The report, Rail Up! The Benefits of Elevated Rail, is a project by design students at RMIT University and the University of Melbourne and follows research published earlier this year by the same schools, which concluded that rail bridges produced better results than other methods, including rail trenches.

The new report argues that the Frankston and Upfield rail lines are the most ripe for elevation – dubbed sky rail – of all lines in Melbourne, because they have many level crossings bunched a short distance apart, making it technically difficult to remove them individually.

Jewell station as it looks now and what it might look like. Image: Nicola Inskip/Melbourne School of Design

The Andrews government has plans to remove eight more level crossings on the Frankston line by 2022 and, in response to vocal community opposition, has already ruled out an extended "sky rail" solution.

Bayside residents rally against elevated rail on the Frankston line. Photo: Jason South

Instead, it is tackling the eight sites one by one, and has confirmed rail bridge designs for three of them, at Station Street and Eel Race Road in Carrum and Skye/Overton Road in Frankston.

But the Melbourne School of Design report, led by RMIT's Ian Woodcock and John Stone from the University of Melbourne, encourages the government to stare down local opposition to elevated rail, arguing a piecemeal approach to level crossing removal could leave many of the problematic crossings in place indefinitely.

"On the Frankston line, the removal of additional crossings is prudent," it states. "Many are close together and the removal of some crossings in isolation will make it difficult to remove others in the future."

Design for a proposed rail bridge across Mordialloc Creek on the Frankston line. Image: Victor Eric Goh/Melbourne School of Design.

The report argues the fact the line is so close to Port Phillip Bay could create a serious problem in years ahead if it is trenched.

"Grade separations that require the road or rail to be submerged, as in the case of trench rail, would place the line beneath the water table with the consequent likelihood of flooding in the sunken portion," it says. "This risks damage to track, stations and trains along with enormous disruption to services with associated congestion impacts."

Proposal for new Mentone station with removal of Balcombe Road level crossing Image: Edward Grutzner/Melbourne School of Design

Three level crossings are also planned to be removed on the Upfield line as part of the government's promise to remove 50 crossings by 2022 –Moreland Road, Bell Street and Camp Road. No potential designs have been released.

The Rail Up! report argues 21 crossings could be eliminated on the line by building a single elevated track all the way from Royal Park to Upfield station in Campbellfield.

An extended linear park could be built below, creating extra green space in a part of Melbourne's north that has few parks and is experiencing rapid population growth, it argues.

An extended elevated railway would also provide train passengers with pleasant views of the city, compared with concrete trenches that dominate recent removals, including along the Frankston line between Bentleigh and Ormond.

The view from 12 metres above Chelsea railway station on the Frankston line. Image: Supplied

The view from the platform at Springvale station, recently dropped into a rail trench as part of the Springvale Road level crossing removal project. Image: Supplied

The government is building elevated rail along the Cranbourne-Pakenham corridor, Melbourne's busiest rail line, as it removes nine crossings between Caulfield and Dandenong. The project has proved controversial, with residents near the line fearful of diminished amenity and reduced property values.