Water Quality Objectives

Summary

There are no detailed legal standards for the quality of rivers or drinking water in the UK. River quality is often assessed by classifying rivers either according to their chemical composition or according to the variety of river life present. Water authorities have been advised to set ‘river quality objectives’ for their rivers based on their actual use. For some rivers this may mean that the long-term aim will no longer be to improve them to the highest standards.

River quality can also be assessed by comparing the amounts of toxic substances present to those known to be harmful to fish life. Although the EEC has proposed legally enforceable fish protection standards for rivers, the UK government maintains that these are unnecessarily stringent.

Drinking water is often taken from rivers that have been contaminated by sewage or industrial effluent. Water authorities are required by law to provide ‘wholesome’ drinking water and normally follow standards recommended by the World Health Organisation. Tap water in some parts of the country sometimes contains more lead or nitrates than these standards allow. Many other households receive water that fails to meet new drinking water standards that have been proposed by the EEC. Another potential source of hazard may be caused by the tiny traces of chemicals recently found in drinking water. In large concentrations, some of these substances are known to cause cancer in animals.