Formerly Spel Hydrosystem

FlowFilter is a specialist stormwater filtration system that is purpose-built to reduce the footprint of WSUD on constrained projects. Manufactured, designed, and engineered in Australia using fibre-reinforced polymer (FRP) this generational asset is supplied with a 25-year warranty & 100-year design life.

This innovative approach to stormwater treatment uses an up-flow filtration process. With minimal head drop required between inlet and outlet, these devices are suitable for installation on flat sites or low gradient developments. The stormwater is treated within the unit by the following processes: sedimentation, filtration, adsorption, and precipitation.


  • Manufactured, designed, and engineered in Australia at our FRP production facility
  • Lightweight, easy to install and minimal on-site lifting requirements (no crane required)
  • Reduced on-site footprint
  • Up-flow filtration process suitable for flat sites requiring only 250 mm of hydraulic head
  • Scalable sizes with variable cartridge configurations from 1 to 39 filter cartridges
  • Treatment flow rates from 2.5 litres per second (LPS) to 156 litres per second installed in offline configuration
  • Custom-designed inline systems available
  • Installed in trafficable and non trafficable applications


  • Car parks & shopping centres
  • Council depots
  • Industrial estates
  • Heavy vehicle maintenance
  • Transport depots & loading bays
  • Tunnels
  • Highways & transport corridors
  • Recycling yards
  • Airport aprons & tarmacs
  1. Stormwater from catchment enters the offline Hydrosystem inlet.
  2. Sediment is retained within the sump area.
  3. Filter cartridges operate in an up-flow process. The fine sediment is physically removed, and dissolved pollutants are precipitated and adsorptively bound to the filtration media.
  4. Treated water flows from cartridges to outlet and into downstream water network.


Case studies, webinars, projects, media and social media updates.

Scroll to Top