Reed bed types
A vertical flow reed bed is made up of layers of various sized gravel. The largest is at the bottom, decreasing to sharp sand at the top into which the Common Reed or similar plants are planted.
In the vertical flow system the effluent must be spread evenly over the reed bed surface. Some vertical flow systems have a network of perforated pipes surrounded by large stones to encourage even distribution. Even so, regular if not daily supervision of the system is required to prevent the build up of biomass on the surface of the reed bed or saturation of the gravel layers, thus preventing downward movement of the effluent. This can lead to ponding and could result in a nuisance smell and constitute a possible health risk
Horizontal flow reed beds have a much larger footprint than vertical flow beds. They are shallower and constructed in a completely different way. The effluent enters at one end, immediately sinks below the surface before travelling horizontally through the gravel and root zone of the Common Reed or similar plants.
This system requires much less work. An occasional weeding of tree seedlings and other plants is all that is required on a regular basis. Should the reeds begin to look a little tired they could be cut back and the debris cleared to increase vigour.
Horizontal reed beds require little maintenance and have a reduced discharge in the summer.
Freshly planted reed bed.
Hard working reed bed.
A matured reed bed.