In many places, the groundwater and surface water still contains too much nitrogen and phosphorus. As a result, the Netherlands is failing to meet the targets of the European Nitrates Directive. Due to an excess of nitrogen and phosphorus, the biological water quality in many bodies of water in the Netherlands is not sufficient, and the quality of drinking water in some parts of the Netherlands is under pressure. Improving groundwater quality is especially important in the Sand and Loess region. This is according to the report Agricultural practices and water quality in the Netherlands 2020–2023.
The substances nitrogen and phosphorus improve crop growth. When farms use fertiliser, excess nitrogen and phosphorus leach into the groundwater and surface water, causing pollution. Nitrate is the most common form of nitrogen in the soil and water. This report outlines the development of nitrate concentrations in groundwater and surface water and total nitrogen and phosphorus concentrations in surface water.
Groundwater results
This report provides insight into the effects of the policy measures (until 2022) on the water quality. The water quality has not structurally improved since 2012. Between 2020 and 2023, nitrate concentrations in groundwater under farms increased compared with 2016–2019. According to the European standard, the nitrate concentrations are still too high for more than half of the farms in the Sand and Loess region. This is partly due to the dry summers of 2018 to 2020. During dry periods, crops absorb less nitrogen, resulting in more nitrogen being left in the soil. Nitrate concentrations have been declining since 2021 but are still higher in these areas than they were in 2018.
Surface water results
Due to an excess of nitrogen and phosphorus in surface water, the biological water quality in many bodies of water in the Netherlands is not sufficient. Among other things, this can lead to too few different species of plants and animals in those habitats. The biological water quality is not sufficient in 44% of the bodies of water in the Netherlands, partly due to fertilisers. In 11% of the bodies of water, there are still sufficient species of plants and animals, but nitrogen and phosphorus concentrations are nevertheless too high.
Drinking water quality under pressure
Clean groundwater and surface water is important for drinking water production, which is why it is important to improve water quality. Nitrate is a problem for drinking water sources in sandy soils in particular. Groundwater that contains more than 50 milligrams of nitrate per litre is less suitable for processing into drinking water. There are already problems, or problems are likely to develop in the near future, at around 20% of groundwater extraction points.
European Nitrates Directive
The goal of the Nitrates Directive is to protect drinking water sources and to prevent the pollution of surface water by fertilisers from agricultural sources. Every four years, RIVM, together with RWS, Deltares, CBS, WEcR and RVO, reports on the use of fertilisers in agriculture and its effect on the quality of groundwater and surface water. With this report, the Netherlands is reporting on the progress of improving water quality to the European Commission.