In this project we examine the geographical availability of water resources for persons experiencing homelessness in Phoenix, Arizona, U.S.A. Persons experiencing homelessness spend a significant portion of their time outdoors and as such have a higher risk of dehydration, heat-related illness, and heat stress. Our data was collected using archival data, participant- observation, focal follows with water distributors that serve homeless populations, phone and internet surveys with social service providers, and expert interviews with 14 local service providers. We analyzed this data using methods for thematic coding and geospatial analysis. We find that the sources of water and geographic availability vary across the economic sectors of the population and that they become more unconventional and more difficult to access with further isolation. We conclude that many persons who are experience homelessness have inconsistent and unreliable access to water for hydrating, maintaining hygiene, cooking and cleaning for reasons that are largely due to geographic inaccessibility.