Maas river deteriorating due to harmful substances, climate change: water companies

Due to persistent discharges of harmful substances and the effects of climate change, the water quality of the Maas river is deteriorating. The partnership of Dutch and Belgian drinking water companies RIWA-MAAS warned about this. According to the organization, it is important that the river, which provides drinking water for 7 million people, is better protected. Starting with a better overview of where all the harmful substances come from.

“We must stop seeing our surface water as a kind of sewer,” director Maaten van der Ploeg of RIWA-Maas said in the organization’s 2022 report. It discusses, among other things, the inadequate permits of companies that discharge substances into the river. Not all harmful substances measured in the Maas are reflected in companies’ licensing regulations. The drinking water companies would very much like to get a “complete overview” of this.

“As soon as it is clear who discharges what into the Maas and where it is essential to reduce the discharge of harmful substances as quickly as possible,” the report said. The drinking water companies filter the Maas water to supply clean water. Tap water in The Hague, Rotterdam, and Limburg, among others, comes from the Maas.

According to RIWA-Maas, climate change has a significant effect on the river. For example, 2022 was the driest year of this century for the Dutch part of the river. Less water does not only mean that water shortages can occur. It also means that harmful substances are less diluted, the water companies explain.

Last year, 79 substances were measured in concentrations above the European target values. Due to contamination, an intake stop or restriction had to be imposed 62 times at the Dutch and Belgian drinking water companies that use water from the Maas.

The report also mentions “the importance of remaining constantly alert to emerging contaminants.” As an example, the partnership cites PFAS discharges by chemical company Chemours in Dordrecht. The drinking water companies are conducting legal proceedings against Chedmours’ discharge permit. According to the drinking water companies, pollution with agricultural fertilizers, which promote algae growth, and medicine residues are also problems that need to be better addressed.