City rail loop vital - at street level

By GRAEME EASTE*

At first blush the Auckland City Council's announcement of plans for a rail tunnel from the new Britomart station to the western line near Mt Eden via the central city was exciting news.

On closer inspection, however, it appears more a cynical ploy designed to distract and defer action than a serious proposal. It is a rehash of an old idea that was finally rejected for very good reason several years ago.

Despite suggestions of endorsement by the council's transport committee, this plan has yet to be considered by any council committee. With no budget authorised, investigations have been fairly cursory.

Make no mistake, an inner-city rail loop is essential if we are to get full value out of the Britomart as the number of passengers grows. As configured, there are only a few years' grace before the station will be running at or near capacity.

To understand how the need for the loop is connected to the station's continuing viability, we need to consider how services will operate there.

When the underground station opens in July, it will function as a stub terminal. Every train that enters will have to reverse direction and leave from the eastern end via the same twin-track tunnel.

This configuration will limit service frequency because trains will cross paths in negotiating the switching network between the lower portal of the tunnel and the platforms. Depending on operating protocols, the safe limit will be 18 to 22 trains (36 to 44 movements) an hour.

The initial level of service will run a train every 10 minutes in both directions on each of the three corridors (central, southern and western) leading to Britomart. Theoretically, this means 18 trains an hour entering, then leaving, Britomart.

It will take at least three years before this is achieved because 10-minute headways will not be safe on the western line until it is double-tracked, though the existing 30-minute headway could be reduced in stages as key sections of track are duplicated.

Once all lines are running at 10-minute headways, Britomart will have only a few spare movement "slots" that will cater for long-distance services and a handful of supplementary services at peak times.

With services running three times as often, rail will become a much more attractive travel option. Other improvements will enhance this. Rolling stock and suburban stations are also being substantially upgraded. Despite many delays, integrated ticketing and better co-ordination with bus and ferry services are in the pipeline.

With passenger numbers certain to rise dramatically over the next few years, how is continuing growth to be catered for?

It is not feasible to significantly increase the capacity of each train because the platforms at Britomart and the 40 suburban stations are being designed for six-car train sets (110m long). Extending them all would be difficult and expensive, so to increase capacity it will be necessary to run more trains.

But to run more trains through Britomart we have to begin operating it less as a terminus and more as a through station, reducing conflict in the switchyard. This is where the loop comes in.

Although an underground loop has been dreamed about for decades, the concept was sidelined several years ago. In 2000 a design programme was organised to work out how Britomart could best be connected to the central city and the wider rail network.

A key result was acceptance that modern light-rail systems work best at street level. It was also realised that the traditional western route would bypass large numbers of potential passengers best served by locating stations in Queen St, Wellesley St close to the universities, and at the super-hospital in Grafton.

In 2000 and 2001 workshops were conducted to fine-tune the route and details such as streetscape design. The agreed route ran up Queen St from the Britomart, turning up Wellesley St between the universities, then across Grafton Gully to Auckland Hospital by one of several possible routes, and connected with the western line at Khyber Pass.

The total cost, including some major streetscape work in Queen St, was estimated to be $120 million to $130 million, less than a third of the underground proposal.

Design work for this central transport corridor and Britomart was conducted in tandem. Integrated into the winning Britomart design were twin connections for light rail ramping up to and through the ground floor of the old Chief Post Office building. Although not yet built, provision for the ramps exists behind the walls of Britomart, and the ground floor of the CPO has been lowered 2m to cater for street-level connections.

Design work continued under the present council until last December when it was resolved to "not continue work on securing a street-based light-rail corridor through the central area at this stage".

What a pity, because all the preliminary design work is in place. If necessary, the Auckland City Council could fund it immediately from two major windfall cheques received lately, neither of which was even dreamed of a year ago.

Before selling some of its Auckland Airport shares, the council received $54 million from a capital restructuring of the airport company. Add in $82 million for the council houses and there is $136 million available. In practice, this project should be eligible for at least 50 per cent funding from Infrastructure Auckland and Transfund.

However it is funded, it is important that progress is made on a rail loop connecting Britomart with the inner city and the western line.

It would be a pity if we were still debating the best option in five years, by which time we need it operating.

We now have two competing visions for the loop. Rather than pushing only one proposal, the council should conduct genuine consultation on this issue by putting both options out for public consideration.

* Graeme Easte, a member of the Western Bays community board, is a spokesman for the Campaign for Better Transport.

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