Filter Drains - Overview

Also referred to as French Drains, Filter Drains are shallow linear trenches filled with granular filter material. They can be used to create temporary subsurface storage for the attenuation, conveyance and filtration of surface water run-off – usually receiving lateral inflow from an adjacent impermeable surface that has been pre-treated via a filter strip.

Where increased management of ponding and/or flooding is required, added drainage can be achieved via the inclusion of a perforated pipe. In more extreme events, substituting the pipe with a Polystorm Geocellular system delivers a Polypipe Plus system with higher storage and attenuation capabilities.