Historically stormwater was thought of as a nuisance, creating potential risk to life and property. Naturally, the stormwater management approach which evolved focused on draining urban areas as quickly as possible during rainfall events. This approach has been very effective in flood mitigation, but unfortunately, equally effective in washing large amounts of stormwater and pollution directly into our natural waterways.
Declining water quality and ecological health in urban waterways together with recent drought conditions led stormwater managers to review traditional approaches to managing stormwater. The focus stayed on flood mitigation, but grew to include the preservation and restoration of urban waterways as well as the use of stormwater as a resource.
This review process saw the birth of Water Sensitive Urban Design (WSUD) in Perth during the early 1990s, a new approach to stormwater management which has since spread across Australia, continually evolving along the way.
Traditional stormwater management - draining urban areas quickly as possible during rainfall events for flood mitigation
WSUD is all about:
- reducing the amount of stormwater runoff in urban areas;
- extending the time it takes for stormwater to reach natural waterways;
- reducing the amount of pollution entering natural waterways; and
- providing alternative water supply options for urban areas.
WSUD does this by cleansing and reusing as much stormwater as possible before and after it flows down drains, and by allowing time for stormwater to soak into the ground and even evaporate a little.
Image ©Healthy Waterways Ltd
The range of WSUD treatments includes swales, bio-retention systems, porous paving, gross pollutant traps, infiltration trenches, constructed wetlands and rainwater tanks. Treatments are sometimes used on their own, but often combined to create a treatment train.
But these treatments don’t just provide water quality improvement, flood mitigation and alternative water supply options. The vegetated treatments also make great natural features in parks and streets in our neighbourhoods.
A new approach to stormwater management - WSUD incorporated into traditional stormwater management practices to reduce pollution, provide alternative water supply options and help mitigate flooding
Urban areas around Australia are currently at varying stages of putting WSUD into practice, and NRM North is working with Councils, industry and the community in our region to help this process.
If you’re thinking about installing a WSUD treatment, or would like to learn more, why not check out our stormwater quality improvement tools and resources.
Check out the videos below to learn more about WSUD in Tasmania's Northern NRM region.
Bioretention basin - Tyler Village, Prospect Vale
Scottsdale WSUD Treatment Train