Effect of distribution systems materials on bacterial regrowth

Abstract

Distribution system materials may be among the most important factors influencing the growth of biofilms in distribution systems. However, relatively little research has been done to demonstrate the relationships between pipe materials and linings in the presence of varied organic carbon levels and disinfectants on biofilm growth and subsequent microbial water quality. Research in this area is of increasing importance to water utilities as aging sections of distribution systems must be repaired or replaced and networks must be expanded to meet a growing consumer base. For utilities seeking methods to control distribution system biofilm, two alternatives are available. These include the reduction in organic carbon and/or the replacement/relining of iron pipe in their distribution systems. If organic carbon is high, pipe replacement or relining may be a good option for reducing biofilm problems. However, the economics of this choice must be weighed against treatment changes leading to the reduction in organic carbon.