| Urban stormwater runoff introduces many contaminants into aquatic systems, some of which are harmful to aquatic and human life. Conventional stormwater management practices are designed to drain the city of excess runoff as rapidly as possible to prevent flooding and are not designed to control water quality. Wetlands are effective in improving runoff water quality by various physical, chemical and biological processes. When introduced into a city storm drainage plan one of the major benefits is less contaminated receiving waters. The use of natural wetlands as stormwater treatment facilities is relatively new, therefore, long-term effects are not well known. Monitoring is essential, then, as a tool to document and assess the changes in water quality treatment and wetland integrity.; This study presents an initial assessment of stormwater quality treatment by a natural wetland in Rocky Ridge subdivision, northwest Calgary. The study is based on three years of data collection, the first two of which provide baseline wetland water quality data and the third which provides water quality data associated with the introduction of stormwater into the wetland. Initial analysis of the data indicates that Rocky Ridge wetland is effective in reducing stormwater pollutants. However, further monitoring over several additional years is required to provide sufficient data for a complete assessment of the long-term capability of a natural wetland for stormwater treatment. |
