“Transport[for NSW] will make sure there are replacement services,so there will always be a public transport service for everyone who needs it,” he said. “We need to get this work done so we can stay on track to build the Sydenham to Bankstown upgrade.”

He said Sydney Metro lost 22 opportunities to get the vital work done earlier “because the former Liberal government declared war on its own transport workforce”.

Along-running industrial dispute between the previous government and rail workers resulted in the cancellation of 22 planned shutdowns of the Bankstown line to allow construction work to be undertaken between November 2021 and December last year.

Sydney Metro said the series of school holiday and weekend shutdowns were necessary to complete major track upgrades and overhead wiring works before the final shutdown could start next year.

“This complex work requires power isolations. Sydney Metro contractors lost 22 rail possessions over a 12-month period due to protected industrial action last year and this work must be completed before the conversion,” the agency said.

The final year-long shutdown of the Bankstown line is needed to allow contractors to carry out work such as installing screen doors on platforms,testing driverless trains and commissioning the line. While it is shorter than a worst-case scenario of a 15-month closure,it is longer than the original forecasts of up to six months.

The shutdown will require officials to use about 100 buses to provide alternative transport to disrupted commuters,which comes at a time when NSW experiences anacute shortage of bus drivers.

The Bankstown line conversion is a part of theMetro City and Southwest project,which extends from Chatswood,under Sydney Harbour and the CBD to Sydenham and onto Bankstown.

The extra cost of converting the Bankstown line has pushed up the bill for Metro City and Southwest to about $21.6 billion,almost twice the original forecast of $12 billion last decade.

The main section of the Metro City and Southwest line from Chatswood to Sydenham via the CBD is due to open to passengers between April and June next year. The troubled section between Sydenham and Bankstown is expected to follow suit by October 2025.

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