Analyzing a Small-Scale, Constructed Wetland for Stormwater Treatment

Stormwater treatment by means of constructed wetlands has the ability to effectively remove pollutants such as total suspended solids, nitrite, nitrate, and ammonia. Utilizing two small, lab-scale constructed wetlands, one free water flow system and one subsurface flow system, our research team analyzed the levels of these pollutants at different locations in the wetland. Our team of two Civil and Environmental Engineering undergraduate students tested a variety of different water samples including tap water, stormwater, and a high nitrate solution. A consistent decrease in nitrate and nitrite was observed throughout the systems. While there was not an overall decrease in ammonia, there were decreases between individual basins. This research demonstrates the potential impact of implementing constructed wetlands as a lower cost, environmentally friendlier alternative to reduce combined sewer overflows, or treatment via traditional wastewater treatment plants.