Passengers have once again been forced to stand or sit on the floor for most of a train trip from Melbourne to Warrnambool.
Shaunie O'Connor Hollerhead said the carriages were overcrowded on Sunday and it was difficult to access the toilets due to the number of people standing in the walkways.
"There's no doubt it would be unsafe if there was an accident due to how many people there were," Ms Hollerhead said.
She said she would be reluctant to use the service again in the near future.
Member for South West Coast Roma Britnell said it was the second time passengers had been left without a seat on consecutive Sundays.
She said it wasn't good enough that people were forced to stand or sit on the floor for most of the journey.
Ms Britnell said the train once again only had three carriages, which was insufficient - particularly at the end of the school holidays.
"Last week V/Line said it was an unexpected carriage fault that caused the shortfall on the service," Ms Britnell said.
"If it's the same thing again this week there needs to be some serious questions asked about the capability of the rolling stock being used on the Warrnambool Line and V/Line's ability to plan ahead."
Ms Britnell said Glenelg Shire mayor Anita Rank was on the train and said country passengers were being treated like second-class citizens.
"Last week the CEO of V/Line said the trains being used on the Warrnambool line would be in service until at least 2025," Ms Britnell said.
"If we are seeing these sorts of continual breakdowns now, imagine what type of delays we will be dealing with over the next five years as the carriages get older."
Ms Britnell said Daniel Andrews said upgrades to the line would begin in 2018 and be completed 12 to 18 months later.
"That work still hasn't started and documents leaked to the Liberal Nationals earlier this year showed the government had taken the cheap option and won't upgrade the line to allow for V/Locity's past Geelong," she said.
"The government has over promised on its Warrnambool line upgrade and it's passengers who are left to deal with the lack of action."
V/Line chief executive officer James Pinder apologised to passengers on the service which ran at reduced capacity.
He said two of the five carriages assigned to the service were removed last week for maintenance works.
"We're taking a number of steps to avoid a repeat of the experience our passengers experienced on the Warrnambool line over the past two Sundays."
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