Transport Minister and contractor give SH25A update as site is prepared for new viaduct bridge

An artist's impression of the new bridge reconnecting SH25A in the Coromandel. The project is expected to be finished by March. Photo / Waka Kotahi

Minister for Transport and the Environment David Parker was joined at the SH25A Taparahi Bridge Construction site on Friday by Workplace Relations and Safety Minister Carmel Sepuloni, Thames Coromandel District Council (TCDC) Mayor Len Salt and Coromandel MP Scott Simpson to provide an update on the project that aims to reconnect the highway to major tourist hubs.

After heavy rains created cracks on the highway on 15 January this year, further inclement weather from the Auckland Anniversary Weekend rainfall event on 27 January caused the road to be closed, before it gave way sweeping away a 60-metre section of the road.

Damage from Cyclones Hale and Gabrielle, aggrandized the gap to about 110 metres, and the destruction cut off access to the eastern Coromandel Peninsula at the summit of State Highway 25A at Taparahi, around 10km from Kopu south of Thames.

In May, former Transport Minister Michael Wood announced Waka Kotahi NZ Transport Agency’s preferred option was to replace the missing section with a bridge, saying it would be the” the fastest, most resilient way forward.”

Rebuild costs were estimated to cost $30-40 million, with completion set for early 2024.

Coromandel MP Scott Simpson, Workplace Relations and Safety Minister Carmel Sepuloni, Hugh Milliken, Project Director MᶜConnell Dowell and Thames Coromandel District Mayor Len Salt at the SH25A Taparahi rebuild site.

David Parker reaffirmed today the project was on track for a March 2024 completion, but said the cost would come within the “50 million target” which, if accurate, is a blowout of at least $10 million from the originally quoted figure.

“This is an enormous project and they (the contractors McConnell Dowell) are going to deliver it by March next year. They’ve really rattled their daggs to get this under way, and I’m impressed how they are delivering this so quickly using existing designs and bringing materials from around the country. They’ve got people working 24 hours a day assembling the girders that go on top of the piles and (holes for) abutment piles on the other side have been drilled, " Parker said.

Piles have been installed in anticipation of a new bridge at Taparahi on SH25A.

Mayor Len Salt spoke of the enormity of the job: “I was up here shortly after this slip happened and the scale was absolutely incredible, and to see the project under way is really good for our community.”

Salt praised the Government and Waka Kotahi for “getting things moving to this stage,” and added that council was “looking forward to getting this done and open again.”

McConnell Dowell’s Hugh Milliken, the site’s project director, gave updates on the work undertaken at the site by up to 50 contractors, a number expected to rise to around 100 personnel who will work over a 24-hour cycle in the coming weeks.

Milliken said that currently “there is a lot of site stabilisation going on” to prepare the area was the bridge’s installation and noted that off-site fabrication of the bridge was under way.

He intimated time is of the essence:

“We are effectively in a race to prepare the site to take heavy equipment to actually assemble the bridge. We have piling works under way which are fundamental to support the bridge.”

The piles are at a depth of around 35 metres, and Milliken spoke of the challenges of building on an area based on top of modified soft rock comprised of eroded material loosened by recent deluges adding to material from the road’s original construction in the 1970s.

“The site still has all of that modified stuff on top of it, and what we know now is when this was built, it was built using fill - most of that was modified. They pushed it in here, compacted it and a road was built under it and it survived 50 years.”