AWWA INF52149

In France, most of the water main renewal decisions are made with regard to the failure rate and in relation to road works. There is no long term planning involved. This paper presents an optimization model the can assist in making the choice between renewing or repairing water mains and incurring the risk of future failures. The model provides the economically optimal renewal time for each pipe and the expected renewal budget for several years; it is the first step for working out a planning decision tool. In the evaluation of renewal and repair costs (both direct and social costs), the model takes into account the pipe's failure evolution, the characteristics and the local environment of the pipe, the sensitivity of the consumers facing a water delivery interruption and the hydraulic position of the pipe. It is an approach which takes into account technical, social and economic elements Includes 10 references, tables, figures.