12 Oct 2020

Work begins on arterial route for capital

9:58 am on 12 October 2020

Work to reinforce areas of landslips on the Ngaio Gorge in Wellington is starting, reducing the road to just one lane.

No caption

Slips are a frequent occurrence in the Ngaio Gorge. Photo: Supplied / NZTA

It's part of an $11m project to reinforce the slip areas after the July 2017 landslides.

Wellington mayor Andy Foster said the work was expected to take up to two years to remove loose material and stabilise the latest slip, making the route between Ngaio and the city more resilient.

The road will be reduced to one lane for that time and will be controlled by traffic lights.

Foster said the work would, at times, inconvenience drivers, cyclists and pedestrians on the road but he asked them to be patient.

He said commuters should use Ngauranga Gorge, Onslow Road or public transport to help ease congestion while the vital arterial route was under construction.

In the early stages of the project, for safety reasons, cyclists will need to dismount to dismount and push their bike through the pedestrian areas of the site, particularly when travelling uphill.

Three retaining walls will be built to realign the road - taking about a year - then stabilisation work on the lower and upper slip sites and the removal of concrete barriers and shipping containers being used as barriers.

Crews will work from 7am to 6pm Monday through Saturday.

Council transport infrastructure portfolio leader Councillor Jenny Condie told Morning Report that the 2017 slip had been massive. It had taken a long time to come up with a permanent solution because the engineering had been complex and engineers needed to provide a resilient solution.

"It's a really important road. The reason we're doing this work is because it's one of our lifeline roads out of the city. If there's an earthquake, it's an alternative route to the Ngauranga Gorge."

The Ngaio Gorge slip.

Engineers inspect the slip in 2017. Photo: Wellington City Council

Condie said the the first job the construction team would tackle was removing lizards and rehoming them in Trelissick Park.

"We've been waiting for lizards to come out of hibernation. Now that they are awake we can start moving them out of harm's way before we start on this critical project.

"Each lizard will be captured individually in breathable cloth bags and transferred across the road to their new home in Trelissick Park.

"It will take three to four days to complete this inspection and relocate any lizards found.

"There's a whole bunch of procedures to try and ensure they don't get too stressed.

"Three of the types of lizards are relatively common but there are three there that we think are on the threatened list that we might be finding in this area so it is important that we find them a new home."

Wellington was a city prone to slips. "The reality of living in a hilly city is we're always going to have bits of slip coming down here and there and we're just going to have to manage that as we go."

Funding for the project is split between the Transport Agency (51 percent) and Wellington City Council (49 percent).

Get the RNZ app

for ad-free news and current affairs