Water Research Foundation Project #4618: Status and Application of Cathodic Protection in the Water Utility Industry

Some water utilities have been exploring a variety of techniques to fight external corrosion and to preserve the value of their buried assets however a standardized and defensible approach does not exist. This project will investigate technical and economic considerations to retrofit buried metallic pipelines with CP. The water utility industry is inherently different as compared to oil and gas pipeline industry. The water utility industry is not regulated or required to apply cathodic protection to its pipelines. Application of cathodic protection in the water utility industry is elective and only for the purpose of leak rate reduction and asset preservation. Hot spot and retrofit applications of cathodic protection are typical in the water industry to control leak and break rates. Hot spot cathodic protection is and operations and maintenance driven procedure of installing a galvanic anodes directly connected to metallic pipes at the location of a pipe failure during the pipe repair activities. These anodes are installed without any means of monitoring and stay in the ground until total depletion, usually without replacement. Retrofit CP refers to the practice of systematically protecting existing pipes with galvanic cathodic protection after construction. The on-going water research foundation project (WRF # 4618) included a literature survey, corrosion industry and water industry workshops at major conferences, collection and analysis of utility case studies from U.S. and Canadian utilities, and development of a CP hot spot and retrofit guidance manual to assist water utilities in achieving economic savings and extending asset life. The goal was to produce a utility focused design criteria manual, standard specifications, drawings, and financial template/methodology that will provide a consistent financial benefit measurement of the value of the anode hot spot and retrofit programs. In this paper, a summary of the research and analysis is presented along with supporting case studies.