The Country
  • The Country home
  • Latest news
  • Audio & podcasts
  • Opinion
  • Dairy farming
  • Sheep & beef farming
  • Rural business
  • Rural technology
  • Rural life
  • Listen on iHeart radio

Subscriptions

  • Herald Premium
  • Viva Premium
  • The Listener
  • BusinessDesk

Sections

  • Latest news
  • Coast & Country News
  • Opinion
  • Dairy farming
  • Sheep & beef farming
  • Horticulture
  • Animal health
  • Rural business
  • Rural technology
  • Rural life

Media

  • Podcasts
  • Video

Weather

  • Kaitaia
  • Whāngarei
  • Dargaville
  • Auckland
  • Thames
  • Tauranga
  • Hamilton
  • Whakatāne
  • Rotorua
  • Tokoroa
  • Te Kuiti
  • Taumurunui
  • Taupō
  • Gisborne
  • New Plymouth
  • Napier
  • Hastings
  • Dannevirke
  • Whanganui
  • Palmerston North
  • Levin
  • Paraparaumu
  • Masterton
  • Wellington
  • Motueka
  • Nelson
  • Blenheim
  • Westport
  • Reefton
  • Kaikōura
  • Greymouth
  • Hokitika
  • Christchurch
  • Ashburton
  • Timaru
  • Wānaka
  • Oamaru
  • Queenstown
  • Dunedin
  • Gore
  • Invercargill

NZME Network

  • Advertise with NZME
  • OneRoof
  • Driven Car Guide
  • BusinessDesk
  • Newstalk ZB
  • Sunlive
  • ZM
  • The Hits
  • Coast
  • Radio Hauraki
  • The Alternative Commentary Collective
  • Gold
  • Flava
  • iHeart Radio
  • Hokonui
  • Radio Wanaka
  • iHeartCountry New Zealand
  • Restaurant Hub
  • NZME Events

SubscribeSign In
Advertisement
Advertise with NZME.
Home / The Country

Northland storm: Slip that closed Mangamuka Gorge could take 6 weeks to clear

Northern Advocate
2 Aug, 2020 11:00 PM3 mins to read

Subscribe to listen

Access to Herald Premium articles require a Premium subscription. Subscribe now to listen.
Already a subscriber?  Sign in here

Listening to articles is free for open-access content—explore other articles or learn more about text-to-speech.
‌
Save

    Share this article

A large under-slip has undermined State Highway 1 in the Mangamuka ranges south of Kaitaia with the transport agency unable to say when the road will reopen.

A large under-slip has undermined State Highway 1 in the Mangamuka ranges south of Kaitaia with the transport agency unable to say when the road will reopen.

A large slip below State Highway One at the Mangamuka Gorge has left roading authorities unsure when the road through the gorge will reopen, but it could take six weeks.

A series of slips closed SH1 through Mangamuka Gorge overnight on July 17/18 when a storm dumped 220mm of rain - about two months worth - in a few hours.

Waka Kotahi NZ Transport Agency says it's still too early to say when SH1 through the gorge could be opened to traffic.

Most of the road has been cleared to at least one lane, but there's still no way past the biggest slip on the northern side of the gorge. The hillside under the road fell away during the heavy rain two weeks ago, leaving metres of road surface suspended in the air.

Waka Kotahi Northland System Manager Jacqui Hori-Hoult said safety was a priority as her team assessed the slip and the repair job needed to reopen the road.

Advertisement
Advertise with NZME.
Advertisement
Advertise with NZME.

"Six to seven thousand cubic metres of material has fallen from under the road to the river below. What's left is brittle and unstable and our concern is that more heavy rain could bring down more of the hillside,'' Hori-Hoult said.

"A further complication is that there's a historic slip directly above the road and we have to be very careful about disturbing the slope. We need to further investigate the slope to develop our longer-term road repair options.

"The good news is that there's been only light rain since the slip. Our geotech experts are working to understand the soil conditions and locate stable bedrock before deciding on the safest and most effective solution for restoring the road."

Advertisement
Advertise with NZME.

READ MORE:
• Once-in-500-year storm floods Northland, traps residents
• Northland floods: No hope for drying out in storm-hit Far North
• Northland storm: Some roads still closed after slips and flooding cause major damage
• Torrential rain in Northland closes highways, floods homes

The plan is to work in stages to open the road, initially to a single lane so that light vehicles can get past. Weather permitting, that may take six weeks.

Elsewhere in the gorge, other slips have been cleared and, with safety barriers and other precautions in place, the road is ready for light vehicles.

A large under-slip has undermined State Highway 1 in the Mangamuka ranges south of Kaitaia with the transport agency unable to say when the road will reopen.
A large under-slip has undermined State Highway 1 in the Mangamuka ranges south of Kaitaia with the transport agency unable to say when the road will reopen.

"Waka Kotahi acknowledges the inconvenience and cost to local communities on either side of the gorge of having to use the longer SH10 detour. We're working to reopen the road as safely and as quickly as we can," she said.

Discover more

Major slip at Dragonfly Springs Wetland Sanctuary

23 Jul 10:00 PM

Northlanders still being asked to conserve water

23 Jul 07:00 PM

Northland's July 2020 flood in photos

23 Jul 04:32 AM

Whangārei Hospital kauri tree attack

24 Jul 06:00 PM

On average, about 1300 vehicles a day travel on SH1 through the Mangamuka Gorge. It will be some time before trucks and buses can travel the road.

For now, SH1 through the Mangamuka Gorge is closed between Victoria Valley Rd and Makene Rd. SH10 is the detour with motorists advised to allow an extra 20-30 minutes for their journey.

The estimated cost of the storm response and repairs to Northland's state highway network to date is $5.9 million. This did not include the final repair costs for the Mangamuka Gorge, Hori-Hoult said.

Save

    Share this article

Latest from The Country

The Country

'A lot of fun': Planting project rewarding for farming couple

14 Jun 05:01 PM
The Country

Why every garden needs a persimmon tree

14 Jun 05:00 PM
The Country

Farming, science and family through the generations

14 Jun 05:00 PM

It was just a stopover – 18 months later, they call it home

sponsored
Advertisement
Advertise with NZME.

Latest from The Country

'A lot of fun': Planting project rewarding for farming couple

'A lot of fun': Planting project rewarding for farming couple

14 Jun 05:01 PM

“We’d like to thank everyone who has helped us with potting up seedlings & planting out."

Why every garden needs a persimmon tree

Why every garden needs a persimmon tree

14 Jun 05:00 PM
Farming, science and family through the generations

Farming, science and family through the generations

14 Jun 05:00 PM
'Not suitable for high speeds': Rural roads in the 1930s

'Not suitable for high speeds': Rural roads in the 1930s

14 Jun 05:00 PM
The woman behind NZ’s first PAK’nSAVE
sponsored

The woman behind NZ’s first PAK’nSAVE

NZ Herald
  • About NZ Herald
  • Meet the journalists
  • Newsletters
  • Classifieds
  • Help & support
  • Contact us
  • House rules
  • Privacy Policy
  • Terms of use
  • Competition terms & conditions
  • Our use of AI
Subscriber Services
  • NZ Herald e-editions
  • Daily puzzles & quizzes
  • Manage your digital subscription
  • Manage your print subscription
  • Subscribe to the NZ Herald newspaper
  • Subscribe to Herald Premium
  • Gift a subscription
  • Subscriber FAQs
  • Subscription terms & conditions
  • Promotions and subscriber benefits
NZME Network
  • The New Zealand Herald
  • The Northland Age
  • The Northern Advocate
  • Waikato Herald
  • Bay of Plenty Times
  • Rotorua Daily Post
  • Hawke's Bay Today
  • Whanganui Chronicle
  • Viva
  • NZ Listener
  • Newstalk ZB
  • BusinessDesk
  • OneRoof
  • Driven Car Guide
  • iHeart Radio
  • Restaurant Hub
NZME
  • About NZME
  • NZME careers
  • Advertise with NZME
  • Digital self-service advertising
  • Book your classified ad
  • Photo sales
  • NZME Events
  • © Copyright 2025 NZME Publishing Limited
TOP