Whakawhirinaki Silverstream Pipe Bridge | Steel Birds (2025)

Collaborators:

• Artist: Len Hetet

• Client: Wellington Water

• Mana Whenua: Te Ātiawa

• Bridge Architects: Boffa Miskell

• Main Contractor: Brian Perry Civil

• Engineers: Clendon Burns & Park

• Fabricators: Steel E.D & Patton

• Steel Supply: Real Steel

• Creative Production Partner: Human Dynamo Workshop

The brief

Wellington Water’s Silverstream Pipe Bridge crosses Te Awa Kairangi (Hutt River), connecting Fergusson Drive to SH2 at Silverstream. The pipe bridge was built to improve the resilience of drinking water supply to Upper Hutt, Stokes Valley and  Porirua, and is one of the regions most critical water supply pipelines. The bridge, which also has walking and cycleways, was gifted the name Whakawhirinaki by local iwi.

Wellington Water commissioned artist Len Hetet (Te Ātiawa Taranaki Whānui) to design artworks for the bridge to enhance the environment and improve the experience of people using it. Len envisioned large sculptural birds — bold, corten-steel forms standing as welcome markers on the bridge. They symbolise connection, kaitiakitanga, and the area’s rich resources. Human Dynamo Workshop was engaged to help bring this ambitious concept to life.

The challenge

Turning a 25-centimetre cardboard model into seven-metre-tall steel sculptures required significant creative engineering. For the project to be a success, we needed to:

• Source heavy-gauge corten steel in small enough quantities for the job.

• Engineer the large, slender forms to withstand wind, weight, and code requirements without compromising the artistic intent.

• Orchestrate the work of multiple parties under a tight schedule and within the existing infrastructure programme.

• Uphold cultural and aesthetic integrity while navigating the practical demands of a major public works project.

This required a partner who could navigate both the creative and technical worlds, bringing together the right people, processes, and materials to ensure the artist’s vision could stand proudly and safely in the landscape.

Process & Approach

From the outset, Human Dynamo Workshop acted as the project’s creative production partner, guiding the translation of Len Hetet’s artistic vision into a structurally sound and buildable reality. Our role wasn’t fabrication, but orchestration: bringing together the right expertise, materials, and technical processes to honour both the creative and cultural intent of the work.

Using Len’s vector artwork and handmade maquette, our team built a precise 3D CAD model, refining proportions and patterns in close consultation with Len. We led the prototype engineering, working alongside structural engineers to ensure the sculptures met safety and durability standards while keeping the creative integrity intact.

When the right corten steel proved difficult to source (suppliers required 10-tonne minimum orders for what was only a 1.5-tonne job) we explored a hybrid solution using galvanised mild steel with corten skins. But by chance, Real Steel offered offcuts from a previous bridge project, allowing a return to the original all-corten design. The design was then adapted to fit the available off-cuts. This is a testament to our agility, resourcefulness, and dedication to material authenticity.

Throughout, Human Dynamo Workshop acted as a bridge between artists, engineers, and contractors, producing detailed digital documentation, transport and installation plans, and on-site support. Our team’s unique blend of design and engineering fluency ensured seamless communication across disciplines and smooth integration with the main bridge building work.

Result & Impact

Two striking seven-metre corten steel bird sculptures now stand proudly at either end of the Silverstream Pipe Bridge, their dramatic tails arching upward like a waharoa (gateway). Visible from afar, they anchor the bridge in the landscape and mark a powerful collaboration between art, engineering, and culture.

The birds are more than public art. They are a symbol of partnership and place. For Te Ātiawa Taranaki Whānui, they represent an enduring connection to Te Awa Kairangi and kaitiakitanga over the whenua. The artworks’ long-term maintenance is now guided by the Mana Whenua governance group, ensuring their continued presence and care, with our support.

For Wellington Water and the wider design team, the project demonstrated how art can meaningfully enrich infrastructure, embedding culture and identity in public spaces. For Human Dynamo Workshop, it exemplifies the value of creative and technical stewardship, bringing together artists, engineers, and fabricators to ensure ideas of cultural significance are realised safely, authentically, and with enduring impact.