Long-term research has identified significant water contamination and associated poor health outcomes in the indigenous community of Alpuyeca, located in south-central Mexico. We set out to develop a popular education initiative in this community to improve water, sanitation and hygiene (WaSH) knowledge and practices. In order to avoid recreating hierarchical power dynamics in this vulnerable community, a participatory action research (PAR) design was used, wherein the community took leadership and facilitation roles in each stage of the research process. In qualitative interviews and design sessions, community members identified unsatisfied WaSH needs in households and community institutions and articulated a clear worldview of the spiritual role of water, which guided the development of a series of popular education-based workshops and discussions. The popular education initiative process was documented with a mixed methods framework, using before-and-after surveys, semi-structured interviews and participatory observation. Increases in knowledge and practices related to water purification, water consumption and hand hygiene were noted in the community. The community identified locally installed and managed ecotechnologies as a key opportunity for sustainable development, community participation and the adoption of water and sanitation systems, compatible with public imaginaries of the role of water.