Water quality in watercourses

Water quality in watercourses has improved significantly since the 1970s in terms of nutrient pollution. Micropollutant contamination is the new and biggest challenge at this time.

Bathing water quality

Thanks to various protective measures and major advances in wastewater treatment in recent decades, water quality in Swiss rivers and lakes is now very high and virtually all are clean enough to swim in.


From a biological perspective, the state of Swiss watercourses is good, but at varying degrees. The results of the National Surface Water Quality Monitoring Programme (NAWA) show that the ecological functionality of water bodies is insufficient at no fewer than 30 percent of measuring stations.Problems exist particularly in the intensively used Central Plateau, where bodies of water are structurally impaired and fish are unable to migrate in several areas.


Micropollutants make their way into bodies of water with treated wastewater and through diffuse inputs from sources such as agriculture. They can adversely affect marine biotic communities, even in low concentrations.

Nutrients in water

Nutrient pollution in rivers and streams has fallen significantly in Switzerland. The target values are still occasionally exceeded in agricultural and settlement areas, and international water protection targets for the Rhine River have still not been met for nitrate.

Heavy metals

Heavy metal pollution in Swiss watercourses is on a downward trend.

Last modification 30.08.2018

Top of page