Nutrient situation at groundwater measuring points in Lower Saxony

Trend observations for the parameter nitrate for the period 2016 to 2021 were carried out at 1,097 measuring points in groundwater. The groundwater maps indicate a trend when the result is statistically significant and the mean of the measured concentrations at the measuring point is > 5 mg/l. For measuring points with a mean nitrate value For groundwater, evaluations of the parameter nitrate are included. The threshold value of 50 mg/l is the specified quality standard for groundwater (Groundwater Ordinance) and corresponds to the limit value for drinking water according to the Drinking Water Ordinance. Groundwater with a minor agricultural influence has nitrate levels below 10 mg/l. Concentrations of well over 50 mg/l can occur in intensively used agricultural regions.