Overhead rail track 'better than tunnels'

Greenways Project claims its 'wow factor' alternative would save $700m

Supporters of a central Auckland rail loop are suggesting an overhead rail track as a cheaper alternative to a 3.5km pair of tunnels costing almost $3 billion.

Engineers and architects of the voluntary Greenways Project believe an attractive high-tech link could be built above city streets and the motorway junction for $700 million less than an estimate of $2.4 billion for underground rail.

That estimate is calculated to top $3 billion in inflation-adjusted terms by a target completion date of 2020, before being trimmed to $2.86 billion by selling surplus land yet to be bought along a tunnel route to Mt Eden.

Greenways has put the cost of its alternative at $1.68 billion to staff of Auckland Mayor Len Brown, and say it should be seriously considered before the council approves a 10-year funding plan next month.

Its suggestion would entail a wider loop than the tunnels, carrying trains above Fanshawe St from Britomart and skirting around Victoria Park to head south. Trains would then run above the motorway - but under the Karangahape Rd bridge - to a junction at Mt Eden with the western line.

Although that would take them further from Queen St than the proposed tunnels, which would run below Albert St to Karangahape Rd and beyond, the group is suggesting a feeder tram circuit for an extra $50 million to maximise patronage.

The group, formed to promote walking and cycling routes through Auckland's green belts and utilities corridors, has offered Mr Brown the idea as a more affordable means to what it calls the same rapid transit goal.

But the mayor was yesterday sticking to tunnels, despite opposition from the Government and uncertainty about funding, saying his council often received proposals for alternative transport systems.

"We can't keep revisiting everything, or nothing would get done and more money would be wasted," he said.

"This project has been talked about for decades, it has been peer-reviewed by international experts, and now we're getting on with it."

But the project received only 30 per cent support among 655 public submissions on the 10-year plan.

Architect and Greenways spokesman Stephen Smythe said the group agreed with Mr Brown that a central rail loop was needed to open up Britomart and allow trains to circulate through the city. But it feared money would be too tight for tunnels, meaning that without something more affordable, Auckland risked being stuck with a dead-end railway.

Although Mr Brown says Britomart was designed to handle triple the existing number of trains when connected to an underground line, Greenways believes an overhead railway would give greater capacity because of safety constraints in tunnels.

Mr Smythe said cost blowouts for tunnels were much harder to contain than for above-ground projects, but suspected elevated rail was overlooked because of "the legacy of old stuff which can be noisy and so on".

"Overhead rail has really only come back into its own in the past decade - it's moved into a high-tech arena these days in places like Dubai and The Hague."

It provided a "wow factor" of travelling above ground and opportunities to enhance cities with exciting urban design.

Fellow architect Pete Bossley said the group was not trying to undermine the tunnel proposal, but was calling for an examination of the alternative.

"We're just saying here's another idea, and its got its problems just like the tunnel has its problems, but it also solves a few and has a whole lot of attractions that maybe a tunnel doesn't have and that should be given some serious consideration."