Drinking water treatment technologies in Europe: state of the art – challenges – research needs

Eureau is the European Federation of National Associations of Water and Wastewater Services. At the request of Eureau Commission 1, dealing with drinking water, a survey was produced focusing on raw drinking water sources and drinking water treatment technologies applied in Europe. Raw water sources concerned groundwater, surface water, surface water with artificial recharge and river bank filtration. Treatment schemes concerned no treatment, conventional treatment, advanced treatment and conventional plus advanced treatment. The response covered 73% of the population to which drinking water is supplied by the utilities joint in Eureau. Groundwater and surface water are the major raw water sources (>90%). In total, 59% of the drinking water supply concerns not-treated drinking water or drinking water treated with only conventional technologies, while 12% of the drinking water is not disinfected. Challenges for the European drinking water sector are the contamination of raw water sources with emerging substances, absence of disinfection and the potential formation of disinfection by-products. These challenges entail research needs such as the development of quantitative structure activity relationships (QSARs) to better understand and predict the removal rates of treatment technologies for emerging contaminants, the introduction of Water Safety Plans to safeguard the hygienic quality of drinking water, and the optimization of disinfection processes and strategies.