Department Surface Waters - Research and Management

News Portal

Lake mixing – the might of the microorganism

Collection of water samples from Lake Cadagno (canton of Ticino, 1920 m asl). (Photo: Eawag, Helmut Bürgmann)

October 5, 2017
Single-celled bacteria are capable of mixing water layers in lakes – not directly, by movement of their flagella, but by accumulating locally and thus increasing water density. The heavier water then sinks, creating circular currents. Researchers have now observed this process for the first time not just in the laboratory, but in a natural water body – Lake Cadagno (canton of Ticino). Read more


Lake Geneva plummets to 8 degrees from 23

Surface temperatures in Lake Geneva on 1.7.2017: while in Geneva and on the southwest shore near Nyon, temperatures below 10 degrees were recorded, in Évian swimmers were enjoying 22 to 23-degree waters. (Source:

July 13, 2017
If the wind blows away the warm surface waters of a lake, cold water flows in from the depths. As a result of this effect the temperature in Lake Geneva recently sank to 8 degrees. A project led by Eawag and EPFL had predicted this cooling event. Read more


Dr. Damien BouffardTel. +41 58 765 2273Send Mail

Newly discovered methane consumers in lakes

June 7, 2017
In freshwater lakes, large amounts of the greenhouse gas methane are oxidized by bacteria before it can be emitted into the atmosphere. A study in Lakes Rotsee and Zug has now shown that the bulk of this work is done, not by “classical” methane consumers, but by filamentous bacteria previously known only as contaminants of water supplies. Read more


Dr. Carsten SchubertTel. +41 58 765 2195Send Mail

Ecosystem stress caused by micropollutants

June 1, 2017
Micropollutants enter rivers and streams in effluents discharged from wastewater treatment plants (WWTPs). As well as having adverse impacts on individual species, these substances appear to alter aquatic ecosystem functions, such as litter decomposition. This was shown by a research project launched by Eawag in view of the planned upgrade of selected Swiss WWTPs to reduce micropollutant loads. The effects of the first upgrades are already evident. The Microbial Ecology group of SURF participated in the study with the question of whether the frequency of antibiotic resistance is influenced by the treated wastewater. Read more


Dr. Helmut BürgmannMicrobial EcologyTel. +41 58 765 2165Send Mail

Porewater salinity reveals past lake-level changes in Lake Van, the Earth’s largest soda lake

March 24, 2017
This publication in Scientific Reports shows a new way to reconstruct ancient climate events from lake sediment cores. The variability of lake-levels over past millennia is an important source of climate information because it informs us about the ratio between precipitation and evaporation and hence temperature and humidity. The authors show that a very simple method can accurately determine ancient lake level changes: measuring the salinity in the pore water of sediment cores, i.e., the salt content in water that has accumulated in the pore space during sedimentation. Using this tool they reconstructed the considerable changes of the water level of Lake Van over the last 600.000 years. Read more


Dr. Yama TomonagaTel. +41 58 765 5365Send Mail
Dr. Carsten SchubertTel. +41 58 765 2195Send Mail

Fostering knowledge exchange around sensors

March 17, 2017
The "sensors@eawag" working group organized the second workshop to foster knowledge exchange around sensors, loggers, wireless communication technologies and  electronics. The goal was to exchange information between the departments and open discussion about current, new or future applications.  20 interested scientists and technicians attended the meeting initiated by Bernhard Wehrli, which was held in Kastanienbaum for the first time. Read more


Christian DinkelTel. +41 58 765 2151Send Mail

Good arguments for thermal use of surface waters in Switzerland

March 16, 2017
Switzerland’s surface waters contain vast amounts of thermal energy which could be used for heating or cooling. Based on numerous studies, Eawag scientists have now estimated the ecological impacts of thermal use.  Read more


Adrien GaudardScientific collaboratorTel. +41 58 765 5049Send Mail

Breath-taking moments in the Black Sea

February 10, 2017
Periodic oscillations of bottom-water oxygen concentrations can alter benthic communities and carbon storage for decades, reveals a new study published in Science Advances. This is particularly relevant as low oxygen conditions are on the rise in the world’s oceans. Read more


Dr. Carsten SchubertTel. +41 58 765 2195Send Mail

ETH Medal awarded to Kirsten Oswald

January 21, 2017
Kirsten Oswald received an ETH medal for her excellent doctoral dissertation. The medal has been presented at the graduation ceremony on January 20, 2017. Read more