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

Aerial view of geo-engineering applications of a modified zeolite product called Aqual-P at Lake Okaro, New Zealand.
Assessing geo-engineering approaches
Dr Andrew Singer
A growing problem for human and animal health
table of chemical risk ranking
Identifying the single most dangerous chemical present in UK surface waters
River Thames at Lechlade on sunny day
A cause for concern but also a challenge for modelling methods?
Austria Center Vienna photo: Marcus Winter (CC BY-SA 2.0)
International geosciences conference
River Thames in London
Thames Basin part of international study
Endocrine map - Rivers
Professor Andrew Johnson talks about chemicals and the environment
eLTER H2020 project logo
Integrated European Long-Term Ecosystem & Socio-Ecological Research Infrastructure