Submitted to: Meeting Abstract
Publication Type: Abstract only
Publication Acceptance Date: 2/9/2011
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: This study evaluated chemical and microbial water quality changes in two reclaimed waters as a function of residence time within distribution systems or storage time in tanks. Here we report the microbial water quality changes with particular focus on the incidence of waterborne and waterbased pathogens within reclaimed water. The influence of water age or residence time on the water quality of reclaimed water was evaluated in two ways: i) Through the monitoring of reclaimed water within distribution systems with increased distance from two wastewater treatment plants; and ii) Through the evaluation of reclaimed water stored in storage tanks. Such storage frequently occurs in the winter in the SW USA when irrigation needs decrease. Heterotrophic plate counts (HPC) increased with increased residence time in distribution systems. In storage tanks, HPCs initially increased with residence time, but subsequently decreased as assimilable organic carbon concentrations decreased. Waterbased pathogens were periodically detected at significant concentrations in both distribution systems and storage tanks. Waterbased pathogens included Legionella, Mycobacterium, Aeromonas and amoebas. In contrast, waterborne pathogens were not detected at significant concentrations suggesting that waterbased pathogens may be the greater concern in reclaimed water.