Ashburton River Bridge on State Highway 1. PHoto / Supplied
Ashburton River Bridge on State Highway 1. PHoto / Supplied
OPINION
Earlier this week, our Council officially lodged a detailed business case for constructing a second road bridge over the Ashburton River with Waka Kotahi NZTA.
The proposed bridge might pale in comparison to other big water crossings that have made headlines in the past few years, but it is of huge importance for the people who live in Ashburton and for every business in the country that relies on road transport to get their goods around the South Island.
When the existing State Highway 1 bridge over the river is closed, the only alternative is an 80km detour – and if it's a flood that has closed the bridge, then you can be sure the alternative route will almost certainly be washed out too.
All of this was proved in the 2021 May floods when the bridge was damaged and closed for several days. Dunedin supermarkets had empty shelves because supply trucks couldn't get past Ashburton.
Ashburton District Council Chief Executive Hamish Riach. Photo / Supplied
Closer to home, our community was effectively split into two, with people from the suburb of Tinwald cut off from police, fire and hospital services in the main part of town. People couldn't get to their places of work, kids to their schools, and families were disconnected.
Over the past few decades, locals have often worried about what would happen if the only bridge in town was to close. Plans were already on the drawing board for a second bridge and now our detailed business case is with Waka Kotahi.
The board of the national transport agency will consider our case for funding in November and it's likely to be competing against many other transport projects around the country.
However, we see this project as nationally significant. We know how crucial this bridge is to improving connectivity, not just between Ashburton and Tinwald, but for the whole of the South Island. The existing bridge opened in 1931 and now carries 24,000 vehicles a day. Even a minor traffic incident can see lines of traffic stretching kilometres beyond the town limits.
As for the hard numbers, the total cost of the new bridge is estimated at $113m if built today. Council has a contribution of $7.5m in its plans.
The business case suggests a Waka Kotahi subsidy of 62 per cent is justified, although the council has indicated a higher subsidy rate should be applicable because the new bridge will take pressure off the current State Highway bridge and improve the connectivity of the whole South Island.
We have contemplated the likely scenario that there will be a shortfall in funding and no doubt our Mayor and Councillors will be calling on those politicians, including the Prime Minister and Minister of Transport, who saw the carnage last year and encouraged us to touch base once the detailed business case was complete.
This case provides evidence that the need for a second bridge is a resilience issue greater than anywhere else in the region – and with major weather events like flooding already more common, there is increased potential for future closures or bridge failure.
It's something to think about the next time you pass through Ashburton, or if you have goods being transported that have to be delivered on time.
We know we're not alone in trying to make our district more resilient. Our thoughts are with those people who have been flooded in this past month as Mother Nature gives us a sign of what is to come.
It's clear that future-proofing our vital transport links for a more turbulent world must be a priority.
