It seems that the clamour to jump on the Auckland metro passenger rail bandwagon continues to show no bounds. Mayors Banks and Brown are now saying they are signed up to fully developing the electrification and also include the provision of an underground Auckland CBD loop line.

They seem to overlook the enormous cost implications. Even electrifying the existing metro lines and providing new EMU trains has an initial costing of nearly $1.2 billion.

Then we must consider the additional costs to ratepayers of paying for a part of the operating costs, as well as depreciation on the cost of the new infrastructure.

When all this upgrading of the metro rail system occurs is an interesting point. Aucklanders were initially told the new electric trains would be in place by the 2011 Rugby World Cup.

That date has now been scrapped and the new date is 2013. That is four years from now, which seems glacial speed in delivering a system that has been in the planning for so long.

We now hear from the latest Auckland Land Transport Strategy that many years will pass before we see major improvements.

The draft document indicates it is expected that the CBD rail tunnel will be constructed within the period 2021-2031. The costs of this tunnel and the building of stations deep beneath the CBD is something that has not been addressed at this early stage.

Indicative figures for costs have been bandied around but there are no firm figures. It is clear that passenger trains must negotiate the one line out of the Britomart Station for many years yet. Britomart has the potential to become a bottleneck that could take 20 years to resolve, especially if the passenger numbers more than double in the next seven years.

Aucklanders should be starting to get very worried where all this work on metro rail is heading. A fully electrified metro rail system, which included a double-tracked city CBD loop, was always the pipedream of our forebears. It would complete the dreams of former Auckland Mayor Sir Dove-Myer Robinson.

However I am certain Robbie would have wanted to analyse the enormous costs involved and understand whether we were getting value for money before giving the green light.

The Northern Busway Project was a good case in point. The final costs were considerably greater (nearly double) than the initial early estimations.

In the 40 or so years since Sir Dove-Myer was in power, the make-up of the Auckland region has changed considerably. We have gone from being a monocentric region with one large central business district in downtown Auckland to our current polycentric structure. We have regional centres in Albany, Takapuna, Henderson and Manukau City, as well as a number of smaller but important centres.

A few decades ago the majority of employment was in the Auckland Central Business District. People now find their place of work is in the outer suburbs where they live, or they travel to other parts of the region.

In the case of North Shore City, in excess of 60 per cent of workers do not have to leave that city to find work. These days the majority of the Auckland region's workers never have to travel into the Auckland CBD.

There are really two important considerations that must be worked through before we fully commit to electrification and new EMU rolling stock. These are costs for the present and future ratepayers and functionality of the planned system.

Metro Rail is already a huge cost to the ratepayers of the Auckland region. In the next three years the operational subsidies provided by ratepayers will amount to $43.3 million. The remaining 60 per cent of this three-year operational cost, which amounts to $108.2 million, comes from petrol taxes and road user charges paid by Auckland's motorists.

Once the new rolling stock is purchased someone, and again it will probably be the ratepayers and motorists, will then have to pay for the depreciation of this equipment. This will amount to around $12 million a year. There are probably other unknown costs.

Even if the financial issues were not a problem, one would have to consider closely what return would be achieved through the fare box. Auckland is not a region that is teeming with people all wanting to head into the Auckland CBD by train. Unfortunately for public transport planners, the majority of Aucklanders will still wish to use their own cars.

In 2001 when the Auckland Regional Council convinced the mayors and councils of the region to support upgraded heavy rail, we were told that 25 million passengers would be using the metro rail network by 2015. We are still a long way off this figure. The Auckland Regional Transport Authority has now revised its target down to 17 million passenger trips by 2016.

This is still a huge increase when last year's annual figure was 7.9 million.

Buses operating in the region carry six times the number of passengers carried by our trains. Buses are a far more cost-effective means of providing transport services to all our communities.

We could improve our bus services and entice far more people on to public transport for a fraction of the costs of this rail upgrade.

Aucklanders need to question and scrutinise the rail project before we commit ourselves to huge ongoing annual costs.

* George Wood was Mayor of North Shore City (1998-2007) and chairman of the Auckland Mayoral Forum (2001-2003)