Water Quality Changes Associated with New & Standard Domestic Distribution System Piping Materials

The distribution system, including home plumbing materials, has been identified as a major contributor to deteriorated water quality and also taste and odor (T&O) issues in drinking water (Khiari et al., 2004, Hem et al., 2002, Dietrich et al., 2004, Durand et al., 2004). In evaluating the distribution system, work has focused mainly on materials that water contacts before it enters the consumer’s home drinking water infrastructure, such as water mains, service pipes, and storage tanks (Rigal et al., 1999 and Tomboulian et al., 2004). The sustainability of materials for home plumbing systems, as they relate to T&O properties, has not been widely explored. The growing need for more detailed studies of common household plumbing materials is evident, based on limited data. Studies have shown that many T&O episodes result after installation of new ma-terials (Khiari et al., 1999). A lack of understanding of the possibility that these materials may contribute odor could result in dissatisfied consumers or unnecessary panic in a community. T&O problems in the distribution system and domestic plumbing infrastructure are caused by biological sources (fungi and bacteria), chemical sources, system design (dead ends), and system operation (blending chloraminated water with chlorinated). T&O problems are becoming more prevalent as utilities and homeowners use newer polymer materials for piping and as chloramines replace chlorine for residual disinfection (Seidel et al., 2005). In order for utilities to advise on and deal with T&O issues, they must understand problems in both the public distribution systems and in domestic plumbing infrastructure. Aesthetic qualities of drinking water reaching the consumer’s tap can be significantly affected by the type of materials and disinfectant used in the domestic plumbing system (Rigal et al., 1999; Khiari et al., 1999). Studies have shown that the presence of residual chlorine can have deleterious effects on some pipe materials and subsequently affect the T&O properties of drinking water (Marchesan et al., 2004). As more utilities convert to chloramines, there is a need to further evaluate interactions of piping materials and chloramines (Seidel et al., 2005). Studies have shown that rubber gaskets deteriorate in the presence of chloramines, generating undesirable odors Water Quality Changes Associated with New & Standard Domestic Distribution System Piping Materials