We were struck by the severity of flooding across Australia’s eastern coast recently, and the vulnerability of our communities to severe weather. Extreme weather events are projected to increase in frequency due to climate change, which threatens public safety and burdens our stormwater infrastructure.
In a dire race to protect our community’s waterways, stormwater infrastructure is undergoing a revolution of new green technology.
Capturing, diverting, and absorbing stormwater runoff is the basis of contemporary city-planning solutions. This approach is now the driving philosophy behind new developments in historically flood-prone cities like Copenhagen, New Orleans, and New York.
Shifting Our Mindsets Around Stormwater
The movement of water is a natural process. However, our urban centres are full of impermeable surfaces, such as concrete and bitumen. With nowhere for stormwater to seep into the ground, stormwater often has no recourse – pooling or rushing to find our drains and waterways.
Before development, natural habitats like wetlands, swamps and vegetation acted as flood control with their inherent capabilities to absorb and slow stormwater. Unfortunately, much of these natural habitats have been lost to urban sprawl.
We are facing an increasing need for wider and deeper drainage networks. This approach is unsustainable – how are our overburdened stormwater systems meant to keep up?
Countering conventional thinking, which drains stormwater from urban centres as quickly as possible, many modern technologies look to slow down moving stormwater and allow it to permeate the ground slowly.
Blue-Green Infrastructure: Designing Cities that Handle Water
To future-proof our urban environments, we need to conserve and create spaces that allow us to coexist with localized water events. Bluegreen infrastructure is recognised as a multifunctional stormwater and flood mitigation design concept and is being adopted across certain municipalities in Australia.
Besides parks, gardens and green space, we can incorporate innovative and specialised vegetated areas such as swales, bio-retention basins, and floating wetlands. For example, SPEL’s SQIDEP approved SPELBasin shows the ways we can blend natural and urban infrastructure to naturalize urban water flows. We also design special bioretention media, SPELBio, that is specifically designed to help slow down water flow and act as a growth medium for pollutant capturing plants.
Adding value to surrounding areas, these places not only absorb water but often share functions as public amenities, habitat for wildlife and urban green space. Stormwater infrastructure is fast becoming a standard feature in community-wide development plans.
At SPEL Stormwater, we have had the privilege of working on many open space projects that incorporate stormwater storage beneath sports fields, parking lots, and transport depots. One of our most recent projects includes the inner-Canberra bus interchange facility in Turner. For the facility, we installed a 2-million litre detention system that would reduce flooding impacts on the surrounding area.
Baffle box installations are another great solution to help handle the impacts of surging floodwater, as the torrents pick up sediment, debris, and trash in urban areas. SPEL’s Baffle Boxes have been installed throughout Australia – from Geelong to Rockhampton – to help support clean waterways. Ultimately, they reduce the amounts of pollutants and particulates entering key water bodies during flood events – for example, Queensland’s Great Barrier Reef and Moreton Bay.
When planned and designed well, green-blue infrastructure can help to solve urban and climatic challenges through the provision of ecosystem services that enhance the well-being and prosperity of local communities. Together, we can get on top of stormwater solutions that mitigate floods and reduce the impacts of climate change on our communities. SPEL hopes to raise awareness of the ways stormwater assets can help us prepare for the future and lead the way with innovation and sustainability.