Treatment Performance Assessment and Modeling of a Natural Tundra Wetland Receiving Municipal Wastewater

Abstract

The application of natural tundra wetlands for municipal wastewater treatment is an option to meet upcoming federal wastewater systems effluent regulations for Canada’s Far North. A treatment performance assessment with physical, hydraulic and biogeochemical contextual data was conducted on the wetland treatment area of Coral Harbour, Nunavut. A modified Tanks-In-Series model was used to model treatment kinetics. The study showed seasonal variability in treatment performance and hydraulic characteristics. A decrease in vegetation diversity and deposition of organic detritus was observed in high effluent loading areas. Effective reduction in effluent concentrations was observed. Dilution from watershed contributions accounted for much of the reductions observed. The importance of the determination of the hydraulic residence time, field delineation of the wetted area, and delineation of the watershed was demonstrated. First order rate coefficients determined suggested that the selection of the lowest percentiles from literature of southern treatment wetlands is conservative in this case.