How climate change affects Swiss waters
Climate change will also affect waterbodies and aquatic ecosystems in Switzerland. The extent to which this will be the case has now been outlined by Eawag researchers in a synthesis report commissioned by FOEN. Overall, it will be possible to maintain high water quality in Switzerland in the future through management and adaptation.
Only targeted management could control the impact of climate change on our drinking water. However, higher costs must be expected, write the authors of the study "Climate change and freshwater ecosystems. Impacts on water quality and ecological status".
For example, better nutrient management in watersheds can partially offset critical impacts on lakes, such as reduced oxygen concentrations in deeper layers or cyanobacterial blooms in late summer.
Rising water temperatures?
Similarly, pollution peaks, such as overflows from wastewater treatment plants during flood events or pesticides in agricultural watersheds, can be prevented by reducing inputs and improving wastewater and effluent management. However, some changes in water quality, such as rising water temperatures or seasonal shifts in river flow regimes, cannot be prevented even through management.
In addition, many impacts of climate change on water bodies will be indirect, for example, through changes in land use patterns, which will then affect water quality.
Compared to effects on water quality, changes in aquatic ecology are more likely to occur and less likely to be mitigated. These include, for example, the spread of invasive species and species adapted to warm temperatures, a shift of habitats to higher elevations, and increased fish mortality from heat waves.
The study by Benateau, S.; Gaudard, A.; Stamm, C.; Altermatt, F. Originated 2019 on behalf of the Swiss Federal Office for the Environment within the NCCS thematic focus.
"Hydrological Basis for Climate Change" (Hydro2020).
