This chart is compiled from weekly analyses which are averaged to produce quarterly results for each of the sampling sites. You can find all our previous years’ quarterly results on our Data Logger – just scroll down for the link to this.

Measurement units: milligrams per litre of sampled water (mg/l).

There is considerable variability in environmental nitrate levels within water bodies. There is a UK standard of a maximum of 50 mg/l for nitrate in drinking water, which is shown as the horizontal line on the chart.