Switzerland: Upgrade Program for Waste Water Treatment Plants

According to analysis, micro-pollutants from treated waste water affect the function of river ecosystems.

In Switzerland, more than 30,000 different substances are used on a daily basis in innumerable products – pharmaceuticals, cosmetics, cleaning agents or industrial chemicals. Many of these substances find their way – via waste water treatment plants (WWTPs) – into surface waters, where they have adverse impacts on aquatic organisms and drinking water resources. To remove micro-pollutants from wastewater, around a hundred strategic selected WWTPs in Switzerland are to be upgraded in the coming years with an additional treatment step.

The upgrade program is being closely followed by scientists at Eawag (Swiss Federal Institute of Aquatic Science and Technology) and the Eawag-EPFL Ecotox Centre. “This provides a unique opportunity to study, more or less in real time, how aquatic ecosystems respond to a reduction in micro-pollutants,” the institute published.

In the initial phase, the scientists investigated the current chemical and biological status, prior to WWTP upgrades. According to analyses, numerous micro-pollutants enter rivers in treated wastewater. The scientists had found an increase in medicines and household chemicals. As reported, organisms downstream of WWTPs showed various symptoms of stress exerted by micro-pollutants.

www.eawag.ch

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