Climate-related events have impacted Puerto Rico unprecedentedly for the past decade. In September 2017, Hurricane Maria impacted the provision of tap drinking water due to power outages. The tap drinking water supply disruptions contributed to water insecurity characterized by the absence of safe, reliable, adequate, and affordable drinking water. Among the most affected in Puerto Rico were the older adult communities, one of the most vulnerable groups. In addition to the disaster-related water insecurity challenges, it has been documented that there is widespread public mistrust of tap drinking water across the island and that people do not consume tap drinking water. Nevertheless, there is limited understanding of why people mistrust tap drinking water. To tackle this gap, this study asks: “Why do older adults mistrust tap drinking water in Puerto Rico five years after Hurricane Maria?” Data collection included household interviews with older adult residents (N = 56) from June 2021 to June 2022 and a community workshop (N = 9) with community representatives in June 2022. Thematic qualitative analysis shows older adults generally mistrust tap drinking water because of its poor quality over the past decade based on the water’s organoleptic qualities (taste, color, and smell). The study outlines a public water crisis where older adults in Puerto Rico have difficulty rebuilding trust in the public water services.