It comes as the Victorian Government looks set to scrap the option for a dedicated tunnel from the airport into Southern Cross in favour of having airport trains use existing tracks between Sunshine and the central business district.
The News reported last month fast rail would be "as good as impossible" if the tunnel was ditched, as trains from Shepparton would compete with airport trains into the future.
Rail experts said this would quash the possibility of 200 km/h rail from Shepparton and would limit the speed of trains and the number of services in the coming decades.
Victorian Nationals leader and Member for Murray Plains Peter Walsh said linking Melbourne airport and the city using existing tracks would create congestion and long delays, and called on Prime Minister Scott Morrison to put the pressure on Andrews government to deliver the tunnel.
“If that dedicated line is not put in place, it will condemn regional Victoria, including Shepparton, to mediocre train services into the future,” he said.
“Using existing lines will put more trains on lines that are already near capacity.”
Victorian deputy Nationals leader and Member for Euroa Steph Ryan said if the tunnel is ditched, Shepparton will remain in the “slow lane” for decades.
“This is a decision that’s going to have ramifications over a century,” she said.“It will make our existing rail services even worse.”
Committee for Greater Shepparton chef executive Sam Birrell said the rail link was important for the future of Shepparton, as professionals wanting to move to the region often overlook the town in favour of regional centres with better train services.
“We’ve got a diversifying economy and we need professional people to move here,” he said.
“We need public transport links from Shepparton to Melbourne to ensure we get those professional people to move here, that’s what I hear from them all the time.”
State Member for Shepparton Suzanna Sheed said it would be disappointing if the tunnel was scrapped, but was first focused on ensuring the Shepparton rail upgrade was delivered with nine daily return services between Melbourne and Shepparton.
The rail upgrade has been allocated $356 million and is in stage two of works, expected to be completed in 2022.
A business case for stage three, which will see trains travel up to 130 km/h and nine return services from Shepparton, has started.
Federal Member for Nicholls Damian Drum also called for commitment to the tunnel and said it was the only way to get fast rail to Shepparton.
A state Department of Transport spokesperson said they were working closely with the Federal Government on all options for airport rail, but did not indicate when they would provide more detail on the project.
A federal Department of Transport spokesperson said they were working with the Victorian Government on the design of the airport rail link, but also gave no further detail.
The federal and state governments have each committed $5 billion to the airport rail link.
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