Chapter 22 - Wetlands treating contaminated stream water

Abstract

This chapter introduces wetland systems treating contaminated stream water. The aim of this experimental case study was to assess the treatment efficiencies of vertical-flow wetland filters containing macrophytes and granular media of different adsorption capacities. Different concentrations of lead and copper sulfate (constant for one year each) were added to urban stream inflow water to simulate pretreated (pH adjustment assumed) mine wastewater. No breakthrough of metals was recorded. Lead and copper accumulated in the biomass of the litter zone and rhizomes of the macrophytes. The use of macrophytes and adsorption media does not significantly enhance the removal of lead and copper. Particulate lead is removed by filtration processes, including straining. Furthermore, some expensive and time-consuming water quality variables can be predicted with less expensive ones such as temperature to reduce the sampling costs. After studying this chapter, readers should appreciate wetland technology used to treat watercourses contaminated by heavy metals.