RENOWNED Hunter rail historian Ed Tonks has raised concerns about the Fernleigh Track's tunnel, warning the heritage structure could be damaged by vegetation growing around the northern entrance. .
"I'm very concerned about the vegetative growth over the top and the sides," Mr Tonks said.
"If that overgrowth is not addressed, there could be safety issues, not to say anything of it as a heritage item.".
Ed Tonks, who was on the committee that helped transform the former rail line into the popular walking and cycling track, pointed out the growth above the northern portal of the tunnel, which was built in the late 1880s and 1890s.
"You have a look at the entrails of the plants, starting to come down, they're dribbling and drifting down closer to the track itself," he said. "They certainly could represent an issue, striking people in the face and the head and stuff like that, if it continues down further."
Ed Tonks noted ferns growing out of the bricks near the portal of the 181-metre-long tunnel.
"And as they grow, they're going to loosen the grip of that mortar on those bricks," Mr Tonks said, before he noticed cracks in the brick face.
"These cracks here look very, very extensive and they may well be caused by the adverse effects of the vegetation, the biotic weathering of the ferns."
The Fernleigh Track, from Adamstown to Belmont, is maintained by Lake Macquarie and Newcastle councils. The tunnel is in the City of Newcastle section.
The historian said he had contacted the council more than two years ago about the growth and was told an engineer would contact him to discuss the issue: "I haven't heard from that engineer."
Ed Tonks said before this section of the Fernleigh Track was opened in 2003, about $1 million was spent on the tunnel, ensuring it was structurally safe.
"That could come to nought, if some of that botanic weathering corrupts the tunnel entrance," he said.
A spokesperson for the City of Newcastle confirmed the council was responsible for vegetation control at the northern end of the tunnel.
"Scheduled maintenance to the area is carried out every six to eight weeks, with crews undertaking mowing, weeding, debris removal, pavement sweeping, and cutting back and clearing vegetation," the spokesperson said.
As for checking the structure and its safety, the spokesperson said City of Newcastle engineers monitored and routinely inspected the tunnel.
"The last routine and survey inspection was carried out on 19 February, 2021," the spokesperson said. "The results of the last inspections indicated there were no major structural defects with the tunnel."
The next inspection and survey was scheduled for February.
The spokesperson said the council had "scheduled to engage external structural engineers to complete additional investigations and assessments on the tunnel, which will assist in identifying if any further maintenance works are required".
The City of Newcastle spokesperson described the tunnel as "a treasured asset". Ed Tonks agreed it was a treasure and believed it deserved more care.
"The key element [of the track's heritage significance] is this tunnel," Mr Tonks said. "Without this tunnel, this railway line would not have operated for more than slightly more than 100 years."
Read the NewcastleHerald's week-long feature series, On The Fernleigh Track with Scott Bevan. Part one is here.