Enhancing water management and governance Despite the relatively large amount of attention that infrastructure receives in adaptation measures, in many cases, the key is not in the robustness or flexibility of the infrastructures but rather, it is found in safeguarding the availability of resources and the sustainability of the ecosystems. As an example, two serious threats to the human rights to safe drinking water and sanitation are the overexploitation of aquifers and the prioritization of over-allocation of water rights over the sustainable availability of flows in ecosystems. Both of these problems have been created by unsustainable management approaches and will undoubtedly be exacerbated by climate change. It is important that adaptation measures take into account current and future water demand in each basin and even between countries, where transboundary basins or aquifers are involved, to ensure that activities are viable and do not undermine the provision of water for drinking, hygiene, and sanitation, especially for vulnerable populations. Moreover, sustainable adaptation strategies in the field of water management should include: Basing water planning and management on both existing surface and underground water resources, and the expected availability of water under plausible scenarios of climate change. It is essential to contemplate a diversification of surface and underground water sources, as well as a prioritization of safe drinking water; Promoting water tariff systems that guarantee access to safe drinking water and sanitation services for everyone, including those who are not capable to pay, with rates that encourage efficient use and minimize the water footprint on ecosystems - for example, systems with increasing rates for consumption blocks; and Balancing the use and allocation of surface water and groundwater according to the level of rainfall. During periods of high precipitation, the use of surface water should be favoured, and infiltration to aquifers should be encouraged to maintain or restore the level of groundwater reserves while preserving their quality. Thus, during periods of drought, the use of groundwater may be intensified, ensuring in any case an order of priority in the different uses, so that in no case is there a risk to the fulfilment of the human rights to drinking water and sanitation. It is and will be essential to avoid overpumping and to prevent their pollution, especially by protecting their recharge areas. Building resilience of people in vulnerable situations Most people without access to safe drinking water are not living in waterless (arid) environments. Rather, they are people living in poverty who lack access to drinking water for their basic needs while the available drinking water is served to those who can afford it or they are people living next to polluted rivers, lakes or aquifers, which are their source of drinking water. The fundamental key to reducing the risks and impact of climate change on drinking water lies in recovering the good functioning of aquatic ecosystems and addressing the socio-economic inequalities that exacerbate risks for groups in situations of vulnerability. 4