Plans to link Manchester's Metrolink network with Rossendale have been heavily criticised by the chairman of the East Lancs Railway (ELR).
Proposals for a tram-train connection between the two areas - passing through Bury - would see old London Underground trains travelling along the historic ELR line to avoid having to construct new tracks.
But those who keep the heritage railway line running say the scheme could spell the end for their services.
READ MORE: Rossendale could get Manchester Metrolink connection with train-tram link on old ELR line
Chairman of the East Lancashire Railway, Mike Kelly, said the latest business case for the project, currently being worked up by Rossendale council, would require 'enormous capital investment'.
He pointed to four previous similar studies which had concluded that using the ELR tracks would not be a viable solution.
The council hopes a link between Rossendale and Manchester would improve travel for the 9,000 residents of the valley who travel into the city to work each day.
If successful, the current plans would connect these people to the Metrolink system in Bury via light-rail trains travelling through Rawtenstall and Ramsbottom, with three new stations at Ewood Bridge, Stubbins and Buckley Wells.
However, Mr Kelly has pushed back against the proposals.
“While we understand the desire for greater connectivity between Rossendale and Manchester, imposing a commuter service to run on the heritage railway is not the way to go about it," he said.
"This will be the fourth such study in nine years, many of which have concluded this proposed commuter line isn’t economically viable and would require enormous capital investment and annual subsidies.
"The development would, at best, threaten the efficient and effective operations of, and at worst force the complete closure of, the heritage railway line operated by East Lancashire Railway, thus threatening the growth plans in Bury town centre, Ramsbottom and for Rochdale at Heywood and Castleton.
"ELR is a leading tourist attraction in the region, hosts important educational visits, creates jobs, and contributes £8m annually into local economies.
"The award-winning railway, rescued from dereliction by volunteers, is a unique ‘living history’ experience that hundreds of thousands of visitors attend every year and if remodelled in the modern form, those important heritage features will be lost forever.
"It is our considered view that a new commuter line cannot coexist with the existing East Lancashire heritage line that our volunteers have given so much time and effort to preserve over the last 30 plus years.
"This new study should look instead at alternative, more cost effective, deliverable options to improve transport links between Manchester and Rossendale."
Rossendale council has been handed £150,000 by the government to work up a business case justifying the current plans.
Leader Coun Alyson Barnes welcomed the funding and said new train-tram links would boost the area's economy. But she also emphasised much work was still to be done.
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