Marion City Council wants state regulations changed so that more trees can be planted in the median strips of major arterial roads in the council area.

Brighton Road, Sturt Road, Oaklands Road and Morphett Road have all been flagged by the council as sites which could do with more trees in median strips and along footpaths.

According to State Government figures, hitting a fixed object such as a tree or Stobie pole is the most common type of serious road crash in metropolitan South Australia, representing 27% of all such crashes.

However, Marion Mayor Dr Felicity-Ann Lewis said that a balance had to be struck between road safety and amenity.

“If you want people to actually use footpaths and use active transport [but] don’t have the amenity, people aren’t going to use them,” she said.

“I haven’t seen the data, but it doesn’t appear to me that streets with lots of trees seem to have any more car crashes or injuries.”

City manager of road safety for the RAA Charles Mountain said that for the sake of road safety, trees should only be planted in median strips if enough space is allowed for driver error.

“[Trees] should be placed outside of what’s called the clear zone so that if people have to divert from the travel lane, they’ve got some space where they can make a recovery before they hit the tree,” he said.

“If that can’t be achieved, then they might need to have some kind of protection or perhaps not be installed there in the first place.”

Mountain told InDaily he did not know of a major road in the Marion City Council with a median strip wide enough to be safe for new tree plantation.

“To be honest I can’t think of any off hand where they’ve got a median of sufficient width … comparable to the likes of Greenhill Road, where you’ve got probably around four metres from the edge of the median to the actual tree,” he said.

“If they’re installed in a wide median [and] if it’s a straight stretch of road where they’re unlikely to be negotiating bends and things then it’s probably going to be relatively safe.”

Marion City Council won a vote at the Local Government Association’s general meeting last week to have the association lobby for a change to the Department of Transport’s ‘Operational Instruction 19.8’, which discourages tree planting in median strips.

“DPTI’s document focuses on road safety on the arterial roads and is generally not in favour of planting trees that can become a significant road hazard to all road users,” a department spokesperson said.

Lewis said the motion had been proposed after the City of Holdfast Bay contacted Marion City Council to complain that the department was unreceptive to the planting of more trees.

“They were sort of saying to us, ‘can you do something’,” she said.

“We thought, well, there’s no point in us writing again to the department, we’ll just get the same letter, so why don’t we take it to the general council meeting and see if other councils feel the same.”

Marion City Council’s notice of motion to the LGA acknowledges that almost all trees have trunks which will eventually grow wide enough to catastrophically stop a car.

But the document argues that it would be less harmful for a car to crash into a tree than into an oncoming vehicle.

LGA Acting President Lorainne Rosenberg said the association had not yet contacted the department and that a report would be provided on the subject for the next general meeting of the LGA in October.

“The appropriate LGA officer will consider whether further research is required, or if there are any matters which may need to be addressed by the LGA Board, before we seek to engage with the Department for Transport and Infrastructure,” she said.