Global trends

The data FreshWater Watchers collect is consistent in every location around the world. This means we can use the data to explore worldwide trends in freshwater health. With this overview we can work with national governments and international organisations to identify where common improvements can be made, helping to drive global change.

FreshWater Watchers have taken measurements from across the globe, recording the conditions of our freshwater ecosystems. Their efforts are being used to improve and monitor our environment in the face of climate change, intensive land use and urbanisation. Over 24,000 measurements have been taken from more than 2,000 water bodies in 26 countries worldwide.

The data shows that nutrient pollution is a major international challenge. This eutrophication (high nutrient concentrations) leads to biodiversity loss, harmful algal blooms and lower quality water.

Globally, 30% of the water bodies measured have evidence of nitrate pollution (concentrations higher than 2 ppm N-NO3), and 25% showed evidence of phosphate pollution (concentrations higher than 0.2 ppm P-PO4).


These data vary significantly from country to country and by water body type and size. In general, small lakes and ponds have better conditions than larger rivers. Countries with less of a history of agricultural activity, like Singapore, Zambia, and Australia, have fewer water bodies with nitrate pollution. Countries with high populations and limited wastewater treatment tend to have higher phosphate concentrations.


We are now exploring how the data our citizen scientists collect can be used to monitor progress towards UN Sustainable Development Goal 6. This way we can ensure that FreshWater Watchers across the globe are providing data to help improve the health of freshwater ecosystems worldwide.