As climate variability and uncertainty are increased, reservoir(dam) collapse occurs every each year, and social and economic losses due to the collapse of reservoirs affect the convenience and national security of the people. In particular, there are a lot of concern about human lives and property damage in small and medium-sized reservoirs of local governments which are lack of flood control capabilities and lack of professional manpower for the management. In this study, 94 cases of reservoir collapse data caused by localized heavy rain, were constructed. And 12 categories based on specific and geometrical characteristics were classified into four categories, for 11,395 small and medium-sized reservoirs under 300,000 tons completed by 1970. The 1,014 reservoirs in 109 municipalities derived into the collapse characteristic category. Finally, the 964 reservoirs were derived, through relationship analysis between emergency discharge technology and specific information of reservoir. Although this study results are able to used as basic information on the disaster management operation system of local governments by deriving risky reservoirs from this data analysis and classification system.