The Electrical Trades Union has warned employment at Ballarat's Alstom train facility is in danger of "falling off a cliff".
The company reiterated calls for a new government contract to maintain jobs at the plant once the current X'Trapolis 2.0 train design contract is complete, but the union says the state government has promised nothing new - which could leave the company's presence in Ballarat at risk.
About 75 to 80 workers in Ballarat design and assemble the new metropolitan trains, with the latest order, for five trains of six carriages each, on their way.
The state government has not yet committed to building the X'Trapolis 2.0 in Ballarat, with a decision to be made at a later date based on the outcomes of the design works.
A state government spokesperson said $103.5 million had been invested in the five new trains in the 2018-19 Budget, and the first train from the order is expected to be delivered in late 2019.
"The government has had a long productive working relationship with Alstom and we will continue to support local content and jobs in our pipeline of new and upgraded trains," they said in a statement.
"In October 2018 the government engaged Alstom to complete a preliminary design for a X'Trapolis 2.0 train with higher local content which secured Alstom's Ballarat manufacturing staff through to the start of work on the five new X'Trapolis trains."
ETU organiser Damian King said the new X'Trapolis 2.0 project had not been included in this year's budget.
"The state government's been asked to clarify its plans - do we have the go ahead or not - and there's been no answers in terms of that," he said. "Now it's July, and effectively, unless decisions are made now, you're falling off a cliff work-wise - it's a job that requires some planning."
FROM THE ARCHIVE: Iconic train manufacturer Alstom faces closure threat
Mr King said Alstom had tried to retain its workforce by assigning non-construction related jobs.
"(Premier) Daniel Andrews said there'd be a pipeline of manufacturing work, not stops and starts," he said.
"He needs to follow through - we're not going to have (engineers) cleaning floors."
More than $4 billion has been invested in the last four years to upgrade infrastructure and rolling stock in Victoria, including $500 million in 24 X'Trapolis six-carriage sets from Alstom.
The massive investment indicates why further work should go to local employees in Ballarat, Mr King said.
"We've had the most massive investment in rail infrastucture and rolling stock, so it's an absurdity," he said.
"There's no rational reason for this to happen, we've got this massive investment, and a successful manufacturer - it doesn't make sense from the state government perspective."
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