From field observations in the lower Kert valley and 16 radiocarbon dating measurements, six alluvial units (UF1 to UF6) deposited since about 30,000 years BP have been identified, comprising 18 lithofacies and separated by six incision stages resulting in three alluvial terraces (T1 to T3). While the Late Pleistocene is mainly marked by sedimentary accretion (UF1 forming part of T1), the Holocene is marked by the alternation of major incision (I2, I3 and I4) and accretion (UF2 and UF3) stages, with roughly similar height ranges, between the current river level and polyphased T1 surface. During the Lower and Middle Holocene, this complex morphosedimentary evolution could have been the result of contrasted bioclimatic trends that did not appear during the Late Pleistocene. Human activities modified the earth surface conditions, intermittently during the Middle Holocene, and during the Upper Holocene, inducing new responses from the fluvial geosystem to the environment.

Since the early 1980s, several regions of Morocco have experienced alternating series of wet and dry periods related to climate change, with significant consequences for the country’s economy. This study aims to map flood hazards by using a hydraulic modeling approach, with a specific focus on the Oued (river) Zaouiat Sidi Hamza passing through Zaouiat Sidi Hamza township belonging to the High Ziz watershed (province of Midelt, region of Drâa-Tafilalet, Morocco). Hydraulic modeling and flood simulation were carried out followed by mapping of the flood hazard. The Oued Zaouiat Sidi Hamza River can cause torrential flooding issues, particularly during periods of heavy storms, impacting agricultural land and certain buildings on both river banks. All the cultivated areas developed alongside the river are at risk of flooding. Moreover, undermining and erosion of the river’s banks lead to rising high-water levels and flooding agricultural terraces. The use of geographic information systems and hydraulic modeling tools is essential to gain a deeper understanding of this situation. Also, the mapping of lineaments and fractures in the study area, carried out by satellite image processing, helped to quantify the directional influence of these lineaments on the flow of the hydrographic network, on the orientation of the circulation of surface water, and on the storage of groundwater. According to this study, the most vulnerable areas to flooding and erosion are those that receive the most water in the basin and have steep slopes. Decision-makers can use the results to produce development plans tailored to combat these risks and raise awareness among the population concerned, improving water resource evaluation and forecasting, as well as improving agricultural production.