BackgroundMemory is a collective ownership based on facts and past events. Aristotle and Agostinho were the first philosophers to investigate it, including the dimensions of time and memory inhabited by man. Northeastern Brazil has a rich cultural history linked to water scarcity in the region, one of the main limiting factors to the development of rural populations. Among alternative sources, temporary ecosystems known as rock pools have been used as rainwater storage in arid and semiarid regions around the world. Considering the hypothesis that the arrival of perennial water sources can impact memory transmission between generations, this study aimed to analyze the popular knowledge about rock pools, a traditional and ancient water source.MethodsInformation about the use and management of rock pools in the Brazilian semiarid region was collected by interviewing residents from a small city near an inselberg. The interviews presented specific questions about the structure, characteristics, traditional knowledge, use and management of rock pools. During sampling, 20 rock pools were visited by two key informants, i.e., those with more experience and knowledge about these ecosystems.ResultsOur results identified that the use and management of rock pools were reduced after the Brazilian government implemented the One Million Cisterns Project. Therefore, despite the historical relevance of these water bodies, their uses were forgotten by most of the inhabitants and those from neighboring locations, remaining for domestic use.ConclusionsResults about traditional knowledge indicated that the generation interviewed still remembers such method. However, with the presence of cisterns, the transmission of traditional knowledge about rock pools has decreased between the families and generations, presenting a serious social risk for a region characterized by extreme and prolonged droughts.