Abstract
As suspended solids may cause deterioration of water quality, it is important to obtain knowledge about the behaviors of these contaminants in water distribution pipes. This study analyzed the concentrations and characteristics of suspended solids and bacteria in mortar lined pipes of a water distribution system in japan. Mortar lined pipes are a common feature of such distribution systems. It was reported that the amount of bacteria and suspended solids demonstrate similar behavior to one another. Principal component analysis on the basis of concentrations of suspended elements indicated that the presence of mortar may have had an effect on the suspended solids in the pipes, i.e., the primary component was a factor showing a strong relationship with Al and Ca. In other words, particles containing Al and Ca that were likely derived from mortar used to line the pipes were mixed into the water and thus influenced the suspended solids composition. Although the numbers of bacteria estimated from quinone content exceeded the values in water quality standard for drinking water as discussed in our previous paper, living bacteria were few detected at all sampling sites in this study. This indicates that the bacteria in this study were dead or viable but non-culturable.
