The demolition of a cyclone-wrecked bridge at Waikare gorge between Napier and Wairoa is due to begin today.
A temporary bailey bridge opened to traffic in May, reconnecting State Highway 2 after the concrete bridge collapsed and was washed away during Cyclone Gabrielle.
Waka Kotahi said Transport Rebuild East Coast (TREC) contractors would be on site for at least five weeks, from 7am to 6pm Monday to Saturday.
They will use diggers and concrete crushers to demolish the concrete spans and old piles, before the material is removed from the river and trucked away to a local processing facility.
The work would mostly be carried out in the river and off to the side of the road, meaning any impact on traffic flow will be minimised.
The one-way bailey bridge was controlled by stop-go traffic lights, which would continue around the clock.
Waka Kotahi said road users could expect delays of around 10 minutes as the demolition equipment and crew move on and off site.
The old Waikare Gorge bridge following Cyclone Gabrielle. Photo: Waka Kotahi
TREC project director Tony Gallagher said the removal of the old bridge was an important part of the recovery of the road through the gorge, while a permanent solution was confirmed.
"The concrete piles and bridge spans present a risk that they could restrict the flow of the Waikari River during extreme weather events.
It had taken time to plan the demolition to ensure it was done as safely and as efficiently as possible, Gallagher said.
The first phase of the demolition was to remove material and debris built up at the base, which had contributed to the bridge's collapse.
Longer term, a permanent 160m bridge will be built as part of the gorge realignment project, bypassing four kilometres of the existing State Highway.
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