State Highway 2 in Wellington was blocked northbound from Melling for several hours yesterday due to a slip. Photo: Waka Kotahi/Supplied
Wellington contractors are today assessing the sites where landslides caused two state highways to close yesterday.
The southbound lanes of State Highway 59 in Porirua and the northbound lanes of State Highway 2 in Lower Hutt were both closed for hours after heavy rains lashed the region, causing landslides and felling trees. Both roads closed mid-morning and were not reopened until late yesterday afternoon.
Waka Kotahi Wellington maintenance and operations manager Mark Owen said it was likely more work would be needed.
He said the roads were checked before being reopened yesterday and monitored after that, but geotechnical engineers would today conduct more detailed assessments.
"They'll look at what the permanent repair might be, whether we need to do anything significant in terms of slope stabilisation and certainly in terms of protection of the slope itself," he said.
"The risk is once you get a slip, then you get an exposed area so we need to make sure we can re-vegetate it or retain it so that it doesn't cause an ongoing problem."
The southbound lanes of State Highway 59 in Porirua were closed for hours on Sunday 27 November 2022 after heavy rain caused a slip. Photo: Waka Kotahi New Zealand Transport Agency
Photos on social media showed a house perched precariously on the top of the State Highway 2 slip, near the Melling interchange, but the Hutt City Council confirmed no one was evacuated.
Owen told Morning Report engineers would be doing a detailed assessment of the damage and Waka Kotahi would work with the adjacent property owners to work out permanent solutions.
"There's still debris and silt and bits and pieces so our crews will be out cleaning up where they need to but there will be ongoing work behind the barriers" - Waka Kotahi Wellington maintenance and operations manager Mark Owen
Traffic in both areas should flow "OK" today, he said.
"We just advise people, please, the surface is still very greasy.
"We've had a lot of water over the Wellington highways the last 24 hours.
"There's still debris and silt and bits and pieces so our crews will be out cleaning up where they need to but there will be ongoing work behind the barriers."
Owen said the slips were considered "moderate" but there was still work to do to make it safe for road users as well as property owners.
Local councillor Brady Dyer said it was a stark reminder of the effects of climate change and shifting weather patterns.
"We're seeing more and more of these sorts of slips around the region," he said.
Emergency workers inspect house where part of hillside has slipped away in Hutt Valley. Photo: Brady Dyer
In July, two large slips near the entrance to Stokes Valley cut off direct access between the suburb and central Lower Hutt, and caused two families to evacuate their homes.
"It's definitely a concern for people, both for residents directly affected - you've got to remember that there's people's homes and livelihoods at the top of most of these slips - but also just the disruption it has to the traffic network," Dyer said.
"We had over 200 slips a couple of weeks ago in the space of a few weeks and we've still got a huge disruption on Eastern Hutt Road with the slips there, they've still taken out one lane of southbound traffic."