Risk Assessment of Water Treatment Plants Using Fuzzy Fault Tree Analysis (Case Study: Jalaliyeh Water Treatment Plant)

Document Type : Research Paper


1 Prof., Center of Excellence on Engineeing and Management of Civil Infrastructure, School of Civil Engineering, College of Engineering, University of Tehran, Tehran, Iran

2 Assist. Prof., Department of Irrigation and Drianage Engineering, Aburaihan Campus, University of Tehran, Tehran, Iran

3 MSc of Civil-Environmental Enginering, School of Civil Engineering of Engineering, University of Tehran, Tehran


In this research, Fault Tree Analysis (FTA) with fuzzy and crisp approaches were used to assess the risk associated with the performance of water treatment plants. The fuzzy logic was used to consider the uncertainties in expert opinions and the nature of threats. This modelling approach was implemented as a case study in Jalaliyeh water treatment plant in Tehran. One undesirable event in such structure was improper water quantity and quality. The results of this case study showed that probability of treatment plant failure under fuzzy and non-fuzzy methods are 19% and 10%, respectively. The risk treatment plant failure was found to be within the low to medium range. For risk assessment, multiple components were found to influence the failure of treatment plants.  Our evalutation showed that the following items were ranked as highest to lowest to influence the treatment plant failure: inappropriate tank design, power equipment failure, failure of transmission line, and inadequate repair and maintenance of the pumps.


Main Subjects

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