TREC Tairāwhiti recovery update

Issue 30

19 September 2025

Tēnā koe

In this edition, we share exciting news about the Rototahe flood resilience work kicking off on State Highway 35 (SH35), an update on progress at our Hakanui Straight project on State Highway 2 (SH2), and you can view new drone footage of our recent work at Hikuwai Bridge (SH35).

Thanks for your continued patience as we carry out this important recovery mahi.

Flood resilience work at Rototahe gets underway

Road users travelling on SH35 to Gisborne should expect short delays as critical flood resilience work gets underway at Rototahe (south of Tolaga Bay).

TREC and local contractors are lifting a 200m stretch of SH35 through Rototahe by nearly a metre (0.83m) and upgrading drainage with new and improved culverts. These changes will help keep water away from the road and reduce closures during future weather events.

Anne McGuire of local Iwi Te Aitanga-a-Hauiti has been working alongside TREC on various SH35 projects and says having a reliable road is more than just transport, it’s about staying connected as whānau, hapū and Iwi.

“This work at Rototahe helps ensure our communities are not cut off during storms, and that lifelines for kai, medicines, and emergency services remain open. We welcome this partnership and the commitment to strengthening SH35 so our people and future generations can travel safely along the coast.”

The project is expected to take up to 6 months to complete.

Traffic impacts

A northbound section of the Rototahe straight will be under stop/go traffic management Monday to Friday from 7am to 5pm. A 30km/h temporary speed limit will be in place.

Please expect possible delays of 5-10 minutes.

For more information you can read the media release.

TREC with Iwi partners Te Aitanga-a-Hauiti and local contractors mark work starting with a karakia.

Enabling (early) works complete on SH35 Hikuwai Bridge project

TREC and local contractors have completed the first phase of works at Hikuwai Bridge with the main bridge build getting underway soon.

Building futures with Tolaga Bay Area School

A group of senior students from Tolaga Bay Area School visited the Hikuwai Bridge site on SH35 this week, keen to learn more about careers in construction and the bridge project.

Our team had the opportunity to walk them through the scope of the project, share insights on the work happening behind the scenes, and talk about the many career paths in the transport and construction sectors.

Thanks to the students and Matua Richard for visiting. We hope the visit sparked some ideas for future pathways and we look forward to welcoming them back when the action ramps up!

On the next visit, the site will look very different. Equipment, large machinery and bridge materials are scheduled to be delivered with main works planned to get underway over the next month.

Tolaga Bay Area School senior students and TREC staff on site at Hikuwai Bridge.

Mangahauini Gorge recovery: landslide removal begins

Cyclone Gabrielle triggered a massive landslide that dammed the Mangahauini River and closed SH35.

This week, Blackbee Contractors began the complex task of removing around 50,000 cubic metres of that debris, marking an important step in the recovery process.

A nearby fill site has been carefully chosen with hapū and Iwi, to ensure the displaced whenua stays in the Mangahauini Gorge. This work is expected to be finished by Christmas.

He kōrero mō te whenua (A story about the land)

For Māori, whenua isn’t just soil. “It carries whakapapa (our genealogies), mauri (its living essence), and ancestral connection (our ties to tūpuna and place)", explains TREC Pou Ārahi Na Raihania.

“That’s why landslide material from Mangahauini Gorge is being kept close to where it came from instead of being trucked away.”

It’s all go in the gorge. The team is also getting ready for the first hanbars (specially made interlocking concrete blocks that will line the new roughened channel) to arrive at site next week. We’ll share more in our next issue.

Traffic impacts

SH35 in the gorge is down to 1 lane with stop/go traffic management, lower speed limits and other traffic management in place until mid-2026. Please expect short delays when travelling through.

Find out more about upcoming work.

Around 50,000 cubic metres of landslide material, visible to the left of the river in this photo, will be removed over the coming months.

Otoko Hill progress update

Our final 2 projects on Otoko Hill (SH2) are underway.

Otoko site K is tracking well with all 19 counterfort drains installed. These play an important role to channel water away and reduce water pressure in the hills that can cause slips. The second stage of drainage work will start soon.

Site M started earlier this month, with crews busy on early works including fencing and access track construction. Both sites should be complete early 2026, weather permitting.

See the site locations.

At site M crews are repairing an underslip beneath the highway, shown here before work started.

New Hakanui stream realignment and swale taking shape

Check out this huge swale being constructed at the Hakanui Straight project (formerly called Nesbitt's Dip) on SH2 near Te Karaka.

A swale is a shallow, planted channel that slows and filters stormwater, guiding it away from the road. They help soak up water and are used around New Zealand in flood prone areas.

This swale is doing double duty. It’s also the new alignment for part of the Hakanui Stream and will connect to the new larger 1.8 metre culvert (large pipe) being installed this month.

Crews are currently shaping the swale. Parts of it will be planted out with native vegetation to help stabilise the soil and reduce erosion.

24/7 stop/go from 23 September

Crews will start installing culverts under the highway this month. While some of this work is underway the highway will be under stop/go traffic management 24/7 for around a week. Expect delays of up to 10 minutes if you’re travelling through.

Automated traffic lights – remember to wait for green

The traffic lights at this site are fully automated and wirelessly synced to let 1 direction through at a time. Driving through a red light risks a crash and throws the system out of sync, causing delays while crews reset the timing. Thanks for helping to keep the site safe and traffic flowing.

Hakanui Straight project site supervisor Ross Troughton in front of the swale and stream realignment being constructed.

Tōrere slip repairs (SH35, Eastern Bay of Plenty)

At Tōrere, Waiotahi Contractors have finished installing 32 long steel rods (called soil nails) that will anchor the hillside and repair the underslip beneath the highway. Each nail is tested before being locked in with grout.

Crews are preparing the next section of the underslip wall, connecting steel rods to a shotcrete wall (sprayed concrete) followed by pouring no-fines concrete (a porous mix that lets water drain while holding the wall firm). Built-in drainage systems will help guide water away and keep the slope stable.

TREC Site Engineer Edwin Ferrer says the overslip (above the highway), is being rebuilt using a layered wall system called MSE (Mechanically Stabilised Earth).

Each layer includes Terramesh (steel mesh baskets that are filled with rock) and geogrid (a tough net that reinforces soil) to hold the hillside in place.

A chimney drain (a vertical gravel column) is being added to help guide water away and reduce pressure behind the wall.

Did you know?
TREC uses a lot of no-fines concrete across Tairāwhiti to help stabilise flood-prone hillsides. This special mix skips the sand and uses only gravel and cement, making it porous, kind of like a sponge made of stone. It’s strong enough to hold the hillside together but still lets water escape.

The overslip is being rebuilt using a layered wall system called MSE (Mechanically Stabilised Earth).

Summer roadworks ahead

The summer construction season is nearly here, and NZ Transport Agency Waka Kotahi (NZTA) crews will soon be out across the region delivering annual maintenance, such as road rebuilds, resealing, and drainage works.

With this and TREC recovery work underway at the same time, expect more activity on the roads over the coming months.

This maintenance season, NZTA will be sending regular newsletters to keep you informed about upcoming roadworks on state highways in Tairāwhiti.

Sign up to receive them.

State highway snapshot

Below is a snapshot of construction works either underway or coming soon. You can also view completed, current and future work sites on our interactive map.

Here are some of the construction terms we use:

• Bund – embankment that creates a barrier
• Buttress – supporting structure
• Counterfort drain – drain that improves slope stability by controlling groundwater 
• Gabion wall - baskets filled with rocks
• Hanbar – specially designed interlocking blocks
• MSE (Mechanically Stabilised Earth) – a retaining wall construction technique used to stabilise slopes
• Rip rap - large rocks
• Rock revetment – protection
• Scour - erosion
• Shotcrete – sprayed liquid concrete
• Soil anchors/soil nails – a device used to hold, restrain and support structures
• Willow wall – using willows as ‘living walls’ to stabilise slips

SH2 underway

• Hakanui Straight project (formerly called Nesbitt’s Dip project) – flood improvements.
• Matawai Road – willow wall to stabilise slip.
• Otoko Hill (Site K) - overslip repairs.
• Otoko Hill (Site M) - underslip repairs.

SH35 underway

• Hikuwai Bridge No.1 replacement
• Mangahauini Gorge – river works, drainage and culvert upgrades, highway repair and rebuild.
• Kopuaroa Slip 1 – reinstate SH35 to 2 lanes by installing a soil anchor and shotcrete wall.
• Tōrere – underslip and overslip repairs.
• Paronga - D9 Gully Site – buttress wall with MSE. Two faults to be repaired to reinstate state highway to 2 lanes.
• Kemps Hill subsidence – buttress repair using a willow wall. Three faults to be repaired to reinstate state highway to 2 lanes.
• Rotokautuku (Waiapu) Bridge repairs – strengthening works.
• Rototahe – flood resilience.

SH35 coming soon

• Rotokautuku (Waiapu) Bridge revetment – scour protection.
• Rotokautuku (Waiapu) Bridge – southern end strengthening.
• Maraehara – underslip repairs.
• Uawa River Scour – Two underslips to be repaired to reinstate state highway to 2 lanes.
• Kopuaroa – drainage improvements.
• Paronga (D9) – drainage improvements.

Whakapā mai – Get in touch

• Email us
• Website
• LinkedIn
• Facebook
• Call us: 0800 80 TREC (0800 80 8732)

If you spot an issue at a work site after hours, call 0800 4 HIGHWAYS (0800 444449).

Sign-up to receive these regular newsletters:

• TREC Pānui (general newsletter)
• TREC Hawke's Bay regional update
• This TREC Tairāwhiti regional update

Local road network

Gisborne District Council is responsible for local roading recovery projects. More information.

Up-to-date information on local road closures.