A team of architects and engineers have designed an elegant arching structure to replace the troubled Auckland Harbour Bridge.
As Transit NZ pushes on with a study into a tunnel under the harbour for up to $3 billion, leading architectural firm Jasmax has produced a radical concept design spanning Waitemata Harbour between Wynyard Pt near the Tank Farm on the waterfront and Onewa Rd in Northcote.
It features a giant angled pylon supporting a splay of cables in the shape of a sail, reflecting what its designers say is Auckland's nautical history.
The concept, made available to the Herald yesterday in the wake of Transit's decision to ban trucks from the outside clip-on lanes of the existing harbour link to ease fatigue pressure, is based on structures in Spain and Mexico by the architect and engineer Santiago Calatrava.
It would carry cars, buses, bicycles, pedestrians and possibly even light rail carriages.
Although emphasising that the concept was "a toe in the water", Jasmax director Hamish Boyd said the Holmes Consulting Group of engineers had studied it and confirmed such a bridge could be built.
His firm had decided to develop a visual concept after being approached by Auckland City Council's transport committee chairman, Richard Simpson, who is pushing for the existing bridge to be demolished to free up prime coastal land in favour of a lower-gradient structure capable of carrying light-rail if needed.
Mr Simpson said an elegant new bridge, funded largely through land sales around St Marys Bay and Northcote, would be about one and a half times longer than the existing link but could attain the same height on a lower and more visually appealing gradient.
Although it could present challenges to redevelopment plans for the Western Reclamation, it would free up at least four times as much land and allow Westhaven to be restored as a popular beach.
Demolishing the existing bridge would be strongly resisted by Auckland City Mayor Dick Hubbard, who wants a tunnel as an additional link to end the region's dependence on "a single ribbon of steel".
But Mr Boyd derided the existing structure as a "bit of a bailey bridge" which he said had no place on the Waitemata and required motorists to take an otherwise unnecessary dog-leg around St Marys Bay to reach it.
Mr Simpson said the replacement would enhance rather than detract from the Waitemata's splendour and put Auckland on the world map.
"Let's have a piece of world-class architecture."
Auckland City transport committee member Richard Northey backed the design.
"I understand a tunnel that length would have operating costs of about eight times that of a bridge and there would be a real problem with gradient if used by trucks coming up from the harbour to the motorway," he said.
But Deputy Mayor Bruce Hucker favoured a tunnel provided it could be linked with the Wynyard Pt development due to unfold over the next 20 years.
Transit says it is not far away from seeking land designations for a possible tunnel, on an understanding it has been the strong preference of local councils.
Transport planning chief Wayne McDonald said the study should be complete within months, if not weeks, and would include a firmer cost estimate.
He emphasised the aim was to prepare for designations for the protection of land in the midst of redevelopment plans for the Western Reclamation, which remain under sensitive negotiations between the city council and Auckland Regional Holdings, owner of the port company.