Immediately after World War II, many governments around the world needed to get rid as fast as possible of huge stockpiles of conventional and chemical munitions to avoid possible security concerns. Several waste management approaches have been used, including open-pit burning, firing, exploding, dumping and land burial. For a number of reasons, mainly related to cost-efficiency, safety and fastness, the globally most common adopted solution was to dump munitions. A variety of geographic underwater munitions sites have been used, including lakes, ponds, marshes, streams, rivers, estuaries, harbours, canals, seas and oceans. Over time, the emergence of environmental conscience has brought this issue back on the political agenda with a particular attention on environmental risks. This legacy of munitions in varied underwater environments presents risks: exposure and contamination of underwater organisms and ecosystems as well as direct human health impact. With this study, using personal interviews, reports and archival research methods, we intend to raise awareness about the specific political and geographical situation of Switzerland on this subject and to provide an overview of new research results and research gaps about munitions dumped in Lake Geneva. Moreover, our study aspires to highlight the culture of secrecy's capability to interfere with ecological policy, and to become an obstacle to implement proper risk management measures.