At least 60% of First Nation communities in Manitoba, including the Lake Manitoba First Nation, are in wetland areas.47% of First Nations communities in Manitoba served by facultative lagoons failed to achieve the total phosphorus (TP) concentration of 1 mg/L in proposed regulations for effluent discharge into the environment. The Lake Manitoba First Nation community facultative lagoon system treats domestic wastewater and seasonally discharges effluent into a wetland that connects to Lake Manitoba. This research was performed to estimate phosphorus removal efficiency through the natural wetland during the vegetation growing season.The average TP concentration reduction utilizing the natural treatment area of 1.3 ha was more than 70%, achieving the desired total phosphorus below 1 mg/L.These short-term study results indicate the potential of natural wetland treatment applications under cold continental climate conditions, as an effluent polishing step to satisfy regulatory requirements for phosphorus reduction in smaller First Nations communities.