A methodology to estimate losses in level of service for urban infrastructure networks

Interventions on infrastructure networks in cities cause disruptions to the service provided by the network that requires the intervention. They also cause disruptions to the service provided by other networks that have to be at least partially shut down so that the intervention can be executed. Due to these effects, there is substantial benefit to be obtained by grouping interventions on all networks that are spatially close to one another, i.e. intervention programs for spatially close networks should be developed together. This benefit is principally due to reduced interruption to services and reduced costs of intervention. The challenge of determining such combined intervention programs is, that it is difficult to quantify the value of lost service, which depends on how different stakeholders value the services as well as how long and in which way the services are interrupted. This paper presents a methodology to estimate the loss of service on five infrastructure networks due the deterioration and due to the execution of both preventive and corrective interventions, and a way to formulate an optimisation equation in order to construct an optimal combined intervention program. The advantages and disadvantages as well as next steps in the research are discussed.