EPFL launches joint project to assess the condition of Lake Geneva – rts.ch

Of the approximately 500 volunteers sought within the Lémanscope project, almost 270 have already been found, you can read on the dedicated website. The program, led by the École Polytechnique de Lausanne (EPFL), is carried out in collaboration with the Swiss Federal Institute of Aquatic Science and Technology (Eawag), the University of Lausanne (UNIL) and the Association for the Conservation of Lake Geneva (ASL).

Lemanskop It starts with a simple observation: Faced with threats that are difficult to predict and data incomplete, scientists are finding it difficult to make a formal diagnosis about the health of Western Europe’s largest body of water. Climate change, pollution, invasive species like the quagga mussel are all elements that can harm water quality.

Lack of complete mixing of the lake can also be a problem. This phenomenon, which usually occurs naturally but has not been observed for 12 years, allows deep and surface waters to mix and thus distribute oxygen and nutrients.

>> Read also: Lake Geneva’s water temperature is breaking records and threatening its ecosystem

Data for the report in the application

Faced with this uncertainty, scientists are looking for guidelines. According to them, measuring water clarity and color provides valuable information about the condition of the reservoir. This is where volunteers come to the rescue: after registering, they receive a scientific instrument called a Secchi disk, which they must lower to the bottom of the water until they can no longer see it. They then report the measured data in an app that is downloaded to the mobile phone.

Measurements taken by volunteers are then transmitted to scientists and compared with satellite data. Ultimately, they contribute to a better understanding of the health of Lake Geneva, emphasizes EPFL.

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