Waka Kotahi NZ Transport Agency is eyeing late 2020 to celebrate completion of the new State Highway 1 (SH1) Ōpaoa River Bridge, north of Blenheim, as final works get underway on this eagerly-awaited project.
The final works, including pavement and landscaping work, began in late September and are expected to continue until mid-October. During this time, there will be additional work to replace some of the bridge pavement, after inspections identified defects in the initial pavement layer.
Waka Kotahi Senior Manager for Project Delivery, Andy Thackwray, says the issues were identified through standard quality assurance processes.
“During construction, as road surfacing work is carried out, the pavement is subjected to robust testing so we can identify and remedy any issues before a project is completed.
“In this case, the top surfacing asphalt layer on the bridge was found to have deficiencies that, if left, would have resulted in replacement being required much sooner than its expected design life. The cost of remedial work will be at the contractor’s expense.
“I’m satisfied that steps are being taken to ensure the bridge is completed to the high standards that the public expects,” says Mr Thackwray.
Originally expected to be open in mid-2020, Waka Kotahi has kept project delays to a minimum despite the Covid-19 lockdown over the normally productive autumn period.
Earlier this year Waka Kotahi approved additional funding to construct a deeper pavement including a finished surface layer of Open-Graded Porous Asphalt (OGPA), which has an added benefit of being quieter and smoother on the approaches to the bridge. This deeper pavement material is not as susceptible to winter conditions, which allowed work to continue over winter months when pavement work would normally be paused.
“The application of OGPA will provide long-lasting benefits, as it offers a smoother, quieter and safer ride for motorists,” says Mr Thackwray.
The project includes work to convert the existing heritage bridge to a walking and cycling facility, joining the existing shared pathway between Blenheim and Spring Creek. Landscaping works will include a pou whenua, commissioned by iwi as part of the project, and an improved gateway to the town. An additional $0.6m was approved for improvements to the heritage bridge, including feature lighting and specialised cleaning.
While pavement works will be completed in mid-October, smaller projects to the side including landscaping, work on the heritage bridge, and reinstatement of the holiday camp below the new bridge will continue into November.
The total construction cost of the project is now around $22.7 million. The original cost estimate for this project was $21 million.
“With the project progressing so well we’re now starting to plan how we can properly celebrate the completion of this important regional project alongside our partners, stakeholders and community,” says Mr Thackwray. “This will be a truly spectacular asset for the community.”
A date to mark the project completion and unveil the pou whenua alongside the new bridge will be confirmed in coming weeks.
When complete, the project will offer a more reliable, resilient, safer route for freight transport and travellers on State Highway 1. While the old “banana” bridge is just 5.5 metres wide, the new one is ten metres wide, making it much safer for trucks and wider vehicles to safely pass each other.
More about the project: