What is a biofiltration system?
Water biofiltration is the process of improving water quality by filtering water through biologically influenced media. Stormwater biofiltration systems are known as biofilters, bioretention systems and raingardens.
A typical biofiltration system consists of a vegetated swale or basin overlaying a porous filter medium (usually soil-based) with a drainage pipe at the bottom. Stormwater is diverted from a kerb or pipe into the biofiltration system, where it flows through dense vegetation and temporarily ponds on the surface before slowly filtering down through the filter media.
What is a raingarden? Source: Resilient East
Types of biofiltration systems
Streetscape raingardens
Jarman Terrace, Flinders Park
Biofiltration basins
Unity Park, Pooraka
Biofiltration swales
Dover Street Reserve, Aldinga
Why choose a biofiltration system?
As at 2013, it was estimated (that stormwater contributed 6,180 tonnes of sediment (77% of total annual load of sediments to marine waters) and 150 tonnes of nitrogen to the Gulf St Vincent every year. (Adelaide Coastal Water Quality Improvement Plan ACWQIP PDF, EPA 2013). Biofilters have been proven to be effective at removing pollution transported via stormwater runoff before it reaches our waterways and coastal environments.
Technical resources
Standard drawings