Community Resilience and Consequence Management of Pollution Intrusion Into Water Distribution Network: A Case Study

Abstract

Contamination intrusion into the municipal water distribution network (WDN) without appropriate action may lead to disaster. This study examined community resilience (CR) and its effects on optimal consequence management (CM) plans. CR was measured by five dimensions: governance, preparedness, social learning, social trust, and collective efficacy. The above dimensions were measured by conducting a structured questionnaire survey, and CR was then defined using structural equation modeling. Furthermore, water usage changes of consumers in response to contamination intrusion were investigated through questionnaires. NSGA-II algorithm was used for CM optimization with the objectives of minimum contaminated water ingestion and operational interventions, and the results were presented in three scenarios. The proposed method was evaluated in a WDN in the southeastern part of Tehran. The CR was quantified as 2.58 out of 5 using a one-sample t-test which shows that the studied community is not resilient. Without considering the demand changes during WDN contamination, the maximum total ingested polluted water is 184 Kg. Considering demand reduction (scenario 2), it diminishes to 154 Kg. As CR was identified as one of the significant factors for water demand variations via linear regression analysis, by empowering CR by one point (scenario 3), contaminated water ingestion decreases to 151 Kg. The immense difference between the base scenario and the two others (16% and 18% reduction in total ingestion) indicates that it is vital to consider people’s reactions in CM plans and enhance CR to preserve public health.