Downstream Defenders

Marshalls Civils & Drainage in a joint venture with Hydro International has introduced a Stormwater treatment system called the Downstream Defender®, an advanced hydrodynamic vortex separator.

The Downstream Defender® is an advanced hydrodynamic vortex separator for the effective and reliable removal of fine particles along with oils and other floatable debris from surface water runoff.

Its innovative design delivers high efficiency across a wide range of flows in a much smaller footprint than conventional or other swirl-type devices and is the perfect choice for any catchment likely to convey high quantities of contamination.

Targeted Pollutants:

  • Fine particles.
  • Gross pollutants.
  • Liquid and sediment bound hydrocarbons.
  • Sediment bound heavy metals.
  • Sediment bound nutrients.

The Downstream Defender® has unique flow modifying components that have been optimised to deliver unsurpassed capture and retention of pollutants during both frequent and extreme rainfall events.

The Downstream Defender® delivers high removal of pollutants through advanced hydrodynamic vortex separation across a wide range of flows, achieving a long, stable flow path to maximise pollutant capture from surface runoff.

The devise is able to tackle an assortment of pollutants including gross debris, litter, hydrocarbons, coarse sediments, fine sediments and particulate organics.



01179 814500

Certification Logos and Accreditations

  • Accreditation ISO 9001 Logo
  • Accreditation ISO14001 Logo