Water pipe maintenance: repairing or renewing?

Abstract

In France, most of the renewal decision are taken with regard to the failure rate and in relation with road works. There is no long term planning. The paper presents an optimisation model helping the choice between renewing or repairing and incurring the risk of future failures. It provides the economically optimal renewal time for each pipe and the expected renewal budget on several years: it is the first step for working out a planning decision tool. In the evaluating of renewal and repairing costs (direct and social costs), the model RENCANA 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.