Water quality standards or carbon reduction: is there a balance?

Currently there is a misalignment between the European Union Water Framework Directive (EU WFD) and the United Kingdom Climate Change Act (UK CCA). This paper explores the tensions and complexities experienced by water companies in England and Wales as they attempt to meet the contradictory legislative requirements. A simple model is used to explore the effect of increasing effluent quality on power consumption and hence carbon emissions. Further data are collected through interviews and textual analysis to dissect opinions and views on the dilemma facing the water industry. In addition to complexities within the EU WFD and UK CCA, water companies are restricted by the regulatory framework of the UK water industry and additional policies and directives. Through this research, numerous suggestions offered by key stakeholders in the industry are explored. Among the proposed solutions is process optimisation of aeration, during activated sludge treatment. This does not require additional changes to legislation and may form one of the principle solutions because it is able to reduce emissions immediately. However, recent research has shown that aeration optimisation may cause increased emissions of the greenhouse gas nitrous oxide. This must be taken into account when finding the optimal solution.