A closer look into the water quality challenge facing the Port of Rotterdam
New research by Deltares shows that thirteen substances with a potential industrial origin are classified as critical or potentially critical for water quality in the Port of Rotterdam under the current Kaderrichtlijn Water (Water Framework Directive). The findings provide a clearer picture of the challenge facing port-based industry. A logical next step is to determine the relative contribution of industry compared with other sources.
By the end of 2027, surface waters in the Port of Rotterdam must comply with the requirements of the Kaderrichtlijn Water (KRW), in English the European Water Framework Directive. New research by Deltares, commissioned by SmartPort, Deltalinqs and the Port of Rotterdam Authority, shows that thirteen of the 122 substances designated under the KRW as either priority substances (45) or specific pollutants (77) and with a potential industrial source are critical or potentially critical for the Rotterdam port area under current KRW standards.
The findings provide a more focused picture of the challenge facing industry in the Port of Rotterdam. A potential follow-up step is to assess the relative contribution of the port’s industrial activities compared with other sources.
Challenge for the Port of Rotterdam
Meeting the requirements of the European KRW, which the Netherlands must comply with by 2027, represents a major challenge for the Port of Rotterdam. As in many other parts of the Netherlands, the water quality of the Nieuwe Maas and Nieuwe Waterweg currently does not meet all environmental standards. At the same time, there is still limited understanding of the role that different sources and activities within the port area play in exceeding those standards. To support a targeted approach for the port area, SmartPort has been conducting research for several years in collaboration with Deltalinqs and the Port of Rotterdam Authority.
CHEMtrend database
This year, Deltares carried out an analysis of publicly available data to gain a better understanding of which substances are most critical for the Rotterdam port area. The analysis followed a recommendation from an earlier study conducted by Deltares and KWR in 2025 on the implications of the KWR for the Port of Rotterdam and its industries.
The study used the CHEMtrend database, which provides insight into trends in chemical water quality. Researchers assessed how individual substances relate to KRW standards, whether concentrations are increasing or decreasing, and whether a potential industrial source could be identified. The results show that thirteen substances with a potential industrial source are critical or potentially critical for the Rotterdam port area. A substance is considered critical when concentrations in the surface waters of the Nieuwe Maas or Nieuwe Waterweg exceed either current or future environmental standards.
Better understanding of important sources
The researchers conclude that a broader shared understanding of the main sources is needed for substances that are critical or potentially critical in relation to the 2027 or 2033 targets. Such insight is essential for identifying the measures that are likely to be most effective in improving water quality in the Port of Rotterdam. For substances that are newly added to the KRW, as well as those that may become critical by 2039, continued monitoring of trends will be necessary.
Next step
The contribution of industrial activities in the Port of Rotterdam relative to upstream sources and other sectors has not yet been investigated. A logical next step would be to identify the main sources, both within the port area and upstream, for substances that are critical or potentially critical and that must meet regulatory standards by 2027 or 2033.
This would help provide a clearer perspective on the actions available to industry in the Port of Rotterdam. The study brings together existing knowledge, identifies key bottlenecks and highlights possible pathways for action. It also underlines the importance of collaboration between businesses, public authorities and knowledge institutes in achieving further improvements in water quality.
