Evaluation of particle removal at water treatment plants in Nova Scotia

Abstract

The physical removal of colloidal particles, microorganisms and other particulate material is an important objective for drinking water utilities. Because of the low concentration of suspended material in drinking water, turbidity has traditionally been the main water quality parameter for assessing particle removal in water treatment. However, particle counting is becoming increasingly popular for process optimization in conventional plants and for monitoring membrane integrity in new microfiltration and/or ultrafiltration plants. The research describes a survey of particle removal at four water treatment plants in Nova Scotia. Turbidity and particle counts were analyzed in both raw and filtered water. The treatment processes of the four plants was compared using particle count data. The results indicate that particle counters are able to detect decreases in filter performance earlier than turbidimeters.