AWWA ACE61771

This study reports on the increase of lead contamination of water contacting brass or lead bearing plumbing if there is a galvanic connection to copper. The rate at which lead materials were sacrificed by galvanic action was directly influenced by various factors including chloride and sulfate concentrations, type of disinfectant, pH and insulating gaps between the metals. The galvanic current spatially separates the anodic and cathodic reactions, thereby lowering the pH near the surface of the lead materials in poorly buffered waters and increasing lead solubility. Chloramine caused sustained galvanic currents relative to chlorine. The partial replacement of lead service lines by new copper pipes can be expected to increase lead leaching under at least some circumstances. Includes 20 references, figures.