Shorter platforms on the final section of Sydney’s $30 billion M1 metro line will restrict the operator to providing more frequent services rather than longer trains as passenger demand grows.
Despite the costly and disruptive project to convert the old T3 heavy rail line, platforms at five refurbished stations along the metro line’s 13-kilometre stretch between Sydenham and Bankstown would need to be extended to fit longer eight-carriage trains, which span 176 metres.
The six-carriage trains running on the existing M1 line, and which will carry passengers along the final stage when it finally opens, are about 132 metres long.
The shortest platforms at stations on the south-west section are 163 metres at Bankstown station, 168 metres at Wiley Park and Marrickville and 169 metres at Belmore and Lakemba.
The final stage is set to miss Sydney Metro’s internal target date of “mid-October” for its opening. The first service hinges on approval by the national rail regulator, which will then allow the government to reveal a date.
Any proposal to lengthen the platforms after it opens would be more disruptive, costly and take longer than buying extra trains to increase frequency to a service every three minutes during the peak, from every four minutes at present.
Sydney Metro customer and operations head Hugh Lawson said the agency would probably first recommend, if required, increased frequency, which would involve buying more trains of the same length as the existing six-carriage sets.
“Frequency is the easier and quicker pathway to provide more capacity, and also we know from our customers that frequency is something they really value,” he said. “The same trains more often is better than a longer train, but with a bigger gap between services.”
Lawson, who was project director for the M1 line’s city and south-west sections for six years, said longer eight-carriage trains would involve significantly more work to extend platforms at stations along the south-west corridor.
While some stations could be more easily extended, others would require train tracks to be moved before constructing platform extensions.
“It’s certainly quite an involved piece of work to go to longer trains. It’s much more straightforward to implement more trains because all the infrastructure is already configured for trains of that length. It’s just about running them more frequently,” Lawson said.
“If you wanted to go to longer trains in the future, then there would be work needed, and it varies from platform to platform and station to station.”
Apart from lengthening platforms at stations in the south-west, Lawson said glass panels at underground stations on the M1’s city-section between Chatswood and Sydenham could have to be replaced with screen doors while a major change to the signalling system would be needed to accommodate eight-carriage trains.
“They obviously are heavier [and] brake differently. They need to stop in slightly different locations, dependent on whether the extended bit of the platform is at the front or back of the train,” he said.
“It’s all achievable, but it’s certainly quite an involved piece of work to go to longer trains.”
In 2018, the then Coalition government decided to retain existing curved platforms on the line for the metro conversion. Straightening them would have required some stations, tracks, bridges and roads to be shifted, and would have proven costly.
When the south-west section opens, trains will be able to carry about 18,000 passengers an hour in each direction between Bankstown and Sydenham during peak periods.
An increased frequency to a train every three minutes would provide capacity for about 23,000 passengers an hour in each direction. In contrast, the T3 heavy rail line carried about 12,000 people an hour before it was permanently closed in 2024 to be converted to metro train standards.
Asked in September whether the purchase of extra trains was under serious consideration, Transport Minister John Graham said the government was thinking about “long-term decisions including new rolling stock”, but it would depend on patronage once the south-west section was bedded in.
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