Biological treatment processes in wastewater stabilization ponds (WSPs) are strongly influenced by climatic conditions. There is limited information about the removal of human pathogens in Artie WSPs, which experience an extreme environment and short treatment seasons. Relevant to public health, this paper investigates the removal of human pathogenic microorganisms in the lagoons during the treatment season and in the final effluent being discharged into the environment in the remote community of Clyde River (NU). Wastewater samples were obtained from trucks, the two-celled WSP system, and final effluent/decant samples between September 2012 and September 2013. The quality of the wastewater was characterized for CBOD_5, ammonia (un-ionized), pH, dissolved oxygen, total suspended solids and Escherichia colilcoliform bacteria. The presence/ absence of bacterial pathogens (Listeria monocytogenes, E. coli O157:H7, Campylobacter spp. and Salmonella spp.) was determined using Q-PCR protocols following enrichment. Both WSPs were anaerobic throughout the 2012 and 2013 treatment seasons. There were no indications of algae blooms and pH remained constant at ～7.5. Consequently, reductions in TSS, CBOD_5, and E. colilcoliform bacteria levels were minimal. L. monocytogenes and E. coli O157:H7 were found in the samples collected from both of the WSP cells throughout the 2013 treatment season. Inconsistent use of the two-cell WSP system may have affected the treatment performance. In conclusion, the results obtained in this study indicate that the current operation and design of the WSPs in Clyde River may not be able to effectively remove human bacterial pathogens.
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