Brian Rudman: Tunnels for power lines make more sense than ugly pylons

By now Transpower must surely be getting the message that no one supports its 19th century plan to replace the 220kV electricity cables draped across South Auckland to Otahuhu with even bigger and uglier 400kV power lines.

Yesterday the Electricity Commission gave its broadest hint yet that in July it will give the proposed new wirescape a final thumbs down.

Commission chair Roy Hemmingway said that "based on a wide range of advice and the analysis undertaken to date, there are alternatives that provide the same level of electricity security but are less expensive than the proposed 400kV line. Therefore, at this stage the commission cannot approve the proposal."

He said it had already approved several transmission upgrades that would deliver improved security of power supply into Auckland in the short and medium term. This would, he said, put off until at least the middle of the next decade the need for a major new transmission line for Auckland and Northland.

No doubt to the disappointment of those living underneath, there was no indication that the social effects of the new pylons might have contributed to the commission's interim decision ... although Mr Hemmingway did signal that the commission was "interested in people's views on the desirability and practicality of acquiring a transmission corridor in advance of the need for a new transmission line".

Being an optimist, I'm presuming he's including the possibility of a tunnel as an alternative to stringing cables over South Auckland roof tops.

At least the commission's interim solution will provide the breathing space in which a commonsense decision can be made as to how best to provide for Auckland's power needs.

Last year Transpower's announced proposals were accompanied by threats that without a quick decision Auckland risked power cuts by 2010. Local lines company Vector increased the fear factor by warning that outages could occur by summer 2007.

Leading the opposition is the lobby group Underground in Manukau, which is driven by those most affected by Transpower's proposed new lines.

But that doesn't make their arguments any less justified. Indeed, back in August 2004, Murray Jackson, chief executive of electricity producer Genesis Energy, expressed incredulity at the existing distribution set-up.

"Opportunities exist to underground high-voltage conductors in Auckland to avoid limitations brought about by existing right-of-way access across roof tops."

He said "how town planners could accept right of way and not insist on easements is beyond imagination, making it near impossible to upgrade voltage on existing tower structures".

He was referring to the vast South Auckland housing estates where high-voltage cables drape across household roofs, so low they appear to play footsie with household television aerials.

Mr Jackson said "an underground tunnel from the Bombay Hills to Penrose is an investment that will satisfy Auckland's environmental and residential development requirements over the next 50 years. Such a scheme may initially appear too expensive, but the alternative does not work."

In a subsequent interview with Metro magazine, Mr Jackson came up with a "back of the envelope" estimate of $250 million for a 25km tunnel to underground high-voltage electricity from the south into Auckland.

Dr Rowena Poole, the deputy chair of Underground in Manukau, says such a tunnel would be the ideal solution. "If it's economical for Meridian Energy to build a 34km long tunnel to carry water to a new power station proposed for the Waitaki River, it must also be economical to build a tunnel to ship electricity into Auckland." A fair point.

Unfortunately for affected residents, the commission's alternatives to the new 440kV overhead cables includes pumping 50 per cent more power through existing lines. Dr Poole says that for people living underneath these lines, this is "profoundly disturbing".

The health effects of power cables is a topic of much debate. But as Mr Jackson said, that town planners allow high-powered electricity cables and family homes to co-exist in humming proximity "is beyond imagination".

For both health and aesthetic reasons, it's time to enter the 21st century. Transpower, start tunnelling.