Water quality refers to the biological, chemical and physical makeup of the water. There are always natural changes in water quality, but industrialisation, population growth, climate change and land-use change have meant more pollutants are entering water systems than ever before. These pollutants alter entire ecosystems and present a danger to human health.

This pollution can be very sudden and dramatic - the BP oil spill made headlines for months. Other pollution, however, is sometimes harder to spot. Nitrogen and phosphorous, for example, quietly enter the environment as by-products of industrial processes. The resulting nutrient-rich water system can actually be harmful for aquatic life, with algae using up all the oxygen and creating ‘dead zones’.  

There is also the financial cost and the toll on human health. Nitrogen pollution alone costs Europe an estimated £60-280 billion per year, and about 10 million Europeans drink water with unsafe levels of nitrate.

CEH work on water quality


Monitoring sites

Research facilities

River Thames bankfull 2007
Urban growth has an impact on river flows and water quality
Detail from Land Cover plus Crops Map 2015 showing crop types
Digital mapping of arable cropping on an annual basis
Ganges river, India
Outputs of December 2015 Science Workshop
Ganges near Haridwar. Photo: Mike Acreman
UK-India workshop on future research needs to underpin sustainable management of the Ganga
A boat at Derwentwater
Long-term science in a galaxy far, far away...
FEH Supplementary Report cover
Online access replaces CD-ROM
Windermere from Wansfell
Promoting evidence-based lakes management
riverside vegetation
Managing colour levels in drinking water
Black darter dragonfly photo: Ross Newham
Record sightings to support study and conservation