Bacteriological and Physico-Chemical Characterization of Surface Water and Evaluation of a New Water Treatment System in Southwestern Ontario Dairy Farms

The objective of this study was to characterize untreated surface water sources for dairy farms in Southwestern Ontario for their physico-chemical and their bacteriological properties, including isolation and analysis of antimicrobial susceptibility in bacteria. This study also evaluated the efficacy of a newly designed water treatment system. The bacteriological analysis of 15 surface water sources indicated a high level of contamination with a wide variety of Gram-negative bacteria. Although multidrug resistant E. coli strains were isolated, the overall proportion of antimicrobial-resistant bacteria in surface water was low. The physico-chemical parameters of the investigated waters, including turbidity, total solids, hardness, iron, and UV transmittance, were above the acceptable limits for use on the farms. The new water treatment system that was tested effectively reduces bacterial numbers below the detection limit and improves physico-chemical properties of water to acceptable levels after treatment. The present study supports the use of CF and sand filtration prior to decontamination with UV light.