Pilot Study

New Solutions for Lead Corrosion Control

In response to elevated lead levels found at the tap in some customers’ homes Clackamas River Water conducted a benchtop study to examine the ability of traditional corrosion control treatments to lower the amount of lead released from home plumbing components. Test results indicated that the addition of magnesium sulfate reduced lead release by up to 80%, while the traditional corrosion control treatments of pH/alkalinity adjustment or orthophosphate addition either had no impact or in some cases increased the release of lead. Based upon the success achieved during bench testing CRW, working closely with the Oregon Health Authority, implemented a temporary full-scale magnesium sulfate feed system in the South Service Area. The overall goal of this Pilot Study is to determine the effectiveness of adding magnesium sulfate to the drinking water in the distribution system to reduce lead corrosion at the customers’ tap.

Magnesium and sulfate are two important electrolytes for optimal human health, and play a critical role in almost every metabolic reaction in the body. Magnesium sulfate is a common ingredient in daily multivitamins, rehydrating sports drinks, and rehydrating intravenous solutions, and poses no known health risk if added to the finished water at the concentrations proposed in this document. In fact, magnesium sulfate is added to the bottled water Dasani to improve taste!

Special thanks to all of our customers who participated in the study! The study will be completed in winter 2013.