The  Filterra® System is a revolutionary rapid bioretention system that is designed to capture, treat and remove a variety of pollutants in stormwater runoff. Filterra is well suited for the urban and high-density environment providing a highly effective, natural treatment process packaged inside a flow-through container that can be easily installed at new or existing commercial, residential and public roadway projects

The system is an engineered biofiltration device with components that make it similar to bioretention in pollutant removal and application, but it has been optimised for high volume/flow treatment and high pollutant removal.

The Filterra® system works as efficiently as a traditional rain garden but in a footprint a fraction of its size. 


How does it work?

Filterra is a bioretention system in a concrete box.

Contaminated stormwater runoff enters the filter box through the curb inlet spreading over the 75 mm layer of mulch on the surface of the filter media. As the water passes through the mulch layer, most of the larger sediment particles and heavy metals are removed through sedimentation and chemical reactions with the organic material in the mulch.

Water passes through the soil media where the finer particles are removed, and other chemical reactions take place to immobilize and capture pollutants in the soil media. The cleansed water passes into an underdrain and flows to a pipe system or other appropriate discharge point.

Once the pollutants are in the soil, the bacteria begin to break down and metabolize the materials and the plants begin to uptake and metabolize the pollutants. Some pollutants such as heavy metals, which are chemically bound to organic particles in the mulch, are released over time as the organic matter decomposes to release the metals to the feeder roots of the plants and the cells of the bacteria in the soil where they remain and are recycled. 



  • Offers the most cost-effective stormwater treatment system, featuring low-cost, easy installation and simple maintenance
  • Meets regulatory requirements for pollutant removal under TAPE and TARP testing
  • Enhances the appearance of your site, while removing pollutants
  • Maintenance is simple and safe, with no confined space access
  • Ideal for both new construction and urban retrofits, streetscapes, parking lots, day-lighted roof drains, highways and industrial settings