A practical scheme for building and assessment of water pipe renewal policies

Asset management is nowadays a concept that is widely recommended to manage the condition and performance level of water distribution networks. It's clearly established that the implentation of an asset managment approah is usefull. But many challenges still unsolved especially concerning the implementation and the assessment of this type of approaches. This paper adresses major theoretical and practical issues of building of replacement policies for water pipes by considering some original criteria and indicators. The construction of policies is based on prioritization schemes dealing with multi-criteria aggregating methods. The classification of pipes candidates for renewal is ensured by comparing two kinds of aggregating methods: i) an unsophisticated approach by using adapted weighted sum methods; and ii) a sophisticated approach by using outranking methods. The underlying reason for comparing these methods is to know whether the unsophisticated methods ensure reliable renewal policy compared to the sophisticated one. The other issue concerns the development of specific indicators to assess renewal policies. One of them deals with an interesting concept of functional value, which is rarely treated in literature and represents an original way to measure the role and the function at the pipe scale and at the network scale.