What needs to be done in the water supply sector to ensure public drinking water supply in vulnerable low mountain regions even under changed climatic conditions? TZW is considering this question as part of a research project within the climate change and model-based adaptation campaign (KLIMOPASS).
The drinking water supply structures of 20 communities in the Black Forest/Swabian Alb region were surveyed and a supply and demand analysis was carried out. This served as the basis to develop a generally applicable methodology (simple structural concept) to formulate measures to adapt water supply to climate change in the individual communities.
According to calculations on the climate-related change in leachate formation, a relatively constant demand, or slightly decreasing at most is assumed for sources with a large catchment area (Qmin > 20 % of Qaverage). Conversely, a significantly lower minimum fill must be calculated in the high-consumption summer weeks for smaller spring tapping (decline in minimum fill in some cases > 50 %).
Nevertheless, a shortage in supply is expected in just a few cases in the study area. This is attributed to the fact that many suppliers have already constructed wells and/or created networks as a result of previous water shortages. All water suppliers solely relying on local spring water should investigate similar measures.
Spring waters are generally highly susceptible to systematic contamination. In future it is anticipated that further treatment measures will be required to remove particles in more than 70 % of the systems in the project region to compensate for climate-induced changes to the raw water quality. In terms of extended power failures as a result of extreme weather, measures to increase resilience are also becoming more important, for example purchasing emergency power generators.
In preparation: EWP Konsequenzen des Klimawandels für Quellwasserversorgungen [Consequences of climate change for spring water supplies]