The latest news from Eawag

A new Eawag study provides insights into how prolonged heatwaves can affect the entire aquatic food web.

When are tenants willing to reduce their energy consumption? And what kind of investments are homeowners willing to make to save energy? Researchers from Eawag and WSL are investigating this through surveys. Their aim is to gauge public support for the design of the future energy system.

After an exceptionally early heatwave in May, western Europe recorded its hottest June on record. Immediate protection is essential, but not everyone can access cool housing, shade or flexible working conditions. A new Thermal Justice framework shows how cities can reduce heat risk without shifting its burdens to other people, places or future generations.

When, where and why do different fish species migrate – and how successfully do they manage to do so despite the barriers posed by hydroelectric power stations? Eawag researchers are investigating this by tagging fish and tracking their signals over a period of several years. Initial analyses have yielded surprising results.

The Swiss Research Magazine Horizons has accompanied a team of scientific divers on an expedition to Lake Constance.

Artificial floods can mimic the dynamics of natural rivers and strengthen ecosystems that are restricted by hydroelectric power stations and residual flow sections.

As the summer of 2026 clearly demonstrates, the increasingly frequent and extreme periods of drought also threaten the availability and quality of groundwater, by far Switzerland’s most important source of drinking water. A new factsheet summarises the current understanding of drought in groundwater. To take preventive action, Switzerland should consistently promote the replenishment of groundwater, make infrastructure more resilient and develop a more comprehensive management approach.

Every year, Swiss wastewater treatment plants release around 5 tonnes of microplastics into the environment. That is relatively little: It is estimated that around twice as many microplastic enters Swiss water bodies via the atmosphere. These figures come from the largest nationwide investigation to date on ultrafine plastic particles in the air, water and soil, a joint project by Eawag, Empa and Agroscope. These figures were made possible thanks to a new approach to sampling that yields significantly more reliable results than previous processes.

The energy transition is taking its toll on our bodies of water. The Eawag Info Day, which is taking place today in Lucerne, therefore focuses on the role of water in the energy transition. Christian Stamm, Deputy Director of Eawag, explains where the problems lie and how Eawag is helping to find solutions.

Fair research partnerships require more than funding: trust, shared decision-making and jointly defined priorities are key.

As glaciers retreat, new lakes emerge and ecosystems develop. A study in Greenland shows that they are highly connected to the surrounding landscape.

Pesticides that enter groundwater and eventually drinking water can pose risks to both human health and the environment. Groundwater in karst regions is particularly vulnerable to contamination because the protective soil layer is often very thin. A study using high-frequency sampling shows that groundwater from karst springs in the Jura can become heavily contaminated, especially after rainfall. Up to six percent of drinking water samples from the Swiss Jura could exceed the regulatory limit.

Native freshwater mussels are among the most endangered animal groups in the world. Their populations are also declining in Switzerland. Yet, as natural water filters, they play a vital role in our water bodies. To protect them, we need to study them more closely, but this is difficult as many species are almost impossible to distinguish morphologically. A study by the aquatic research institute Eawag shows that genetic data could provide a valuable basis for this.

Green roofs differ from ground-level habitats in terms of biodiversity. This can help to boost biodiversity in cities.

When there is a prolonged dry spell and local authorities call on residents to save water, questions immediately arise as to whether it would make sense to reuse more water and collect rainwater. In light of recent events, here are some answers from Prof. Kai Udert, Head of the Process Engineering Department at Eawag.

Toxic blue-green algae blooms are a threat to lake ecosystems and can be toxic for humans and animals. At present, it is only possible to predict roughly when and where such blooms will form – based on water temperature and nutrient levels. Now, a long-term study by Eawag researchers shows that the accumulation of blue-green algae in a lake depends crucially on other plankton species: some organisms promote blue-green algae blooms, whilst others can prevent them even under favourable environmental conditions.