Stormwater treatment: do constructed wetlands yield improved pollutant management performance over a detention pond system?

Constructed wetland systems have been proposed as representing an improved ecotechnological option over detention basins, in terms of their abilities to reduce stormwater bacterial and nutrient loads to receiving waters. Concentrations of microbial and pollutants were determined in inflow and outflow samples collected from each type of system. Removal efficiencies for the wetland although higher than for the pond, were lower than some previously reported values for the treatment of municipal wastewater by constructed wetlands. Performance of a number of constructed wetland systems for stormwater treatment is evaluated considering the functional components of the systems.