A Reed Bed Wastewater Filtration System is constructed using planted reed vegetation floating on top with the roots embedded into sand bed or rock layer at the bottom to form narrow trenches and allow wastewater or sludge to pass through beneath the plants’ bacterial populated rhizome network. The bed will usually come complete with an underdrain piping system located below the supporting bed to collect back the percolate and return it to the treatment plant for further processes. The system has several uses mainly that acts as a tertiary biological purification option to filter and improve the quality of wastewater or in other applications, can also be applied towards control of landfill generated leachate. Apart from that it is also a workable solution for sludge dewatering purpose which has become a standard practice largely used in Europe and North America.

Compared to sand drying beds for sludge dewatering, this setup has several advantages, the fact that it can withstand sludge accumulation and hold on with this current condition for several years without affecting performance and degrading the capability to treat high COD load. Sand drying beds on the other hand, would always require immediate attention to remove accumulated solids or else the crust that forms on the surface will drastically affect the water evaporation. The only problem that affects efficiency in reed bed process is that the wastewater feed to the unit should have low organic content or else, it will overwhelm the treatment capability of the reeds and in worse case situation will kill the vegetation. Normally depending on whether the feed wastewater sludge is aerobically or anaerobically digested in the earlier processes, the solid should not exceed 4% or else with increased loading rate, it will prevent the system from operating at its peak.
Design and construction of the reed bed treatment facility is very much similar to the sand drying beds and the material needed for the setup can be easily sourced locally without escalating the project cost. These days there are even small-scaled plants which can be easily built to serve residential and individual home treatment requirements like sewage and generation of effluent wastewater. Usually for those systems that are built and operate as part of a large treatment facility, special considerations have to be carefully studied with possible cases related to seepages and how to prevent incidence of groundwater contamination. Thus it is important that there should be a liner put in place and with groundwater monitoring wells used for periodic checking of the water quality.