National says it is “ridiculous” that nearly $80 million has been spent as part of a safety improvement programme on the notorious Dome Valley section of State Highway 1 north of Auckland since 2019 yet none of it related to increasing resilience to future weather events.

It comes as the critical road linking Auckland and Northland is closed for a third day after major slips. It follows two other closures already this year due to slips - one in February after Cyclone Gabrielle lasting 76 days.

The latest closure has forced large trucks to take to small back roads - resulting in queues of up to 100 vehicles, with drivers reporting having to take evasive action to avoid hitting oncoming traffic in places.

The latest slip had seen at least 30 truckloads worth of debris spill onto the road, and helicopters were deployed to transfer water onto the slip in what is called sluicing, which washes the material off the top to break it up and prevent further slips.

Waka Kotahi/NZ Transport Agency has confirmed to the Herald that work is now under way to improve resilience in the short, medium and long term - a project dubbed the Dome Valley Strategic Resilience Response - but currently without a timeframe nor dollar figure, and still awaiting board approval.

The Dome Valley section of State Highway 1 from Wellsford to north of Warkworth has been part of the Government’s $1.4 billion Road to Zero Programme of safety improvements across the country.

Work began in September 2019 and ended last year on the highly-used stretch of road including widening the centre line and roadside shoulders, adding right-hand turn bays and installing flexible road safety barriers.

According to Waka Kotahi, the 15.2km stretch of road had a “poor safety record”. Seven people had died and more than 30 were seriously injured in road crashes in the Dome Valley in the five years prior to the project commencing.

Data released to the National Party showed since May 2013 there had been 16 road closures in the Dome Valley due to major crashes, lasting up to 10 hours. There have been none since March 2022.

However, since then have been eight closures due to road works, maintenance and repairs, all totalling multiple days at a time - the longest nearly 22 days.

On top of this have been three weather-related closures, the longest at just over 76 days after Cyclone Gabrielle.

National Party transport spokesman Simeon Brown said it was “ridiculous” that nearly $80m had been spent on the important corridor with none of it committed to improving resilience “despite known risk”.

Brown also criticised the Government’s decision to not extend the Pūhoi to Warkworth highway through to Wellsford, as National had originally planned. Labour opted instead to spend money on safety improvements.

“It would have made it much safer and far more resilient but they decided to cancel that upgrade and build the Auckland light rail instead, which has failed.

“Northlanders are now facing the consequences of being cut off regularly.”

Brown said it was “very shortsighted” the Government had spent so much money on safety improvements, some of which would have been taken out in the slips.

“Northland has been cut off for a significant amount of time this year. It affects productivity and locked out Northlanders.”

Transport Minister David Parker, who took over after Michael Wood quit last week over a shares scandal, declined to comment.

A Waka Kotahi spokesperson said the $80m spent was for the Dome Valley safety improvements project.

This included putting in median barriers, widening the road, minor stormwater improvements and retaining structures for the widened road.

They said there was resilience work happening in the valley, including stabilising overslips and underslips and stormwater drainage.

When the Herald pointed out that this was reactive and not proactive resilience work, the spokesperson said a Whangārei to Dome Valley Strategic Resilience Response (SRR) project was under way in response to the recent weather events.

“The SRR will consider short, medium, and long-term options to achieve appropriate future levels of service and resilience for the roading network between Whangārei and Warkworth.”

The SRR was due to go to the board later this year and there was no dollar figure on this yet, they said.

Meanwhile, Waka Kotahi’s regional manager of maintenance and operations Jacqui Hori-Hoult on Wednesday was reminding motorists that the official detour route for northbound traffic is from Pukerito roundabout, right to Old SH1 through Warkworth, right to Woodcocks Rd, on to West Coast Rd and right to SH16 - and in reverse for southbound traffic.

Alternatively, motorists could also use SH16 from Wellsford.

Michael Neilson is a political reporter based at Parliament in Wellington. He joined the Herald in 2018 and has covered social issues, the environment and Māori affairs