Drinking water treatment technologies in Europe: State of the art - vulnerabilities - 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 made 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 nottreated drinking water or drinking water treated with only conventional technologies, while 12% of the drinking water is not disinfected. Vulnerabilities of the European drinking water supply are the contamination of raw water sources with emerging substances, the absence of disinfection and the potential formation of disinfection by-products. Based on this, research needs are 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 prevent hygienic contamination of drinking water, and the optimization of disinfection processes and strategies.Water ManagementCivil Engineering and Geoscience

Transformation of organic micropollutants during river bank filtration: Laboratory versus field data

This paper investigates the degradation behavior of 14 organic micropoliutants (OMPs), selected for their different physico-chemical properties (e.g., molecular weight, hydrophobicity and charge). In soil columns simulating the conditions prevailing in the first meter of river bank filtration (RBF) media. The results from the column system are compared to RBF field data obtained from the Vitens drinking water company in The Netherlands. The study explores the role of sorption media (sand filled columns and polyethylene tubes) as carrier material for the biomass. Polyethylene tubes with the same specific surface area as sand in the columns, were operated under similar conditions to compare OMP removal in the two systems. Both the column and field data indicate that negatively charged OMPs with Log D ranging from 0.65 to 1.95, positively charged OMPs with Log D ranging from -0.59 t o 0.21 and neutral OMPs with Log D (-1.9 t o 1.12) were more susceptible to biodegradation. The compounds that persisted (carbamazepine, atrazine, phenytoin, lincomycin) were positively charged with lower Log D (-1.33) or neutral with higher Log D (1.56 t o 2.64). Hydrochlorothiazide showed poor biodegradabiiity despite being neutral and having a lower log D (-0.71); it is an exception to the above behavior for reasons that have not yet been identified. A comparison of OMP removal in a biologically active polyethylene tube with a biologically active column showed that the biomass established in either systems removed the same OMPs and to similar extent for a majority of the OMPs. This finding supports the use of polyethylene tubes as a simple, cheap and quick method for investigating the trends in OMP removal in RBF.Water ManagementCivil Engineering and Geoscience