Application of two-dimensional hydraulic modelling in flood risk mapping. A case of the urban area of Zaio, Morocco

Flood risk mapping is important to prevent damage from flooding in urban areas. In this study, a flood risk map was produced with hydrological and hydraulic data. The methodology implemented in this article was based on both the mathematical calculation of the maximum flow rate and the software Iber 2.4.3 is used as a 2D hydraulic modelling tool verified using field observation data. The flood conditioning factors used in the modelling were precipitation, slope, depth, land use. Other factors, including urban density, socio-economic conditions and the responses of 500 questionnaires distributed to people in the study area, Zaio NORT EAST Morocco, were taken into account to analyze the vulnerability to flooding. A flood risk map was then produced using flood risk and vulnerability maps. The mapping method presented as a precautionary measure against flooding not only alerts the public to flood risk issues and reduces it more effectively in identified vulnerable areas, but also helps the authorities to make decisions about flooding strategies, land use and urban development

Flood Hazard Mapping in Rural Area: Case of Ephemeral Watercourses in SidiBoulenouar Zone

The eastern region of Morocco is characterized by an arid to semi-arid climate. It is often confronted with heavy rainfall episodes that can generate floods that can cause adverse human and property damage. This work studies hydrological risk in the SidiBoulenouar area (Oujda province) to model floods and map risk areas. The method used is to determine the watersheds and their watercourses, then to calculate the flows with the mathematical formulas. Topographic data were extracted from a 12.5-m resolution DEM derived from the ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer). GDEM (Global DEM). The DEM was used to delimit the hydrographic network with ArcMap software. The use of HEC RAS 1D was necessary to delimit the flooding area. The results of the 1D hydraulic modeling of the centennial flood showed that four ephemeral watercourses landlock the rural area of SidiBoulenouar at the time of the floods

Flood risk modeling in the watershed of Charâa stream, Province of Berkane (North-Eastern Morocco)

The knowledge on floods in Morocco is sporadic and scattered between historical writings and natural events following each other in time and space. In this context, the identification of areas likely to be affected by floods is essential for better management of this risk. The present study aims to model the floods at the level of the two sides of the Charâa stream (the side of Berkane and Sidi Slimane Charâ). The methodology followed in this modeling consists of determining the geomorphology of the watershed and studying its hydrology. 2D hydraulic modeling by Iber software makes it possible to follow the Spatio-temporal evolution of the characteristics of a flood. In addition, it allows us to map the hazard. Furthermore, to assess vulnerability to flooding, we referred to land use (physical vulnerability) to study the behavior of runoff water in the face of socioeconomic issues such as buildings, facilities, and the road network. The results showed that: (1) - A predominance of high-intensity flood hazard in the floodplain; (2) - Land with medium and high vulnerability successively constitutes 46.50% and 31.10% of the total studied watershed area

Modeling the risks of marine submersion on the Saidia coastal- Cap de l'Eau (Northeast Morocco)

The coastline is an area of ecological and environmental balance between the continent and the sea. The coastline from Saidia to Cap de l'Eau, located on the Mediterranean coast of Morocco, is the subject of this study. The goal of this work is to produce maps of the risk of marine submersion. The methodology followed consists of entering storm meteorological data and land use data into the Iber 2D software. In addition, we mapped the hazard as well as the vulnerability of this submersion. The results of this 2D modeling of the hazard have shown that the coastline of Saidia - Cap de l'Eau presents a high risk of marine submersion, and this by the water levels rises to more than 4 meters and overflow on a width of more than 20 meters towards the mainland. In addition, the coastal strip constitutes a zone of high vulnerability compared to the continent

Identification of Groundwater Potential Zones (GWPZ) Using Geospatial Techniques and AHP Method: a Case Study of the Boudinar Basin, Rif Belt (Morocco)

The present study aims to delineate the groundwater potential zones (GWPZ) in the Boudinar Basin using geospatial techniques and through an analytical hierarchal process (AHP) method. For multi criteria decision analysis, fifteen thematic layers were integrated into a geographic information system (GIS) environment. In this analysis, each thematic layer is calculated for normalized weights. Furthermore, the consistency index and consistency ratio were calculated to ensure that the result was significant and reliable. The GWPZ map has been categorized into three classes: poor (50.82%), moderate (49.06%), and good (<1.00%). To compare the result, we used four other scenarios of the GWPZ. Two of them are the most similar to our result. Finally, predictive groundwater production and management strategies that ensure long-term sustainability are highly needed