“…For instance, when it comes to transboundary groundwater resources, there is no formal agreement on the groundwater aquifer between Botswana, Namibia, and South Africa, but technical cooperation, promoted also by the UN through UNESCO, is very active and promising [37]. Similarly, the Guarani Aquifer System (GAS), a groundwater basin shared between Argentina, Brazil, Paraguay, and Uruguay, shows that even before the ratification of the GAS agreement, bilateral cooperation at the local level was successfully happening, for instance, in the case of the municipalities of Concordia (Argentina) and Salto (Uruguay) [38]. Regardless of the GAS preratification of the agreement, Botswana, Namibia, and South Africa would have all scored zero according to the SDG 6.5.2 Indicator.…”