Abstract

The Canadian Water and Wastewater Association (CWWA), in a study to assess the status of municipal water distribution system, reported that $12.5 billion would have to be invested over 15-year (1997--2012) period to replace the existing deteriorated water mains and construct new mains to cope with the projected population growth. Consequently, Canadian municipalities face a great challenge of managing these replacement and new installation projects efficiently. One of these challenges is how to assess the condition rating of buried water mains. This is because water mains are typically underground, operated under pressure, and usually inaccessible. Condition rating is a mandatory process to establish and employ management strategies for an asset. To assess the condition of water mains, current research considers physical, environmental, and operational factors and their effect on different types of mains (i.e. Cast Iron, Ductile Iron, and Asbestos). A condition rating scale and its associated rehabilitation actions are proposed. This scale is divided into 6 categories, which numerically range from "0" to "10" and linguistically from "critical" to "Excellent"