Public risk perceptions of advanced water purification in an arid urban region of the U.S. southwest: A mixed methods...

As water utilities implement potable reuse technology, there is a need to understand how to increase public acceptance and trust in public water supplies. The study objective was to use surveys and interviews in a large metropolitan area in Arizona to characterize tap water and advanced purified water acceptability, and factors contributing to (un)acceptability. Participants were recruited through a water utility email listserv for participation in an online REDCap survey and/or 1-hr Zoom interview. Surveys and interviews inquired about perceptions of tap water safety, familiarity with water reuse terms, acceptability of direct potable reuse (called "advanced water purification" in our study for consistency with state messaging), and rationales related to acceptance. Four hundred seventy-nine individuals participated in the survey, and twenty-two individuals participated in the interviews, with roughly comparable demographics for our city of interest but with slightly higher levels of household income and education. Only 36 % of survey respondents use their tap water for drinking water supplies, but (42 %) would be open to drinking advanced purified water. Semi-structured interviews were conducted in 2024 on risk-based thinking to evaluate how advanced purified water may compare to current drinking water safety and analyzed with inductive thematic analysis. Survey and interview participants wanted more reassurances (e.g., third party testing and opportunities for hands-on testing). Water utilities should prioritize transparent communication strategies, including sharing detailed third-party testing data and direct community engagement initiatives, to enhance public acceptance. Utilities can build trust through clear comparisons between advanced purified water and current tap water quality.