What is a rain garden?
A rain garden, or biofiltration system, is an garden that is engineered to filter and treat stormwater so that it is clean before is leaves the system and flows into the 'receiving waters' which may be an ocean, lake, river or stream. In the case of the Addison Road Centre, all stormwater flows into the Eastern Channel North before making it's way to the Cooks River then out to Botany Bay.
A rain garden looks much like a normal landscaped garden except that it has a bowl like shape to hold water before it filers through the layers of sand and gravel, and it is planted with species that are particularly good at filtering out and removing pollutants. Australian native grasses and sedges are particularly good at this, so there is also a native habitat benefit when a rain garden is installed. Our local native species are also very good at going for long periods without rain then being inundated during a strorm. They have really adapted very well to our local climate!