In the second half of the 20th century, due to the increased need for electricity a large number of hydropower facilities has been built. When constructing such facilities, it is necessary to carry out an assessment of the environmental impact of the facility. In order to provide the safety of the population around the infrastructure, a safety plan for the emergency solutions has to be prepared. The basis of such a plan is the hydraulic calculation of the possible dam break of the structures, also presented in our master thesis. The first part of the thesis presents dams and potential causes that could cause a collapse. The following is a review of theoretical background of hydraulics and the legislation governing the field of dams in Slovenia. Theory is then followed by analysis of the Melje dam, which is a part of Zlatoličje hydroelectric power plant. Afterwards, we have performed a hydraulic calculation of a possible dam failure. As a part of the calculation, we have presented the complete system of the hydroelectric power plant, the data of the hydraulic model and all assumptions needed to build the model. Since the Melje dam has already been analysed and the dam break flood wave was already calculated as a part of the 1977 Porušitev Dravskih stopenj project, we have based our model on the assumptions used in aforementioned project. Due to the fact that water spills over flood plains at high flow rates, we have created a two-dimensional model and compared obtained results with a one-dimensional model at high water flow. The results indicate that the worst case scenario would be dam-break of pillars between gates at initial flow of Qmax = 4650 m3/s. Under more reasonable assumptions, none of the dam-breaks would seriously endanger the populated areas on the section between the Melje dam and the Markovci dam.