Last updated: Tuesday 16 April 2019.
- What happened to the Waiho River bridge?
- What is a Bailey bridge?
- Why is a Bailey bridge used over the Waiho River?
- How long did it take to replace?
- What traffic will be allowed to use the Bailey bridge when it is installed?
- Can I reach Fox Glacier from Franz Josef via SH6?
- How can I stay updated on which roads are open?
- Can I access the Fox and Franz Josef Glaciers?
- Why not put two Bailey bridges side by side to improve traffic flows?
What happened to the Waiho River bridge?
The Waiho River bridge on SH6 south of Franz Josef was washed away during the deluge on Tuesday 26 March 2019. The area where the bridge meets the northern riverbank scoured out, and then the pier closest to this collapsed – most likely because of a significant debris strike. Once the deck fell into the water the current took hold and pulled more of the bridge into the river.
What is a Bailey bridge?
A Bailey bridge is a modular form of bridge system that is versatile and relatively quick to erect. It can be used on a temporary or semi-permanent basis. You can find out more information about Bailey bridges at www.nzta.govt.nz/bailey-bridges
Why is a Bailey bridge used over the Waiho River?
The Waiho River is a challenging and constantly changing environment, with a riverbed level that fluctuates due to large volumes of gravel being washed down the river from the surrounding valleys. A Bailey bridge was installed on a semi-permanent basis as it can be raised to accommodate the unstable nature of the riverbed. The previous Bailey bridge had been lifted several metres since 1990 because of rising riverbed levels.
How long did it take to replace?
The bridge reopened for traffic at midday on Saturday 13 April, just over two weeks after replacement work began. The rapid opening was possible thanks to the tireless efforts of NZ Transport Agency staff, multiple contractors, NZ Defence Force (NZDF) engineers and designers, and the supportive community of South Westland.
What traffic will be allowed to use the Bailey bridge when it is installed?
The new single-lane bridge will take all vehicles categorised as Class 1, including heavier trucks, not just cars and buses as originally planned.
Can I reach Fox Glacier from Franz Josef via SH6?
Yes. The Waiho bridge is now open, but as additional construction is still taking place on the bridge, please expect some delays to your journey.
View our Journey planner website for highway conditions on this route.(external link)
How can I stay updated on which roads are open?
As this situation is rapidly changing, please follow NZTA on twitter and Facebook for the most recent updates. You can also check these West Coast and Otago links for further updates and changes:
www.journeys.nzta.govt.nz/traffic/west-coast(external link)
www.journeys.nzta.govt.nz/traffic/otago(external link)
Can I access the Fox and Franz Josef Glaciers?
Yes, but because access roads and walking tracks to the glaciers have been damaged by the flooding, currently the only access to the glaciers is via helicopter. Glacier flight operations are still open and operating at both Franz Josef and Fox Glaciers.
Why not put two Bailey bridges side by side to improve traffic flows?
There are minimal traffic delays caused by having a one-lane bridge across the Waiho River, and little economic justification to warrant a second one. Besides the cost of a bridge itself, a second bridge would require a whole new run of bridge piers and support – there is currently only one line of piers and abutments. Installing a second bridge would also put major pressure on Bailey bridge stocks, limiting our response during emergency situations elsewhere.
