Accumulation of heavy metals in stormwater bioretention media: A field study of temporal and spatial variation

Abstract

Short term studies have found that stormwater biofiltration systems, also known as bioretention systems or raingardens, are very effective in reducing heavy metal concentrations. However, their long-term treatment performance, as well as the spatial and temporal accumulation of metals within these systems remain uncertain. This paper reports on a large scale field study that assessed the changes over time of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) levels in biofilters varying in age, design, and catchment characteristics. The survey incorporated 29 biofilters in 2006/7 and 49 biofilters, in 2014/15, located in three major Australian cities (Melbourne, Brisbane, and Sydney). Notin..