Sensible sewer system rehabilitation using information on sewer system settlement Utilisation des informations sur les tassements différentiels des systèmes d'assainissement pour la définition des programmes de réhabilitation

If all parameters influencing sewer performance were known (or deterministic) then the decision making process associated to the planning of sewer replacement should be relatively straightforward. However, when trying to forecast service life, uncertainties arise considering the deterioration process, the variability of sewer pipe properties, environmental conditions or the used information resources (mainly in-sewer inspections). Consequently the management of sewer networks is based on uncertain and incomplete information. Because in areas with significant ground settlement the majority of dysfunctions (blockages, infiltration, sand silting, decrease in hydraulic capacity etc.) will probably be caused by differential settlements of sewer pipes a research into this topic was initiated.