Drinking water from surface and ground water: production costs and influence of the climate change

Drinking water production may be affected by quality of the water source, above all surface water bodies. Efforts are being made to adopt the best strategies in the drinking water treatment plant (DWTP) management under these adverse conditions, with the aims to guarantee potable water and optimizing water production costs. This study refers to the large DWTP of Ferrara, Italy (2.5 10^7 m3/year of water distributed in 2021) which treats surface water (Po River) for around 70 % and alluvial well water for the remaining 30%. It presents the results of an analysis of the annual drinking water production costs and the related items before and during COVID-19 pandemic. A focus is then done on the effects the climate change may cause on the water quality at the source, the resulting management needs, and the final production costs. It emerges that production costs are increased during the years due to the increased costs of energy, chemicals and activated carbon. Water withdrawal is the issue which most affects the final production costs due to the high energy consumption.