An intrusion detection system along the corridor is targeted mostly at keeping people out.

In a historic moment for the final stage of the M1 line,a train carried passengers,including politicians,from Bankstown to Marrickville at up to 100km/h on Tuesday.

The project enters a crucial stage over the Easter long weekend when the existing stretch of metro line between Tallawong and Sydenham is shut from Friday to Monday.

The four-day closure will help integrate the south-west section into the M1,and allow critical testing of trains along the entire line from the city’s south-west to the north-west via the CBD.

Transport Minister John Graham acknowledged that the project had been disruptive for residents and businesses,but he said the metro line through the south-west would be a “game changer”.

He declined to say whether the final section would open in the third or fourth quarter of this year,but said the government would give commuters as much notice as it could about regular passenger services starting.

With high fuel prices making more peopleconsider public transport,the opening cannot come soon enough for those who have been forced to catch pink replacement buses since the heavy T3 rail line between Sydenham and Bankstown was shut in September 2024.

Regular commuter Van Phan is one of those eagerly awaiting the opening of the south-west section of the metro rail line.

“Ever since the line closed down I’ve had to rely on the pink bus,and that honestly is not very reliable. You can’t really plan around it,” he said. “It has extended my travelling time to work by 15 to 20 minutes.”

Testing is under way for up to 22 hours a day on the south-west section,and involves ensuring trains,signalling,platform screen doors and station systems integrate to deliver safe services from day one. So far,more than half of a required 30,000 testing kilometres have been completed.

The final stage between Sydenham and Bankstown was to be opened in late 2025 after a12-month shutdown of the old heavy rail line,but was laterdelayed until the second half of this year.

Under the original plans of the previous Coalition government,the south-west section was meant to open in 2024 at the same time as the rest of the second stage between Chatswood and Sydenham.

The installation of gap fillers to platforms at eight stations has added complexity to the operation of driverless trains. The small hydraulic platforms extend to the metro carriages before screen doors open,ensuring commuters can safely step on and off when the line opens.

Metro Southwest project director Alia Karaman said each of the 10 stations along the south-west stretch were at different stages,but construction on all would be completed by the end of May.

The cost of completing the final 13-kilometre stretch has blown out the cost of what was formerly known as the Metro City and Southwest project to as much $23 billion,from a previous forecast of$21.6 billion.

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