An Algorithm for Risk Analysis and Management of Wastewater Treatment Plants

Document Type : Original Article

Authors

1 Professor, School of Civil Engineering, College of Engineering, University of Tehran

2 MSc Graduate, School of Civil Engineering, College of Engineering, University of Tehran

3 MSc Graduate, School of Civil Engineering, College of Engineering, University of Tehran.

4 PhD Graduate, School of Civil Engineering, College of Engineering and Assistant Professor in College of Aburaihan, University of Tehran

Abstract

Wastewater Treatment Plants (WWTPs) are vital infrastructures for ensuring the human and environmental health. Environmental protection, preventing contamination of underground water resources and promoting public health, are the reasons that the WWTPs systems are one of the most important elements in the civilized societies. Failures in WWTPs operation may lead to adverse outcomes such as untreated wastes exclusion from WWTPs containing various chemical and biological pollutants and their entry into the urban environments and agricultural lands. That can lead to serious crises such as outbreaks of contagious diseases in the community. Hence, assessing the potential risks in WWTPs and designing the prevention and mitigation plans are necessary. In this paper, an algorithm has been proposed for risk assessment and management of WWTPs. In the proposed algorithm, the risk of a specific element of a WWTP is calculated by multiplying three parameters comprising probability of failure, intensity of probable damages, and vulnerability of element. The aforementioned parameters is quantified by means of experts and policy-makers’ viewpoints which are elicited from questionnaires. Based on the values of operational risk elements (probability, intensity, and vulnerability), different mitigation or prevention plans could be proposed to reduce risks. The proposed algorithm has been implemented on the Tehran South WWTP as a case study and earthquake risk in "biogas tanks" and the explosion risk in "disinfection units" gained first and second rank in the results, respectively. Result of this study shows that the proposed algorithm can be employed by managers and policy-makers of WWTPs as a robust and practical decision-making tool.

Keywords


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