Dams provide many benefits for our society such as the supply of drinking and irrigation water, the generation of electric power and flood protection. However, when a dam fails, large quantities of water are suddenly released, creating major flood waves capable of causing damages to downstream areas. Therefore, every dam requires an Emergency Action Plan (EAP) guideline for disaster preparedness. In EAP guidelines, there is emergency management including how to communicate people do the right thing during and after a disaster to have the best chance of survival with as little loss as possible. Effective communication is essential during each phase of emergency management. In the mitigation and preparedness phases, communication helps to exchange and confirm information and efforts to be prepared by appropriate stakeholders and organizations before an event. This paper will describe effective communication using visual communication media concept in leaflet and video to minimize the risk of loss of life and property downstream. Based on the dam failure modeling, the people can know detailed information about the risk area, the property and evacuation procedure to minimize flood hazard.