Tauranga’s twin geographical challenges of slope and swamp have not impeded a rapid start to the district’s longest awaited roading project, the Takitimu North Link (TNL).
The 6.8km long project linking Takitimu Drive toll road through to Loop Road at Te Puna has long been an on-again, off-again affair for over 15 years as traffic volumes have ballooned on State Highway 2.
But Waka Kotahi regional manager for infrastructure deliver Jo Wilton says since commencing earlier this year, significant preparatory site work has been completed ahead of the busy summer earthmoving season.
“There has been a lot of initial groundwork undertaken to prepare and open up the site for commencing the project itself.”
This includes constructing haul roads and commencing a staging bridge on the Wairoa River site for construction vehicle crossings. Wairoa road has been re-aligned and sediment trapping ponds installed while extensive archaeological investigations have also been completed.
The coming season will see over 400,000 cubic metres of dirt being moved between cut and fill locations around the project, while over 3.0 million cumec will be moved through the project’s entire five-year lifespan.
“Other work underway includes the recent commencement of the Cambridge Road overbridge, due to be completed by late 2023,” she says.
With its multiple gullies and ridges, the project brings its own challenges, with timing between cutting through ridges and depositing fill on swamp and flat areas being critical.
The new Wairoa River bridge crossing and valley worksite is only one of eight bridges within the project, but by far the largest, at 347m long. Given the bridge’s swampy, flat approach on the Wairoa valley floor, extensive wick drainage has been installed to manage the water table. Meantime extensive bunding and pond construction to prevent silt and dirt run-off into the river has proven effective over the very wet winter period.
The Cambridge Road overbridge will be constructed using a top-down method, with the bridge built on current ground and excavated beneath it for the new road.
Wilton says a key focus for project operators has been securing supplies and equipment well in advance, ensuring continuity of construction at a period when materials can have long lead times for delivery, even from within New Zealand. She said at this stage the decision on whether the link would be a tolled road or not had not been made. Normally when a new state highway is built Waka Kotahi carried out an assessment to see if it meets the criteria to be tolled, as will be done with TNL.
A tolling assessment is expected to be completed this year, and if considered a feasible option, will be consulted on with public next year.
A key consideration is how a tolled road would fit in with the wider transport network, and with TNL that includes the fact Takitimu Drive already has a toll road, and whether tolling across both would be feasible or desirable.
The $655 million project is funded under the New Zealand Upgrade Programme, a $12 billion fund announced in early 2020 with road, rail, schools, and hospitals all part of plans to boost infrastructure by $10 billion over five years.
The 6.8km TNL project is however only part of a larger project that has been significantly curtailed.
Construction of stage 2 of the link, from Te Puna to Omokoroa was cancelled until at least the next decade by government a year ago, a victim of covid inflicted debt levels.
The 7km route will be protected for future work, but construction would require funding through the
National Land Transport Programme, and government officials said it was unlikely within the next 10 years.
Traffic volumes on the Omokoroa-Tauranga portion of state highway 2 have grown significantly in recent years with housing development in the district, with volumes of 20,000 vehicles a day equalling the Waikato Expressway’s numbers.
In its current state it has been rated as one of the country’s highest risk rural roads.
Wilton confirmed traffic volumes were expected to grow to over 30,000 a day along the state highway route over the next decade.
Takitimu Northern Link project
- 6.8km long four lane corridor
- Separated walking and cycling path
- $655 million
- Opening late 2026
- New Wairoa River bridge crossing
- Overbridge interchange at Minden Rd
- Underpasses at Cambridge and Wairoa Roads
- New westbound lane connection from 15th Ave to Takitimu toll road