Focus on river discharges

The Netherlands Court of Audit has investigated the concentration of 15 harmful industrial substances in Dutch surface water that are a risk to human health and the environment. As an EU Member state, the Netherlands has undertaken to reduce the presence of these substances by 2027. The 15 substances are among the most harmful of the 122 harmful named in the Water Framework Directive (WFD) that must be brought below the agreed standard by 2027. The investigation found that no progress has been made on most of these 15 substances in recent years. 

Government reports on chemical water quality in the Netherlands give only limited insight into whether our water is becoming cleaner. They state whether European standards have been breached, but the standards change over time. That is why the Court of Audit not only looked at pollution breaches but also examined the surface water concentration of 15 of the 122 harmful industrial substances named in the WFD. They include carcinogenic PAHs (polycyclic aromatic hydrocarbons), PFOS, heavy metals such as lead and mercury, and dioxins. Incidentally, pollution of surface water has several causes; in addition to industrial discharges, there is pollution from precipitation and pollution via water that flows in from abroad. 

No decline in concentration of most harmful substances

Our investigation relied on data on the concentration of the 15 harmful substances at all 61 monitoring stations in Dutch national waters. The figure on the left below shows the number of monitoring stations where each of the substances did and did not comply with the standard in 2023/2024. 
Under the WFD, if one substance breaches the standard, the chemical quality of the surface water in question is inadequate.
 

Social and economic damage, risk to drinking water

Natuur & Milieu estimated in 2025 that industrial pollution cost the Netherlands at least €7 billion a year. The Court’s Board member Barbara Joziasse said, “Our investigation found little progress in tackling harmful industrial substances in surface water. Surface water pollution can have consequences for human, animal and plant health and puts pressure on drinking water supplies. The cost of water treatment can run into billions and is increasing. Water withdrawal from the Meuse has had to be stopped several times in recent years because of the poor quality. In addition, if we do not meet the European standards we committed to in 2000 by 2027, there is a risk of fines from the European Commission or cuts in European funding.”

Limited insight into permits and discharges

The Minister of Infrastructure and Water Management is responsible for issuing permits for industrial discharges into national waters. Compliance with permit conditions is monitored by Rijkswaterstaat (RWS). Our investigation found, however, that the minister has little insight into what is being discharged by which companies. RWS does not have a central data system with an up-to-date record of the companies, permits, and permitted and actual discharges. As a result, it is not possible to paint a national picture of which companies discharge into national waters and whether the discharges are permitted. 

Why we carried out this investigation

Almost no surface water in the Netherlands meets the quality requirements of the Water Framework Directive (WFD). The WFD focuses on protecting and improving the quality of surface water and groundwater. Its aim is to achieve a good ecological and chemical balance in all water bodies in the EU by 2027. The latest WFD progress report shows that no Dutch waters are in good chemical condition and that the Netherlands will not meet WFD targets by 2027. 

Focus investigation

This report presents the findings of a focus investigation carried out by the Netherlands Court of Audit. A focus investigation differs from an audit in that it is carried out in a considerably shorter period of time, examines current events and answers specific, well-defined questions. A focus investigation culminates in a clear, concise report without opinions or recommendations. For more information, see Focus investigation.