To explore social determinants of drinking water beliefs and practices among the Tz'utujil Maya of Santiago Atitlán, Guatemala, through analysis of demographics, socioeconomic status, memory of historical events, sensory experience, and water attitudes. Parallel mixed (qualitative and quantitative) methods, including participant observation, in-depth interviews based on a purposive sample, and 201 semi-structured interviews based on a regional quota sample, were used to collect data from March 2007 to August 2008. Data analysis included the use of grounded theory methodology and Pearson's chi-square test for independence. Qualitative results based on grounded theory highlighted how memory of the Guatemalan Civil War and Hurricane Stan, attitudes about Lake Atitlán water, and the taste and smell of chlorine influenced Tz'utujil Maya drinking water beliefs. Quantitative survey results revealed that differences in ethnicity, literacy, years of schooling, distrust of the water supply during the Civil War and Hurricane Stan, and current beliefs about Lake Atitlán and tap water quality were associated with significantly different water self-treatment practices. In accordance with social determinants of health paradigms, demographic, socioeconomic, social, cultural, political, and historical factors continue to be significant determinants of water-related health. Public health water interventions must address inequalities related to these underlying factors in order to achieve maximum effectiveness.