Industrial accidents triggered by floods are among the most frequent NaTech accidents – industrial accidents triggered by natural event. Aside from the impact of floodwater on the operation of electrical equipment, the hydrostatic and dynamic forces of flood can cause structural damages to chemical/process facilities. Structural damages can be in form of displacement, floating, overturning, and shell buckling of vessels. Besides, the displacement of process vessels can lead to the damage of pipelines connected to them. Water dispersion and reaction of released chemicals are the main causes of severe consequences in terms of environmental damages (e.g., soil contaminent, widelife damage, etc.) and water resource pollutions (leakage of toxic substances to groudwater/surface waters). The ignition of flammable/explosive chemical substances (e.g., hydrocarbons) floating on the floodwater can be another potential source of hazard. In PEC flood risk assessment, the impact of floods on the integrity of chemical/process vessels (structural damage) will be investigated, with a particular emphasis on vessels containing large inventories of hazardous substances, such as storage tanks.