What do we see?
The graph below shows how the average nitrogen concentration in surface water has evolved in recent years. We also see in how many measurement sites the threshold value (50mg NO3/l) has been exceeded at least once. In the winter of 2019-2020, this occurred in 32% of the measurement sites. Despite this, we cannot really identify any trends for the majority of the measurement sites between 2010 and 2020. We do see a significant decrease in 15% of the cases, but we also see a significant increase in 7% of the measurement sites. A possible explanation for this increase is the droughts of 2017, 2018 and 2019, which meant more fertilisers ended up in the environment.
What’s the aim?
In a circular model, we aim for closed material cycles. Not just because this reduces the demand for new input but also to avoid unwanted damage to the environment (e.g. through leaks). Human activities are responsible for high concentrations of substances including nitrogen and phosphate. The excessive amounts have a major impact on our environment. In water, this leads to eutrophication, which not only disrupts the ecosystem but also has a negative impact on our drinking water.
What does this indicator measure?
This indicator shows the evolution of the amount of nitrogen in surface water in the agricultural regions of Flanders. It also indicates where the threshold value (50mg NO3/l) has been exceeded at least once. The data is collected by the Flemish Environment Agency based on their network of measurement sites. The figures from the 760 measurement sites are evaluated between 1 July and 30 June each year (which counts as the winter).