An impression of the bridge that would have 'disrupted' the rebuild, had it been built.

Some bright students designed an innovative Christchurch bridge that looks like an eel trap. But sadly, it won't be built. Philip Matthews reports.

It looks like a Māori eel trap, a hīnaki​, stretched across the river. Or perhaps a resting taniwha.

Scratch that. It might have looked like a hīnaki or a resting taniwha, if someone had been allowed to build it. For now and probably forever, it exists only in the minds of its creators, in computer memory and on paper.

The bridge design was one of 13 submitted to a request for proposals in 2017 when Government rebuild agency Ōtākaro sought ideas for a new pedestrian and cycle bridge to cross the Avon River in Christchurch's north frame. Known colloquially as an art bridge, its official name was the North Frame Pedestrian Bridge (NFPB). After submissions came in, and all the work had been done, Ōtākaro scrapped the project without warning. Submitters received a form letter.

Until October 2018, few people knew what any of the submissions even looked like. Then an obscure UK journal called Structural Engineering International published an article about He kōrero takiwā, he takiwā kōrero, which means "stories within spaces, spaces defined by stories". That was the name of the bridge designed by two University of Canterbury fine arts PhD students and four engineering PhD students in an unusual collaboration.

It all started with a fortuitous meeting. Paul Millar, head of humanities and creative arts at the university, bumped into Alessandro Palermo, a professor of structural engineering and materials. Palermo is a big fan of bridges. "What if Christchurch became a city of bridges?" was the name of a talk Palermo gave at the university. Coming from Italy, he knew the tourist appeal of attractive footbridges.

Millar heard that Ōtākaro and the Christchurch City Council were looking for proposals for an artist-led bridge project as part of the Christchurch Central Recovery Plan (CCRP). Ōtākaro wanted it to "specifically reflect the fluid nature of the Avon River with its winding curves, the habitat and ecology of the river environment and the connections people have with the area" and expected it to be built by mid-2018.

Millar got Palermo together with Aaron Kreisler, who heads fine arts, and the three of them devised a plan and picked six bright kids to carry it out.

It was not necessarily easy. Who knew that sculpture students and engineering students think and talk in different ways? One of the roadblocks was over the word "organic".

Engineering students Ana Isabel Sarkis Fernandez​ and Royce Liu and arts students Emma Wallbanks and Donna Patterson come together a few weeks after the journal's publication, to reflect on the experience. The engineers gather on enemy territory – the arts building. We are five levels up. Outside it pours with rain.

The other two engineering students who participated are Gabriele Granello and Brandon McHaffie.

"We definitely have very different ways of approaching a problem," Sarkis Fernandez says. "Even the language we use to convey our ideas is very different."

Guido Medici The interior of the bridge relates to Māori metaphysical ideas about light and dark.

So, the "organic" problem. "We would use the word 'organic' as a formal reference," Wallbanks says. But the engineers scratched their heads. For them, organic would literally mean something growing, something alive.

"In the beginning we were struggling and it seemed impossible," Sarkis Fernandez says. "A few of us even thought about quitting."

"You did start to question what you had got yourselves in for," Wallbanks adds. "But I didn't want to abandon it fully."

The professors stepped in to smooth things over. Within weeks, a concept was created.

Sarkis Fernandez has one of the original sketches of a hīnaki, which looks like a woven tube used to catch eels and fish. You can see it was a challenge to turn that sketch into a working bridge.

Why an eel trap? Because the Māori name for the Avon, which is also Ōtākaro, means the place of a game, as a reference to children who played games on the river banks while adults gathered food in the river. The river was a mahinga kai, or place for gathering food. So a large bridge across that river, built to resemble an eel trap, made sense.

It was designed to be built in Corten steel, or weathering steel, which develops a rusty appearance when exposed to the elements. This would help it look less industrial and more homemade. They considered more organic – that word again – materials but as the brief called for durable and low maintenance materials designed to last at least 50 years, steel was a better fit.

It was "conceived as both lure and trap," as Sarkis Fernandez, Liu and the other engineers put it in the journal article. From a distance, the bridge would lure passers-by. The head-like opening leads into a curved interior that would develop the sense of mystery, as "apprehension might arise in the user, the interior skeletal-like structure feeling somewhat like the darkened insides of a giant beast".

A window-like shape – they call it an "oculus" – would admit light to a seating area. This burst of light after dark had a metaphysical dimension: "These concepts relate to the Māori spiritual understanding of te pō, the night – the state of chaos, of nothingness – which leads to te aō, the light, emblematic of a spiritual transition or change."

It is a bridge with meaning, a sculpture that has a function. Another oculus occurs further along and then a "tail" forks into two possible exits.

Was it ambitious? The estimated cost was $5.92 million, but by making some changes, including reducing the span from 50 metres to 40m and dropping one of the two exits, they could save almost 30 per cent.

But that may not have been enough. A spokesman for Ōtākaro – the rebuild company, not the river – confirms the pedestrian bridge had a budget of just $3m to fund design, geotechnical work and construction.

So, what happened? In the letter that went to Kreisler, and presumably to representatives of the other 12 projects, Ōtākaro's general manager of development, Robert Fiske​, said the project was "on hold" while Ōtākaro and the council worked out what is being developed north of the river, around Kilmore and Peterborough streets.

University of Canterbury Structural Engineering and Materials professor Alessandro Palermo hopes the bridge collaboration will lead somewhere.

A year later, "on hold" has quietly turned into cancelled.

The Ōtākaro spokesman writes: "The recent completion of the North Frame section of the City Promenade has reinforced the need for a river crossing in the identified location to make it more usable for pedestrians and cyclists." However, "Council preference is for a functional, simple and low maintenance bridge. Accordingly we are progressing the design on that basis to enable construction to start next year.

"Unfortunately this means none of the submitted concepts will be progressed. We have advised those whose designs were shortlisted and we appreciate the efforts of all those who put forward proposals."

The "simpler bridge" is likely to have a lower budget than the original $3m.

Back at the university, are the students disappointed that their bridge will not go ahead and that a cheaper, plain alternative will be built instead?

Wallbanks says it was more disappointing that "we never had any feedback on our submission, which we were really proud of in the end. All of us were united on that."

They hoped there might be some public involvement, a public consultation process. But gossip filled in the vacuum.

"We heard through the grapevine that some had been edited out at the initial stages," Patterson says. "It was very dysfunctional. We heard things through the grapevine more than the official channels."

Who did the judging? On what basis? What did the other submissions look like? They have no idea.

"If there's a dozen other bids and we've all spent in excess of $10,000 to do this, then at least why don't we have a symposium of all the people involved, show what people came up with and talk about the process," says Paul Millar, who adds that the university "would host a symposium in a minute".

Ōtākaro says it would be up to the other submitters to identify themselves and come forward before that can happen.

Looking at the pictures, Millar says, "I feel quite disappointed that it is only ever going to exist as an imagined concept. It would unsettle the rebuild process a bit."

Through Palermo's international contacts, Sarkis Fernandez presented the design at a footbridge conference in Germany. That positive exposure led to the journal publication.

"It's interesting that it's had so much international recognition because it's so specific to Christchurch," Wallbanks says.

Might something good emerge from it? Perhaps. Palermo might get his city of bridges after all.

In an email, he notes that he is discussing the possibility of a new university course called "Beyond aesthetics of bridges", which would bring art, history, narrative and environmental contexts into the process and nurture the next generation of engineers and bridge artists.

"In a way 'the bridge to nowhere' is leading to something," Palermo says. "I hope that New Zealand will become the country of artistic bridges all integrated or embedded in its beautiful sceneries."