Phosphates in freshwater: standards for nature conservation (ENRR073)

English Nature produced proposals for a series of water quality criteria based upon a range of values of orthophosphate and ammonia concentrations and Biochemical Oxygen Demand, for the Special Ecosystem Use Class. It is envisaged that these criteria would be applied on a case-by-case basis to protect the specific nature of the river and its ecology, over and above the protection to be afforded by the Fisheries Ecosystem Use Class.