Drinking water at the tap: Impact of plumbing materials on water quality

Copper and galvanized steel plumbing systems in houses contribute to trace metal concentrations in drinking water. Levels of lead, zinc, copper, iron and manganese in tap water at various locations in Regina, Canada were monitored and the effect of various factors such as building height, type of building, plumbing age and type of plumbing and water chemistry on trace metal levels was examined. It was found that there was no significant effect of plumbing age or type on the extent of metal leaching in South Regina. In North Regina, plumbing type had a marked effect on the lead and iron levels in drinking water. Lead levels in some individual residences were high; these were probably local effects. It was found that corrosion of solders did not contribute significantly to metal levels. Metal leaching into standing water was found to be mostly from kitchen faucets.