This article presents new approaches to water diplomacy connected with the United Nations 2030 Agenda. The research question is what is the role and significance of water diplomacy for Sustainable Development Goals (SDGs) and global security architecture? The paper is based on the theory of interdependence. To illustrate this concept, the author used several case studies to identify the international security role of water diplomacy in the context of SDGs. The case studies point to the greater likelihood that wars in the twenty-first century will be due to freshwater disputes; water diplomacy should be a crucial instrument for the SDGs implementation. Water diplomacy has the potential to become an effective platform for international cooperation in the face of many current and future global water challenges. Water diplomacy combines preventive and reactive measures, as well as the mediation and implementation of solutions. It is crucial for regional and world security. The results of this paper show future research directions on water diplomacy.