This paper presents a phenomenon that has received limited attention so far, namely the curtailment of the armament produced by Switzerland in the prospect of WWII. Notwithstanding its neutrality principle, Switzerland has been compelled to arm itself to face the Axis' ambitions. Due to its non-involvement, Switzerland was left with significant stockpiles of armament once peace was restored. Numerous governments worldwide also had to deal with this issue. In order to rapidly get rid of stockpiles of conventional and chemical munitions and to avoid security concerns, diverse kinds of waste management approaches have been used. The objective of this paper is threefold: - First, it aims to characterize the Swiss policy of ammunition repository following WWII, particularly because their land disposal was a great threat to human security. This paper underlines the uniqueness of the Swiss' position compared to other countries that have been at war and that also have discarded ammunitions into maritime areas and/or freshwaters. - Second, it intends to describe this case of waste management and its impacts on lake environments through the legislative development of water protection. In relation with the emergence of the Swiss environmental consciousness, this study highlights the existing relationships between munitions dumping and water protection. - Third, it aims to characterize the two distinct situations about the dumping of munitions and their legacy in Switzerland: the first concerns public actors, like Federal factories, while the second involves private actors and factories. Such historical study is based on semi-structured interviews, analysis of both scientific and historical reports, and archival research methods (e.g. newspapers and federal and cantonal administrations). To conclude, this study intends to raise awareness about the unique political, geographical, environmental, and historical situation of Switzerland on the genuine ecological time bombs that are sleeping at the bottom of Swiss lakes.