The Human Environment and Transport Inspectorate ( ILenT) is the regulatory authority in this context. ILenT assesses whether the drinking water meets these requirements and publish their results in the annual report: ‘The quality of drinking water in the Netherlands’. The quality of drinking water nearly always meets the set requirements, achieving that standard in over 99.9% of all measurements.

RIVM manages the collected data on water quality and supplies the information for the annual report to IlenT. Until 2012, RIVM also produced a more extensive annual report on this topic.

Drinking water sources

Drinking water in the Netherlands is of  very high quality. However, there is cause for concern regarding the quality of the sources of drinking water. In the Netherlands, 60% of drinking water is produced from groundwater and 40% from surface water. In total, there are approximately 200 locations in the Netherlands where groundwater and surface water are abtracted for drinking water production. According to current guiding principles in national and international policy, such as the European Water Framework Directive, water sources should be of sufficiently high quality that they can be used to produce drinking water using simple techniques. This is currently the case for approximately half of all groundwater extraction points in the Netherlands. The other groundwater extraction points are influenced by human activities, such as agriculture, sewage systems, industry and lingering soil contamination, and therefore do not comply with this standard.

Surface water quality is similarly compromised. Water Quality has improved in recent decades by decreasing emissions from industry and agriculture, but not to the extent that these emissions are no longera problem. The main concerns at this point are substances that consumers use, such as medication, insecticides, biocides, cosmetics, flame retardants and nanoparticles. Wastewater treatment plants are not yet able to eliminate these substances effectively . As a result, they end up in the environment – and therefore also in drinking water sources. Drinking water companies use increasingly advanced purification techniques to remove these consumer substances. The very low concentrations that remain do not pose a risk to public health. The use of these substances will continue to increase in the future as a consequence of the ageing population and other changes in the population demographics, which will, for example, lead to an increasing use of medicine.