of 12No. 1.8m diameter concrete piles bored to depths of up to 25 metres and reinforced with 40 MPa concrete.

Fabrication of seven 30-metre concrete super-tee beams offsite, transported to Ahaura via Arthurs Pass – requiring detailed logistics planning.

Pouring of the bridge’s concrete deck in-situ.

In-house design and construction of all temporary works and staging platforms to support our 280-tonne crane and 67-tonne drill rig, to allow for the possibility of high river flood levels.

Demolition of the old bridge after the commissioning of the new one.

Our Environment
This was a high-risk project from an archaeological point of view. There were two sets of 19th century remains on-site, as well as some unique artefacts, which HEB crews were careful to work around in collaboration with Heritage NZ partner WSP. Additionally, key to the success of this project was the protection of local fish and bird species, the careful control of sediment discharge, and the provision of two cleanfill dump sites within the construction site, so cleanfill waste did not have to be removed via the public highway and so potentially impact local communities. Close consultation with local stakeholders and community members helped ensure we performed all work to the expectations of the locals.