Chemometric analysis for river water quality assessment at the intake of drinking water treatment plants

Abstract

Most of the Mediterranean rivers are suffering the effects of industrial, urban and mining discharges, as well as a reduction in water quantity and quality. Additionally, due to the Mediterranean climate, the natural water resource availability is periodically lower than the water demand in the area. Operation of drinking water plants in these geographical areas needs advanced process control systems where real-time and in-line water quality monitoring tools are key components. Data sets with parameters generated by monitoring sensors and from laboratory analysis are used to reveal the main factors that characterize water quality. Chemometric tools like Principal Component Analysis (PCA) can be used to explore and analyze correlations among different physicochemical and microbiological parameters with the aim to assess the river water quality at the water intake of drinking water treatment plants (DWTPs). Strong seasonal trends in the organic and inorganic matter contents and unusual events in the raw river water quality at the DWTP water intake are revealed. Organic and inorganic patterns are then associated with climatological, meteorological and industrial pollution circumstances typical for the geographical region under study. In addition, microbiological events can be detected at the water intake of DWTP which may occur simultaneously with increasing water contents of organic matter, especially at the beginning of rainfall episodes. The application of PCA on sensors data in the water intake at DWTPs offers new possibilities for improved quality assurance and control procedures for DWTP management and its strategy.