AWWA WQTC69290

The objective of this research was to assess the effectiveness of a simple pipe loop system and protocol to predict localized corrosion of copper plumbing in distribution systems, and to assess treatment alternatives in a drinking water that has been associated with customer complaints of pinhole leaks. Regular examination of the internal surface of copper pipes positioned in the loop revealed signs of localized corrosion (isolated mounds of corrosion byproducts) after only 72 days. Close examination of pipe sections removed from the loops after 100 days clearly showed that localized corrosion was taking place. Cross-section analysis of the pipe showed pits as deep as 0.75mm that were covered by a thin membrane and mound of blue-green corrosion products. The study showed that simple, inexpensive copper pipe loops can be useful in predicting pitting tendencies of copper piping used for drinking water, as well as to assess the effectiveness of treatment alternatives. Includes 3 references, figures.