SH1 Mangamuka Gorge emergency work complete - slip repair work begins

Kia ora koutou,

With the emergency protection work now complete, permanent works for slip repairs at SH1 Mangamuka Gorge have now begun.

While further information on the timeline for re-opening SH1 Mangamuka Gorge will be available by the end of next month, multiple work streams are happening in parallel to ensure that the critical route can be reopened as soon as possible. This includes:

• Mobilising work crews and equipment
• Fnishing the final pieces of emergency protection work
• Finalising the detailed slip repair designs
• Optimising our work programme to expand our resources and get work completed quicker
• Investigating longer term resilience solutions
• Continuing to carry out regular surveying, drilling and geotechnical investigations to ensure we stay on top of any changing conditions within the gorge.

We’re finalising the detailed slip repair designs as well as optimising our work programme while physical work on site is beginning,

Reconnecting Far North communities at this location is our priority. The work we’re doing now will mean slip repair construction can run as safely, smoothly and quickly as possible.

We know communities are eager to understand when the gorge will reopen, and we will share a timeframe as soon as we have it confirmed.

We are investigating how we can make more resources available in terms of crews, work sites and shifts which would accelerate the work.

Physical works details

We have awarded the construction contract to CLL through an accelerated procurement process and the contractor is now mobilising equipment and setting up their work site in the gorge.

The first month of work will be focussed on ensuring the gorge is safe and stable enough to accommodate the large machinery needed to carry out slip repairs.

This includes installing piles, stabilising the road throughout the site as well as retaining and strengthening areas and will complement the completed emergency work protecting the gorge from further damage. This has included crack sealing, installing bunds and culverts as well as drainage and stabilising work.

Longer-term resilience planning

In parallel to the slip repairs, Waka Kotahi is investigating how the road can be improved and futureproofed to ensure the Far North roading network can withstand weather events in the future.

We are thinking strategically about our next steps and will investigate how we can ensure the Far North roading network can stand the test of time, and the level of funding required to achieve this.

We’ll be investigating this from a national perspective, as many parts of the State Highway network will be challenged with resilience issues in future due to climate change. This work is especially important given recent weather events.

We will continue to keep Far North communities updated as the work progresses and will collaborate with community representatives, experts and hapū about decisions on next steps.

More information

For more information on the SH1 Mangamuka Gorge slip repairs, contact us at northlandproject@nzta.govt.nz

Visit our website www.nzta.govt.nz/mangamuka