Constructed Wetlands: A Strategy for Sustainable Wastewater Treatment at Small Treatment Works

The use of sub-surface flow constructed wetlands planted with Phragmites australis (the common reed) for the treatment of sewage is now widespread in the UK. The strategy for the use of reed-beds by a major UK water utility is reviewed in terms of whether the process (a) is appropriate within the rural environment, (b) offers satisfactory performance, and (c) meets criteria for sustainability. Its use for secondary, tertiary and storm-water treatment is considered. Odour generation has been a concern for secondary treatment reed-beds and has been measured and modelled to identify the required minimum distance to properties to eliminate any possibility of odour nuisance.