Contractors are replacing about 7 per cent of the the bottom asphalt layers. Photo / Mark Mitchell
Part of the Peka Peka to Ōtaki expressway is being ripped up before the road has even opened because bottom asphalt layers have not met quality standards.
It comes as the road's opening remains on somewhat of a knife edge, between Covid-19, supply chain issues, and wet weather.
Although Waka Kotahi NZ Transport Agency maintains the road is still expected to open by the end of the year.
A bypass of Ōtaki, the road will join up with the existing Kāpiti expressway to the south and eventually the planned Ōtaki to north of Levin expressway.
The roads, along with the newly opened Transmission Gully motorway, form Wellington's northern corridor.
Waka Kotahi infrastructure delivery regional manager Jetesh Bhula told the Herald contractors were replacing about 7 per cent of the bottom asphalt layers.
"This is being done for quality reasons as the sections laid did not meet the required quality specifications, and would not have achieved the design life required."
Bhula said the problem was first identified on the 13km expressway in November last year.
Such issues were managed by the contractor as part of its quality control process and Waka Kotahi did not expect the remedial works to affect the project's overall cost, Bhula said.
The road is forecast to cost $445 million.
Bhula said the remedial works were included in the current programme, and the expressway was still expected to be open by the end of the year.
But he said progress has been affected by a range of issues, like other large projects in New Zealand.
"This includes a number of our people having to isolate with Covid-19, the delivery of materials being held up by Covid-19 supply chain issues and the recent wet weather.
"We're working hard to mitigate these delays."
The four-lane expressway, which started construction in 2017, was meant to open in 2020.
Then it was delayed due to an upgrade of the road's surface with a new pavement design, as well as the addition of a 10km shared path for cyclists, horse-riders. and pedestrians.
The road was rescheduled to open in 2021, but then Covid-19 hit and in June last year Waka Kotahi advised it would be delayed until late 2022.