Efficiency of heavy metals removal during roof runoff infiltration through vegetated soil

Stormwater discharged from urban areas can contain significant amounts of heavy metals, especially zinc and copper. Roof runoff is very often directed into the soil and may pose a risk for groundwater quality. Lysimeter research has shown that zinc and copper contained in stormwater may be effectively removed by passing through vegetated soil. The average removal efficiency was greater than 90% and did not depend on the metal concentration in the influent, and the concentrations in the effluent met the limits for drinking water. Infiltration may be a reliable treatment method for roof runoff and may make stormwater safe for groundwater recharge.