AWWA JAW55362

Water treatment professionals have long battled corrosion of distribution system pipe materials. Although chemicals that inhibit corrosion are commonly used, they are not always effective. Thus, researchers are always on the lookout for practical corrosion mitigation strategies that do not require the purchase or use of chemicals. For example, aluminosilicates, which often deposit in distribution system plumbing lines, have previously been thought to inhibit corrosion, even though they cause increased head loss, reduced flow, and consumer complaints related to postprecipitation. However, the results of this study suggest that this assumption should be reexamined because aluminosilicates actually worsened some aspects of corrosion. There currently is no hard scientific evidence that such deposits are beneficial to corrosion in circumstances of relevance to water purveyors. With the proliferation of regulations that mandate lower levels of metals, such as lead and copper, in tap water and in the environment, more research into innovative strategies that can help prevent the release of metals is merited. This article takes the first steps to a better understanding of the impact of aluminosilicates on corrosion of copper and lead plumbing materials. Includes 25 references, figures.