New technology at Winterswijk sewage treatment plant

Water Board Rijn and IJssel is expanding the sewage treatment plant in Winterswijk. Thanks to a new technique they can make the wastewater even cleaner. This technique also removes medicine residues, ammonium and phosphate. The cleaned water goes to the Groenlose Slinge. As a result, the stream does not fall dry in the summer and the water in the stream becomes cleaner.

The new technique is a combination of ozone and aerated activated carbon filtration. This extra "step" takes place at the end of the existing treatment process. It is done by first treating the water with ozone. Then the water is filtered with activated carbon in eight large tanks. As a result, drug residues, ammonium and phosphorus are better removed. Thus, the purified water becomes even much cleaner and thus also the streams and rivers where this purified water goes.

Work

New tanks were installed this week. The work is expected to be completed in early 2025. To develop the water treatment plant, the water board is working with Aan de Stegge, Pannenkoek GWW, Nijhuis Saur Industries, Moekotte and Witteveen and Bos. They are working together in the Local Circular Water Combination.

In addition, the water board is designing a natural post-purification system. Plants and soil have a natural purifying effect in the surface water, allowing them to remove the last ammonium residues and restore enough oxygen to the water. The natural post-purification is located next to the water treatment site.

More actions for clean water around Winterswijk

The concentration of drug residues in the water of the streams around Winterswijk is higher than in other places. The effects on aquatic life are also greater. This emerged from research by the water board. The water board therefore not only adjusts the purification in Winterswijk, but also takes action with other organizations. For example, the Streekziekenhuis Koningin Beatrix (SKB) will issue urine bags starting June 3, 2024. Patients undergoing a CT scan with contrast medium will be offered four pee bags. By collecting the pee, no contrast fluid ends up in the sewage, and therefore not in nature. Contract liquids do not belong in nature and are not biodegradable. They also cannot be removed from sewage using normal treatment techniques.

Currently, the water board removes about half of the drug residues from wastewater. With improved treatment and puddle bags, they can remove 70 to 80 percent of the drug residues.

'Smart pumping stations'

Water treatment works best with the most constant supply of wastewater. To achieve this, the water board is working with the municipality of Winterswijk to improve water transport with "smart pumping stations. The technology of these pumping stations ensures that, if necessary, the water is buffered in the municipal sewer and gradually pumped to the water treatment plant.

With the improvements to the Winterswijk water treatment plant, the water board and partners are contributing to the Water Framework Directive (WFD). The WFD sets out European goals for clean water.

Residents and businesses also have a role

Water Board Director Dennis Wolsink is pleased with the expansion of the Winterswijk water treatment plant: "We have made a nice step with this improvement. What doesn't end up in the water, we don't have to take out. We as residents can also contribute to this. With the Streekziekenhuis Koningin Beatrix, for example, we distribute urine bags. With these we prevent contrast agents from ending up in our purification system. We also work together with pharmacies to encourage people to return leftover medication and not flush it down the toilet."