Innovative stormwater management can help improve quality of life for communities
by Ruth Cooper
Traditional approaches to stormwater management are being reconsidered in favour of strategies that reintegrate runoff back into the urban environment and help create sustainable green spaces.
Ahead of her keynote address at the Australian Water Association South Australian State Conference, Water Sensitive SA program manager Mellissa Bradley said the industry should shift its thinking to reintegrating water back into the urban environment, particularly as urban infill increases.
“If we’re making an area impervious, we need ways of dealing with the extra stormwater runoff and we’re running out of park space to have big detention basins. The more we can do source control, the less water has to end up in the local park to be managed,” she said.
“It’s changing the thinking about treating stormwater – not at the end of the line but managing it all the way through the catchment.”
This is particularly important in South Australia, where the government’s 30-year Living Adelaide plan has outlined targets of 85% urban infill and a 20% increase in urban green cover in metropolitan Adelaide by 2045.
“[Increased urban infill] presents an immense number of challenges. Not only how we manage stormwater that runs off these sites, but having the space to treat stormwater and having green infrastructure,” Bradley said.
“That’s where we need the innovation – in the urban infill landscapes. How those developments interact with the streetscapes is where the opportunities are. And with people having smaller backyards we need to put more emphasis on the public realm and what that offers people because that’s their main place to recreate.”
One solution is harvesting and reusing stormwater at the source. This means collecting water in the streetscape, local parks and through roads with permeable paving, and channeling it back into the environment.
“We want to use that water to sustain healthy street trees and parkscapes … By having active green spaces that are sustained by water – often alternative water – we can create opportunities for communities to connect with each other physically but also create better spaces that people want to be in,” Bradley said.
Unlike infill developments where planners have to work around existing systems, it’s easier to integrate water sensitive design into greenfield development sites.
At Lightsview in Adelaide's northeast, each house has ‘reWater’ – a combination of recycled stormwater and groundwater supplied by Salisbury Water – plumbed for toilets and outdoor use. This water is also used to irrigate the neighbourhood’s street trees and verges, which Bradley said has helped to create “one of the greenest suburbs you would see”.
“Even though it’s a medium density suburb – a lot of the blocks are probably 90% impervious – the high standard of the streetscapes and parks makes a really big difference to the quality of life of the people who live there,” she said.
“They may not have their own private backyards, but they’ve got access to good green spaces because of the alternative water.”
Bradley also pointed to the City of Mitcham’s use of permeable paving as an example of innovative stormwater management helping to create sustainable green spaces. The council has installed permeable paving to both manage flooding and harvest water for street trees and parks.
“They had a 1 in 50-year event come through and no houses flooded, all the water just seeped through and was reintegrated back into the environment … The overflow from the permeable paving is collected in drains underneath the road and fed into an adjacent park where it sustains the trees and provides resilience against drought,” Bradley said.
“Innovators like this who are trialling things and putting themselves out there and saying they want to do things differently are really paving the way for the rest of the industry.”
Mellissa Bradley will be presenting at the upcoming 2018 South Australian State Conference on leadership in water. To learn more and to register, click here.
Related podcast:
https://omny.fm/shows/australianwater/shona-fitzgerald-on-liveability
