The looming threat posed by climate change-fueled droughts has triggered a slew of projects concerned with the reuse of treated wastewater for agricultural purposes. Across the globe, there is also a growing interest in the direct consumption of treated wastewater. Whilst the requisite technology is well established and safety can be guaranteed, the instigators of these projects still anticipate consumer resistance. However, there are currently few studies that provide insight into the public acceptance of treated wastewater. Moreover, the results of these studies are often inconsistent or inconclusive, particularly in regard to the relationship between the acceptance of wastewater reuse and environmental concern. Using representative survey data gathered from 300 respondents living in Flanders, Belgium, we show that water conservation behaviour and a sense of environmental group-efficacy positively affect public acceptance. Our study also demonstrates that feelings of disgust and fear of contamination are key drivers of consumer resistance to wastewater reuse and potentially override environmental concern. In the discussion, we propose an alternative approach to better understand consumer's environmental attitudes and their resistance to the use of treated wastewater. In the conclusion, we briefly highlight the relevance of our findings for public communication and policy.