Risk Analysis of Wastewater Reuse in Agriculture Using Baysian Network

The advantages of treated wastewater such as decrease of water resource limitation and environmental pollution reduction caused to be considered as a valuable source in irrigation. However, the probable pollutants in the treated wastewater cause some restriction on its reuse. Risk assessment is an important tools in understanding the potential risks of a project and its potential consequences. In this study, the risk assessment of wastewater reuse is done using the technique of Bayesian networks. In this method, a network of cause and effect is created and two indexes of hazards and impacts are defined. Hazards are due to treated wastewater pollutants and impacts referred to the effects of hazards on human and plant as the main receptors in this analysis. The present survey is applied for the risk analysis of wastewater reuse of Alborz industrial park treatment plant located in suburb of Ghazvin city for irrigation of adjacent farmland. Results showed a 46% risk for human and 38% for the plant which the cadmium, detergent and nitrate have the highest share in the total assessed risk. Mitigations measures for risk reduction includes construction of pretreatment, precise supervision and improve the operation and continuous monitoring.