Catchment to Coast rain gardens
Raingardens funded by Rain Garden 500
Left to right: Halmon Ave,Everand Park; RAA, Pymbrah Street Carpark, Mile End; and Flagstaff Hill R-7 School, Flagstaff Hill
The Catchment to Coast Project, funded through the Australian Government National Landcare Program included Rain Garden 500, a 3-year grant program between 2015 and 2018 where local councils, community groups, schools, sports clubs, or a group of motivated individuals could apply for funding to build a rain garden in the Adelaide region. At its conclusion, Catchment to Coast funded 32 projects, across 11 council areas, including 2 businesses and 2 schools.
The purpose of the rain gardens is to improve the quality of stormwater from our streets and other hard surfaces such as car parks, before it travels to our local creeks and the sea. The improved stormwater from the rain garden may be collected and used for irrigation or returned to the stormwater system.
Collectively rain gardens and other stormwater improvement features such as wetlands installed in catchments will contribute towards less stormwater going out to sea and improved water quality in urban waterways and Adelaide’s coastal waters. This will reduce pollution, and contributes to improving seagrass health benefitting our marine environment and keeping our beach water cleaner.
An important component of the project was to build an understanding in the community of how the actions we carry out on land impacts water quality in urban waterways, creeks and coastal waters. A focus of Rain Garden 500 was the importance of improving stormwater quality and where and how rain gardens installations may be incorporated. It allowed local communities to contribute to improved stormwater quality and ultimately seagrass health. We can all take action at our local street and community level to improve water quality.
What is a rain garden?
A rain garden is a constructed garden designed to capture stormwater from roads, carparks, driveways, rooves and other hard surfaces. Rain gardens are water sensitive urban design features that may be used to better manage stormwater. Beneath the surface of the rain garden is a special porous soil layer (filter media) overlaying a drainage layer.
The stormwater is detained in the rain garden through the design and vegetation, slowly filtering through the soil layer to the drainage at the base. Stormwater flows are diverted and pollutants are removed through the processes of settlement (sedimentation) binding with components in the filter media and by the action of specially selected plants and the associated microbial community. They can be scaled to various catchment sizes from a single small garden or part of a larger project to manage stormwater. The improved stormwater from the rain garden may be collected and used for irrigation or returned to the stormwater system.
Even if you do not install a rain garden there are actions you can take that will improve stormwater quality and ensure only rain goes into stormwater drains.