The use of PeterFell’s Black Oxide in the construction of the Te Ara Tupua, a shared path to improve the resilience of the critical transport corridor between Wellington and Lower Hutt, was designed, in part, to appeal to a special group of locals.
The locals in this case being Kororā (Little Blue Penguins), Shags, Herons and other assorted bird and sea life.
“It’s important that the local wildlife isn’t negatively impacted and is comfortable with the new man-made structure,” says PeterFell Regional Manager Stu Hunter.
No mean feat when you consider that said structure, when completed in 2026, will include approximately 144,000 tonnes of rock, and 6,672 custom-made pre-cast concrete XBloc® and Eco-enhanced XBlocPlus® units stretching over 4.5 kilometres of coastline.
Te Ara Tupua is a New Zealand Transport Agency (NZTA) Waka Kotahi funded resilience project delivered in partnership with Taranaki Whānui ki te Ūpoko o te Ika and Ngāti Toa Rangatira (iwi mana whenua), Alliance construction partners Downer NZ Ltd and Heb Construction Ltd along with design partners Tonkin + Taylor. The project will improve transport resilience by protecting the state highway and main railway line from coastal storms and the effects of future sea level rise and earthquake risk.
The concrete XBlocs (each of which weighs in at an impressive 2.6 tonnes) have been designed to interlock and stack on top of each other – a much faster and safer process than creating a wall using irregular shaped boulders (which were in short supply anyway).
Cultural designs with coinciding environmental benefits were precast onto the XBloc® units. These changes modified to XBlocPlus® to align with the area’s history and natural character of the landscape, while also meeting environmental permits with no increases to the cost envelope. Iwi Design Lead Len Hetet worked alongside project designers, engineers, and ecologists to create the unit’s surface, which mimics the rocky foreshore and enables 4000m2 of increased complexity for marine growth.
Hetet gifted the name ‘Te Ripowai’ to the unit, expressing a cultural narrative and iwi whakataukī of guardianship over the rippling water.
‘We as guardians must keep the ripples occurring; if we do not, and the water becomes still, then life will cease to exist.’
– Len Hetet.
The environmental narrative is further enhanced with PeterFell Black Oxide.
Rather than the stark, bright-grey of natural concrete, the Black Oxide pigment creates rich, earthy tones that echo the hues of the harbour’s basalt and black sand.
“These darker tonings help the XBloc® and XBlocPlus® units to visually recede into the landscape and preserve the natural look of the coast,” Hunter explains. This is to encourage native wildlife to return once the project is completed, two offshore habitats specifically designed to support bird roosting, are also part of this initiative.
“We’ve used two different dosages of the colour for visual interest, creating darker and lighter shades of black along the coastline,” Hunter says.
The oxide is mixed all the way through the concrete so will maintain its distinctive look despite the pounding of the waves.
Black Oxide also features in the bridge decks, viewing platforms and shared pathway, unifying the visual language across the entire development.
“Sustainability has always been a strong part of the PeterFell narrative, so we’re really proud to be associated with projects like Te Ara Tupua” Hunter explains.
PeterFell’s Black Oxide, for example, carries an internationally recognised, independently verified Environmental Product Declaration (EPD), which clearly shows the environmental footprint of the oxide’s entire life cycle.
We have an extensive range of colour options available, plus you can order free samples to help you make your final decision.
Credits
Iwi Design Lead: Len Hetet
Project: NZTA Waka Kotahi
Photography: NZTA Waka Kotahi
Cultural narratives and design included in this communication remain the copyright of the creators and permission is required for reuse. Please contact Te Ara Tupua at tearatupua@nzta.govt.nz with any requests.
