In the past two months, bushfires have encroached on Australian cities, including Sydney, Melbourne and Canberra.
As people move out to the edges of these cities, sensible urban planning is urgently needed to mitigate future risk, says University of Melbourne professor Dr Alan March.
Australia is facing a complex set of challenges at the moment, Dr March tells Lynn Freeman.
In the past, politics has gotten in the way of sensible urban planning, he says.
“Most of the risks that we face, and the problems that we've had in this fire season, are the result of previous decisions that are very hard to reverse.”
After the 2009 Victorian bushfire, regulations were changed but much of the existing built environment remained vulnerable to bushfire, Dr March says.
“Those changes were fairly significant ... and had repercussions around Australia. But because of the way our planning system works, we don't go back and change existing settlements, it's very difficult to do.
“So we have a legacy risk, I would call it, in the nature of settlements that have been designed and built prior to a high standard of regulation being imposed.”
Particularly vulnerable are the edges of settlements, he says.
“We need to look more carefully at the really high-risk edge areas or interface areas of existing settlements. And perhaps say that's a location where we need to actively intervene and modify the interface between the urban edge and forest and other vegetated areas.”
In Australia, these urban perimeters are huge, Dr March says.
“For some of them, it's somewhat challenging to say where the edge is because we've had quite a lot of urban sprawl.
“We're talking thousands and thousands of kilometres around a lot of settlements that would need active and probably quite expensive modifications to them.”
Political pushback to proposed planning changes has also hampered progress, he says.
“One thing in Australia that rules supreme tends to be property rights. And it's a very strong government that modifies property rights to any great extent.
“We have seen in previous seasons, say after the 2009 bushfires, where the planning and building provisions were made much more risk-averse, and there was a very strong political pushback against that, which led some of those measures being reeled back in to make it easier and cheaper for people to build in high-risk areas.”
As climate change tightens its grip, areas that previously considered low-risk have become fire-prone, Dr March says.
“There are areas, particularly north of New South Wales and into Queensland, that have never burnt before, and certainly have not burned with any of the ferocity that we've seen. That means that some of our calculations are not as accurate as perhaps we thought.
“And because of that, it might mean that we need to go back and revisit some of those fundamental assumptions about the way we need to impose new regulations.”
Urban planning needs to encompass and intertwine many factors from road design and the position of parks to individual houses and gardens, Dr March says.
“We need to bring all that together. ….what we find is if one of those factors is not right, the whole thing can fail. Fire tends to find the weak point in what we do.”