As global water scarcity intensifies, potable water reuse, the process of treating wastewater to a quality suitable for drinking water, offers a path toward sustainable water management. However, despite its growing technical viability, wide-spread adoption has been hampered by public opposition, often reductively dis-missed as lacking ‘social acceptance’. Potable water reuse blurs the long-established societal and infrastructural separation between wastewater and drinking water, leading to concerns about safety, system reliability, trust in authorities, and disgust (the ‘yuck factor’). This dissertation argues that although addressing social acceptance is critical, current approaches remain largely insufficient and overlook vital social and ethical concerns. For instance, the dominant paradigm of spreading information to combat a lack of knowledge must give way to approaches that better address all relevant public concerns. Moreover, by shifting the lens to incorporate ethical acceptability, this work uncovers critical but neglected issues, including the potential marginalisation of nonvocal publics, the risk that potable water reuse entrenches technological lock-in through unsustainable infrastructure, and unresolved challenges in managing concentrated waste streams. Ultimately, this work highlights that social acceptance and ethical acceptability must be treated in tandem to ensure the desirable and responsible development of a technological system – a strategy for which this dissertation lays the groundwork.

As global water scarcity worsens, potable water reuse is increasingly considered a vital solution for augmenting water supplies. However, public acceptance remains a significant barrier, presumably because of a misalignment between the public values reflected by these systems and those that are held by the communities that these systems intend to serve. This study explores this potential misalignment by systematically identifying and analysing the most prevalent values inscribed in academic research on potable water reuse. We employ a mixed-methods approach, combining probabilistic topic modelling with thematic analysis of 2940 academic publications to identify and conceptualise latent values discussed in the literature. Our findings suggest that the values ‘reliability’, ‘sustainability’, ‘health’, and ‘safety’ are most prevalent but that their conceptualisation remains largely ambivalent. For example, sustainability exhibits an ambivalent relationship with safety, sometimes conflicting and sometimes supporting, depending on the research perspective. Crucially, this research demonstrates a predominantly technocentric understanding of these values. While this technical focus is undeniably important, it also risks overlooking broader societal concerns and other value interpretations. This research highlights the need for a more value-sensitive approach to ensure a more responsible potable water reuse, incorporating a wider range of public values to promote the system’s social and ethical desirability.

Introducing emerging technologies is often seen as successful when social acceptance has been achieved. In the case of ‘wicked’ problems, social acceptance might be an insufficient quality criterion for the desirability of technological developments, because the focus on social acceptance can risk overlooking crucial ethical considerations. As such, this paper addresses the research question of whether technology governance frameworks can go beyond mere social acceptance issues and incorporate ethical considerations. By exploring three projects in which potable water reuse has been introduced, we have identified the limitations of common governance approaches to enhance social acceptance, including common participation and ‘Opening Up’ participation strategies. Our explorative study indicates that even an ideal participation strategy is insufficient to ensure ethical acceptability due to the lack of critical reflection on the problem this technology development is solving. If a given problem is too narrowly defined to artificially favor one solution over another, the exploration of alternative solutions will be hindered, potentially reinforcing unsustainable practices. To extend on existing approaches to participation, we propose a socio-ethical assessment framework that integrates social acceptance measures with ethical acceptability considerations to address these shortcomings. This framework emphasizes the importance of ethical participation, including the representation of marginalized voices, future generations, and non-human entities. It also urges to critically examine the framing of the problem itself, acknowledging the wicked nature of issues like water scarcity. By doing so, technology governance can become more responsible by aligning societal and ethical considerations.

With the increasing reliance on technological advancements, it becomes imperative to critically examine and evaluate their implications on society and the environment. The concepts of acceptance and acceptability have gained prominence among researchers shaping technology implementation strategies. However, the lack of precise definitions for these concepts leads to diverse interpretations, compromising their usefulness in technology development and impeding further progress in research endeavours. This paper illustrates how these important concepts have been used in the energy technology discourse and develops a schematic overview highlighting the varied overarching interpretations of these concepts: the funnel of acceptance and acceptability. It underscores how different research levels – institutional, societal, and individual – affect the relevant understanding of these concepts. The funnel metaphor emphasises the interconnectedness of these interpretations and underlines the importance of addressing all research levels to ensure technology implementation processes advance in a desirable and responsible manner.