The Water Framework Directive (WFD) came into force in 2000 and is the most substantial piece of EU water legislation to date. It intends to safeguard and improve water quality and looks at the condition of things living in the water in order to determine water quality.

The directive requires all inland and coastal waters to reach "good status" by 2015. It will do this by establishing a river basin district structure within which environmental objectives will be set, including ecological targets for surface waters.

The regulations set out in the directive apply to all surface freshwater bodies (such as lakes, streams and rivers), groundwaters, groundwater dependant ecosystems, estuaries and coastal waters out to one mile from low-water.

As well as improving the ecological health of inland and coastal waters and preventing further deterioration, the directive also hopes to encourage wiser, more sustainable use of water as a natural resource.