Risk and performance oriented sewer inspection prioritization

In Austria the global financial crisis of the last decade led to major financial problems in the municipalities. The more the municipalities face such difficulties the more it is essential to provide infrastructure operation and maintenance prioritization methods which focus on risks to the public and the environment. A risk assessment methodology, a definition of relevant hazards causing "undesired events" responsible for deficits regarding functional requirements and the use of a bivariate logistic regression analysis to derive the main influencing factors on the occurrence of these hazards is presented in this paper. Further a vulnerability analysis which is used to quantify hydraulic driven consequences of undesired events is described. The methods were applied to one part of an Austrian sewer system and for 2 functional requirements. The results of the analyses are presented according to the hazard "sewer collapse".