Thousands of Perth commuters will have their travel plans disrupted for about 18 months as the Armadale rail line is shut down for an upgrade and extension.
The 129-year-old train line to Perth's south-east will be transformed as part of the government's Metronet project.
There are about 20,000 boardings on the service every weekday.
About $2 billion of state and federal money will pay for the work, which includes elevating the rail line through Victoria Park and Cannington.
New stations will be built at Byford, Armadale, Carlisle, Oats Street, Queens Park and Cannington, while 12 level crossings are set to be removed.
The line will also be extended 8 kilometres to Byford.
Transport Minister Rita Saffioti apologised for the inconvenience but said a full shutdown was the preferred option.
"In making this decision, there were a number of options assessed, but it was clear that with this decision, the level of disruption is for a shorter period of time and is safer," she said.
"We want to inform the community about this shutdown as early as possible, so people could start thinking about the closure and their potential transport options."
Ms Saffioti said the government was looking at whether the line could continue to operate between the Perth city station and Victoria Park.
Commuter feedback sought
Transperth will survey Armadale-line passengers to assess what replacement services are needed during the shutdown.
Ms Saffioti said local communities would also be consulted.
"We understand we need to make sure we get services for children to access schools … and to make sure we can provide services to people to go into the CBD and other parts of the metropolitan area," she said.
"We saw with the replacement services when we shut down the Mandurah rail line that the replacement bus services did work well for that time.
"We'll be doing what we can to make sure we limit that impact and looking if there's anything else we can do in getting bus priority lanes [and] looking at some more temporary new bus stops in the city."
The work is also expected to affect the Australind Train Service so those passengers will also be surveyed.
When the project is complete, the regional train service will receive new locally-made railcars.
'It's a bit of a hassle': commuter
The ABC spoke to people who use the Armadale train line, with many concerned about the length of the closure.
"That is a hell of a long time for us because we live in Cannington, and we ride along that line so that would be really difficult," Kelly Deeble said.
"I have to be in town every day so I'm going to have to bus it but it's still a bit of a hassle.
"There has to be extra bus services because where we are, they come every half an hour and there's a lot of people near us."
Jamal Ahmed agreed on the need for extra buses.
"It means I'll have to look for other alternatives to get to work and get back home," he said.
"The train is very convenient for me, it's very cheap and it's very fast – it takes me about 15 minutes to get to work so if I catch the bus or drive, it's not going to be the best option.
"I think the best option is having extra buses but then you'll have heaps of traffic and heaps of people driving to the city."
