After the floods of recent years, the summer flood of 2021 has once again shown that, on the one hand, the vast majority of dams in the affected areas in Germany have fulfilled their tasks and made a contribution to flood protection even under this extreme impact. On the other hand, the example of one dam made it clear that there are (residual) risks that can bring a dam structure to the brink of failure, especially in the case of effects beyond the design assumptions. In this case, an embankment dam was massively damaged by overflow on the downstream side. Against this background, this paper explores the question of which technical input can be given when drawing up emergency plans and how the legal and technical requirements are to be met. At the end of the considerations, in addition to other possible measures, there is the realization that (special) hazard maps for a hypothetical flood propagation in the downstream reach are necessary in order to adequately protect people and, if necessary, property assets.