Climate change will heavily impact on water and aggravate existing inequalities. These inequalities result importantly, but not exclusively, from actual physical shortages of water. Quite often, they are also the result of social conditions. The UN Sustainable Development Goals (SDGs) repeatedly address the issue of water (such as SDG 2, 6 or 14). This paper deals with normative standards for a fair distribution of water. By going so, it is critical and constructive contribution to the debate about water invigorated by the SDGs. It aims to identify potential injustices (critical) and argues for more just solutions in the face of changing environmental conditions (constructive). The paper starts by outlining that the aim of sustainable development is about safeguarding the right to live in dignity for all present and future generations. Moreover, it obligates that the natural and social preconditions for such a life are to be protected and supported. Yet, the difficulty in protecting a life of dignity lies in defining it by way of universalistic ethical principles without ignoring the diversity of particular ways of living it. This is why this paper, secondly, draws on the deontological approach by the social ethicist Alan Gewirth in order to determine what people need to live a life of dignity. Moreover, the paper applies these insights to water and water governance. Finally, it will briefly discuss implications for a fair distribution of water after the adoption of the SDGs and Paris.