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The recognition of the environmental impacts of untreated wastewater has lead to the investigation of effective and low cost treatment technologies. Constructed wetlands have not been widely adopted in Atlantic Canada and Local issues pertaining to the integration of these systems need to be addressed including their cold climate operation and treatment efficiencies. The objective of this research was to evaluate a subsurface flow wetlands ability to treat multi source waste for Atlantic Canada. A subsurface flow wetland was designed to treat wastewater generated from a dairy farm in Nova Scotia. These wastewaters include: (i) milkhouse washwater from approximately 55 cows, (ii) leachate from four silage silos, (iii) solid manure runoff from a concrete pad, and (iv) domestic sewage from two households. The size of wetland is 8 m x 25 m with the main body being 0.6 m in depth and constructed with the combinations of course and fine gravel. Cattails (Typha sp.) are planted in the center of the wetland. Samples from both the inlet and outlet are taken on a weekly basis from April 2003 through December 2004 and analyzed for Total Kjeldalh Nitrogen, Ammonia Nitrogen, Nitrate Nitrogen, Soluble Reactive Phosphorus, and Total Phosphorus, pH, Total Suspended Solids, Five Day Biological Oxygen Demand, and E. coli. Results showed that the wetland was not capable of reducing high levels of pollutants from the silage leachate and its low pH. After its diversion from the wetland, Biological Oxygen Demand and Phosphorous removal efficiencies increased to moderate levels. However, nitrogen removals showed high variability and low treatment. These findings suggest that constructed wetlands may be limited in there ability to treat nitrogen in wastewater and sizing may need to be reconsidered for cold climate regions.