Pollution of drinking water transported by corroded metallic pipelines

Abstract

Corrosion of metallic water pipelines is a function of the pipe’s surrounding environment (soil and water). This means that it is important to know the physical and chemical characteristics of the pipe’s surrounding environment. The corrosion of externally unprotected metallic water pipelines, particularly ductile iron pipes, in localities with aggressive soil conditions is becoming a significant problem: repair and replacement costs are high, and failures cause supply interruptions to customers and inconvenience to the public. Anti-corrosive protection for metallic water pipelines, their fittings and accessories is very important, because they may be attacked by corrosion with time. The tendency of a metallic substrate to corrode is a function of the surface characteristics of the metal and of the metal/protective film interface, the physical, electrical and electrochemical properties of the film, and the nature of the environment in which the pipelines system is placed. In this work the authors have looked at the corrosion problems of metallic water pipelines and their control. The corrosive properties of water and soil environments are reviewed. Parameters affecting corrosion are discussed. The pollution of drinking water transported by metallic pipes caused by corrosion is discussed. The purpose of this work is to provide guidelines for materials selection in water and soil environments, and how the water pipelines can be protected against metallic corrosion.