Increasingly frequent disturbances such as droughts, earthquakes and terrorist attacks have severely affected the interdependent infrastructure of industrial parks. It is necessary to explore the relationship between the interdependence degree and stability of the infrastructure and ensure that the infrastructure systems can withstand the impact of emergencies from natural disasters, industrial accidents, or malicious attacks. The water system of an industrial park is investigated in this work, which proposes a method combining Process Integration with the inoperability input-output model (IIM) for risk analysis. First, Process Integration is used to generate optimal water network alternatives under different optimisation conditions. The IIM was next established to investigate the inoperability, elasticity, and flexibility of each alternative after a disturbance occurs. Finally, practical risk mitigation measures are discussed based on the analysis. Results showed that when PI is used to help the park save water, it also leads to the high interdependency, which makes the park difficult to withstand the shock of external disturbances and causes cascading damage.