Southern suburbs rail commuters are far from happy with plans to reduce the capacity of the car park at Thornlie train station.

Transport minister Rita Saffioti declared up to 50 car bays, equating to 11 per cent of the car park, would be removed to allow for work to be done on the new Thornlie to Cockburn link.

A 1000 bay car park will be built approximately three kilometres away at the proposed Nicholson Road train station as part of the project.

Thornlie resident Sarah Read said the maintenance would have a significant negative impact on commuters.

“My kids and I catch the train every day, cars are always packed in as it is, this is going to make it even worse,” she said.

“It’s all well and good to have a new car park, but it’s three kilometres away, some people won’t be able to get to Nicholson Road.”

Construction for the Thornlie to Cockburn link started in August, with Perth’s first east-west rail connection serving the growing areas between the Armadale and Mandurah train lines.

Thornlie MP Chris Tallentire said the link will significantly improve transportation in Perth.

“It will make a huge difference… commuters will be able to travel across the city rather than having to stop and transfer in the busy CBD,” he said.

“In regards to concern about the car park maintenance, we think there will be quite a large shift of people from the Thornlie train station to Nicholson Road so they will be fine in that regard … however we are certainly keeping an eye on any possible complications.”

Sarah Read said while she acknowledges how important the Thornlie to Cockburn link will be, the side effects are concerning.

“In my opinion it’s poor planning, the inconvenience this is going to cause will be massive… how is it fair for Thornlie residents to have our access limited?” she said.

Construction for the Thornlie to Cockburn link is projected to be completed by 2021.

As a photo gallery below shows, parking at Thornlie is already at a premium.