Water Quality of Traditional Rainwater Storage Tanks in Southern Morocco – Risk for Consumer Health

Around the world, the problems of water quality remain a major environmental concern. This study aimed to determine the health risk related to water consumption collected and stored in traditional tanks. In total, 26 water samples from traditional water storage tanks (TRST) and 11 sediment samples were collected from 13 sites belonging to four different provinces in the Souss Massa region, Morocco. The water samples were subjected to bacteriological and physicochemical analysis. X-ray diffraction and scanning electron microscope analyses were performed to describe the different mineralogical and chemical properties of sediments. The results show that the bacteriological quality is not satisfactory to the required standards in 92% of the samples analyzed. This non-conformity is justified by the presence of microorganism’s indicators of fecal contamination: Total Coliforms (54%), Intestinal Enterococci (62%), Escherichia coli (31%), and Spores of anaerobic sulfite-reducing microorganisms (46%). The physicochemical analyses carried out on the water sampled show that concentrations below the standards recommended by the World Health Organization (WHO) and the Moroccan standard of the different parameters studied. The Water Quality Index (WQI) calculated for all TRST ranges from 10 to 15, indicating excellent water quality. The analysis of the distribution of minerals in the various sediment samples taken shows the presence of several minerals in varying quantities without risk to human health. Clay minerals with tectosilicate are the most detected in the reservoirs. This study showed that the consumption of water stored in the TRST would be without risk to the health of the rural population if preventive maintenance and control measures were taken to improve their bacteriological quality.