The cost of the Waipapa roundabout has almost tripled to $25 million because the project went from being a simple intersection fix to a whole-town infrastructure upgrade, roading authorities say.
The long-awaited roundabout, at the junction of State Highway 10 and Waipapa Rd, was the first roading project in the country paid for by the Provincial Growth Fund.
Since former minister Shane Jones announced the $9m cash injection in early 2018 the price tag has shot up to $24.5m, with the extra $15.5m to come from the National Land Transport Fund.
Far North Deputy Mayor Ann Court, whose campaign for a roundabout started 30 years ago, said the cost had gone up as the project morphed into ''an entire township plan'' with a link to Klinac Lane, parking, footpaths and a total stormwater system renewal.
''Nine million dollars was the original engineer's estimate for a roundabout. Through community consultation and working with Waipapa businesses it grew to what it is. The project grew and so the price grew.''
Court was delighted with the way the roundabout was shaping up.
''I love it, I could kiss the hot mix. You can't wipe the smile off my face.''
However, the disruption had been tough on Waipapa businesses and she encouraged Northlanders to keep supporting them.
Waka Kotahi NZ Transport Agency project manager Andrew Thackwray said the original budget was based on a business case for a relatively simple roundabout.
During the design and consenting process it evolved into a more complex project with a better outcome for the Waipapa community and local economy.
As well as the new roundabout, the project would link Klinac Lane to Maritime Lane and Waipapa Loop Rd, so people travelling between Waipapa's two commercial areas could do so without having to use the highway.
It included a new bridge on Maritime Lane, a major upgrade of water mains and the stormwater system, improvements to Waipapa Rd, walking and cycling paths, and a carpark on Waipapa Loop Rd.
An accelerated work programme, to make up for Covid-19 delays and ensure the roundabout was finished by Christmas, had also increased costs.
Contractors will down tools during the Christmas break and start on the Klinac Rd link in mid-January. The entire project is due to be completed in April.
The costs are being met by central government, not the council.
Completion of the roundabout won't mean an end to roadworks on SH10, however.
In a separate project starting in late January or early February the footpath will be extended to a planned sports hub further south on SH10. The footpath was one of the consent conditions for the new sports complex. The site entrance will also have to be shifted and upgraded.
That work is funded by a separate PGF grant of $2m for sports complex earthworks and infrastructure.