The paper focuses on one of the most productive wheat-growing regions in the entire Roman Empire, the Arsinoite nome (modern Fayum) in Egypt. Towards the end of the third century CE, multiple formerly thriving farming villages at the edges of the district went into decline and were eventually abandoned. This paper presents a new perspective on causes of this abandonment by synthesizing existing research. The papyri as well as the archaeological record imply that irrigation problems arising simultaneously from the third century CE lay at the heart of the problem and led to the progressive desertification of formerly agricultural land. The surviving documentation allows us to trace what increasing water stress meant on the ground for the local population and what adaption strategies they undertook to deal with the degradation and desertification of their farmlands. While socio-economic factors certainly played a role in the decline of these settlements, a change in environmental conditions should be considered as well. In fact, natural proxies record a general shift in East African Monsoon patterns at the source areas of the Nile and consecutively lower Nile flood levels from the beginning of the third century on.