B4.8 Water Quality Standards
The Environment Agency used to use General Quality Assessment (GQA) scheme to assess river water quality in terms of chemistry, biology and nutrients. The GQA helped drive environmental improvements by dealing with many of the major point sources of pollutants, such as discharges from sewage treatment works or other industry.
However, now a more sophisticated way of assessing the whole water environment is required. One that will help the Environment Agency direct action to where it is most needed.
The Environment Agency state that the WFD will provide this mechanism, by looking at over 30 measures, grouped into ecological status (including biology as well as specific issues such as phosphorus and pH) and chemical status (the priority substances).
A single tree will give off 265 litres (70 gallons) of water per day in evaporation.