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Careful planning will allow the Auckland rail network to be electrified without major disruption, passenger operator Veolia Transport believes.
Managing director Chris White said that the high level of disruption suffered in March by western line passengers, from signal faults caused by track duplication, need not be repeated during a $1 billion-plus electrification project due to start over summer.
He said the duplication project was building greater resilience into the system, which would give train controllers more operating leeway during the closure of short lengths of track for underground cables to be laid or for overhead power lines to be erected.
"I am not saying there will be no disruption in future, but we hope to get by without a repeat of significant problems," he said.
It was no surprise that after many years of operating a shrunken network, the railway industry had run into difficulties on its first substantial growth project since the main trunk line was electrified in the 1980s between Palmerston North and Hamilton.
"There is a level of expertise that has to be built back and, to some extent, some of the trouble on the western line was a reflection of getting used to a big project."
But despite Mr White's confidence that lessons had been well learnt from the duplication problems, electrification would require a high degree of co-ordination among several parties on train purchases and infrastructure development.
Although the main responsibility for providing the necessary infrastructure will rest with Government rail agency Ontrack, Mr White said his company was involved in several big overseas electrification construction projects - in Mumbai, Seoul and Jerusalem - and was ready to provide expertise if called upon.
The company also runs electric rail services in Stockholm, Dublin, Melbourne and Bordeaux.
Mr White said electrifying a level railway track was relatively straightforward, but modifying structures such as bridges to accommodate overhead power lines was challenging.
Ontrack has yet to list modifications needed to electrify Auckland's rail network from Britomart to Papakura and to Swanson, but spokesman Kevin Ramshaw said the 350m tunnel between Parnell and Newmarket was already large enough to take power lines.
That is not the case with the 450m tunnel between Swanson and Waitakere, which the Auckland Regional Transport Authority has told the Government would be too costly to modify.
Swanson will, therefore, be the northwestern extremity of the electrification and the track duplication projects.
Mr White said diesel trains could still run on electrified lines, but it had yet to be determined where passengers heading for Waitakere would have to transfer between services.
The Auckland system, which the transport authority expects will use about the same amount of electricity as a year's growth in the region's power demand, would gain a high level of operational security by having its own substation.
Mr Ramshaw said the 25,000-volt, alternating-current supply system proposed would be more reliable than Wellington's 1500-volt, direct-current system, which was more than 50 years old and needed considerable physical supporting structures.
The Auckland transport authority has proposed a system using lighter steel or concrete masts and cantilever brackets, and smaller-diameter overhead wires.
A ground-level power supply has been ruled out as too dangerous, especially given a lack of security fences along much of Auckland's rail network.
* Ontrack is holding open days this afternoon and on Saturday with the transport authority and Waitakere City Council to discuss plans and construction impacts of a 1km trench to be dug up to 8m deep through New Lynn for duplicated railway tracks.
The Government has pledged $120 million for the project, and Waitakere City intends providing $55 million in cash and property.
The sessions will be held at the New Lynn Community Centre in Totara Ave from noon to 6.30pm today and from 10am to 3pm tomorrow.
* Waitakere City schools are being sent posters and stickers urging children and their parents to take extra care around railway lines and crossings once a 7.2km section of duplicated track between New Lynn and Henderson opens on June 5.
