10 research outputs found
Assessment of the Potential Flood Hazard of the Larbaâ Wadi, Rural Center of Sebt Boukellal, Taza, Morocco
No full textFlood risk management often requires the use of geomorphological features to identify flood zones, and the use of hydraulic models to predict inundation dynamics and related impacts on the surrounding area. In this study, we used a hydraulic river simulation model to identify potential flood-prone zones on a small scale. It concentrated on a 2.5-kilometer section of the Larbaâ Wadi, which crosses the rural center of Sebt Boukellal. For estimating the peak discharge that occurs in the return periods of 10, 20, 50, and 100 years of the drainage area, we used the Rational method. Standard tables to estimate Manning’s coefficient and direct field measurements to feed the model. Model simulation has shown stability of the steady state, which witnesses the accuracy of the estimated and measured characteristics of the river system. During the calibration phase, we compared the model outputs to the observed floods and made adjustments to align the simulation with the field observations. Indeed, the 50-year flood remarkably matched the extent of the flood that occurred on September 27, 2000. The obtained results have shown that even for a 10year return period, the overflow affects properties within the floodplain. The 100-year flood exceeded the river’s capacity, causing water to spill onto the rural center’s streets and cultivated fields. The water level reached an elevation of 552.14 meters at Sebt Boukellal’s marketplace. These results were consistent with recent floods and confirm previous observations, indicating that the model precisely predicted the river’s behavior. The findings have shown that floods spanned large regions and suggested urgent intervention to protect lives and properties
Prioritising the sub-watersheds of the Oued El Abid basin upstream of Oum Er-Rbia using Fuzzy Analytic Hierarchy Process (FAHP) and geographic information systems (GIS)
No full textStudying watersheds is essential for understanding their morphological and hydrological dynamics, especially those located in mountainous areas with significant elevations and steep slopes, such as the Oued El Abid, one of the secondary watersheds in the Upstream Oum Er-Rbia basin. The study area includes 45 sub-watersheds. The aim of this study is to identify their priorities based on processing their morphometric characteristics using Geographic Information Systems (GIS) and the Fuzzy Analytic Hierarchy Process (FAHP). To prioritise the sub-watersheds, 18 morphometric indicators were analysed, including cadastral, geometric, and linear indicators. The (FAHP) approach enabled us to categorise these sub-watersheds according to their need for intervention. The study results revealed that 6 sub-watersheds were of high priority, 9 were of medium priority, 11 were of medium priority, and 19 sub-watersheds were of weak or very weak priority. These results confirm the benefits of using Geographic Information Systems and the Fuzzy Analytic Hierarchy Process to determine their priorities for implementing interventions, in order to protect them from risks and enhance their sustainability
Assessing Climatic Variability in Data scare regions of Morocco: Drought Periods and Exceptional Precipitation Events
No full textThe southern Mediterranean region is characterized by significant climatic variability, which profoundly affects precipitation patterns, a critical water resource. To explore this variability, we conducted a comprehensive statistical analysis of the upper Larbaâ basin, situated at the edge of the Eastern Rif Mountains. This area has been experiencing atypical weather events, including sudden flooding and extended drought periods. Our research involved a thorough analysis of monthly and annual precipitation data spanning 65 years, from 1958 to 2023. The homogeneity test revealed a disturbance in the time series from the late 1970s to the early 1980s across all monitored rainfall stations. Utilizing the Moving Average and Inverse Distance Weighting (IDW) model, we identified variations in rainfall amounts, demonstrating a notable trend from the southwest to the northeast of the basin. Furthermore, correlation analysis between precipitation levels and the North Atlantic Oscillation (NAO) index showed an inverse relationship, particularly evident in the northwestern section of the watershed. The EM index indicated a drought duration ranging from 33 to 36 years within the observed time frame, with one-third of the sampling classified as normal drought and two instances categorized as severe events according to the Standardized Precipitation Index (SPI). Our findings suggest that the Pearson type III distribution is the most appropriate for estimating the return periods of extreme precipitation in Taza, whereas the Gumbel distribution is better suited for Sebt Boukellal. We record precipitation levels of 45 mm in Taza and 54 mm in Sebt Boukellal for a return period of 5 years and rise to 88 mm in Taza and 95 mm in Sebt Boukellal for a return period of 100 years
Assessing Climatic Variability in Data Scare Region of Morocco (UpperLarbaâ Basin): Drought Periods and Exceptional Precipitation Events from 1958 to 2023
No full textThe southern Mediterranean region is characterized by significant climatic variability, which profoundly affects precipitation patterns, a critical water resource. This region has been experiencing atypical weather events, including extreme precipitation and extended drought periods. The aim of this study is to investigate the climatic variability over data-scarce regions. To attend to this objective, we conducted a comprehensive statistical analysis within the upperLarbaâ basin, as a case study, situated at the edge of the Eastern Rif Mountains. Our research involved a thorough analysis of daily, monthly, and annual precipitation data spanning 65 years, from 1958 to 2023. The homogeneity test revealed a disturbance in the time series from the late 1970s to the early 1980s across all six rainfall stations used. Utilizing the Moving Average and Inverse Distance Weighting (IDW) model, we identified variations in rainfall amounts, demonstrating a notable trend from the southwest to the northeast of the basin. Furthermore, correlation analysis between precipitation levels and the North Atlantic Oscillation (NAO) index showed an inverse relationship, particularly evident in the northwestern section of the watershed. The Evapotranspiration Moisture Index (EMI) showed that drought lasted between 33 and 36 years, with one-third of the samples considered normal drought and two cases labeled as severe based on the Standardized Precipitation Index (SPI). Our findings suggest that the Pearson type III distribution is the most appropriate for estimating the return periods of extreme precipitation in Taza, whereas the Gumbel distribution is better suited for Sebt Bouklal. We recorded precipitation levels of 45 mm in Taza and 54 mm in Sebt Bouklal for a 5-year return period. For a 100-year return period, the figures increased to 88 mm in Taza and 95 mm in Sebt Bouklal
Assessing Climatic Variability in Data scare regions of Morocco: Drought Periods and Exceptional Precipitation Events
No full textThe southern Mediterranean region is characterized by significant climatic variability, which profoundly affects precipitation patterns, a critical water resource. To explore this variability, we conducted a comprehensive statistical analysis of the upper Larbaâ basin, situated at the edge of the Eastern Rif Mountains. This area has been experiencing atypical weather events, including sudden flooding and extended drought periods. Our research involved a thorough analysis of monthly and annual precipitation data spanning 65 years, from 1958 to 2023. The homogeneity test revealed a disturbance in the time series from the late 1970s to the early 1980s across all monitored rainfall stations. Utilizing the Moving Average and Inverse Distance Weighting (IDW) model, we identified variations in rainfall amounts, demonstrating a notable trend from the southwest to the northeast of the basin. Furthermore, correlation analysis between precipitation levels and the North Atlantic Oscillation (NAO) index showed an inverse relationship, particularly evident in the northwestern section of the watershed. The EM index indicated a drought duration ranging from 33 to 36 years within the observed time frame, with one-third of the sampling classified as normal drought and two instances categorized as severe events according to the Standardized Precipitation Index (SPI). Our findings suggest that the Pearson type III distribution is the most appropriate for estimating the return periods of extreme precipitation in Taza, whereas the Gumbel distribution is better suited for Sebt Boukellal. We record precipitation levels of 45 mm in Taza and 54 mm in Sebt Boukellal for a return period of 5 years and rise to 88 mm in Taza and 95 mm in Sebt Boukellal for a return period of 100 years
The climatic evolution of the Inaouen River Basin in Morocco: Rainfall variability and its connection to the North Atlantic Oscillation
No full textThe Inaouene basin is considered among the basins most subject to rainfall variability, marked by sometimes exceptional dry periods (as low as 252.2 mm) and rainy periods (up to 1129 mm), as recorded at the Taza station, due to the variability of atmospheric factors that control atmospheric circulation, in particular the North Atlantic Oscillation.This study therefore aims to know the impact of this oscillation on the variability of rainfall by calculating the standardized precipitation index and the correlation coefficient. The study revealed that the dominance of the positive phase of the North Atlantic Oscillation since the end of the seventies had a major role in the absence of moist air masses towards Morocco, which caused the stability of climatic conditions of drought in the study area, with the presence of some extreme rainfall events, in which the evidence of the North Atlantic Oscillation is weak
Compounding Morphometric Parameters for watersheds Prioritization in Data-Poor Regions: Case Study of a Semi-Arid Area, Northern Morocco
No full textThis study investigates the vulnerability of the Ouerrha watershed in northern Morocco using the compound parameter method. The watershed was segmented into 40 distinct sub-watersheds, labeled SW 1 to SW 40. Geographic Information Systems (GIS) and Remote Sensing technologies were used to generate foundational data and support a thorough analysis. A variety of mathematical equations were applied to compute the parameters of the watershed. Key morphometric parameters, including relief, linearity, and shape, were integrated to assess the characteristics of the sub-watersheds. The findings reveal that SW8, SW9, SW14, and SW16 are classified as high-priority areas for immediate intervention due to their significant vulnerability to erosion and degradation. Moderate priority is assigned to sub-watersheds 4SW, 5SW, 13SW, 15SW, 17SW, 32SW, 34SW, 36SW, and 38SW. The remaining sub-watersheds (SW1, SW3, 7SW, SW18, 24SW, SW26, 27SW, 28SW, 31SW, SW37, and SW40) are categorized as low and very low priority, indicating a greater degree of stability and resilience against environmental stress, with reduced risks from runoff or erosion. This study illustrates the importance of numerical methods in identifying natural challenges and enhancing the accuracy of sub-watershed prioritization for effective management strategies
Investigation of the hydrochemical quality of surface waters of the Oued Inaouen watershed near the Driss 1er dam (Morocco) using multiv
No full textThis study, conducted from 2021 to 2023, aimed to determine the physico-chemical quality of the surface waters of the Oued Inaouen watershed near the Idriss 1st dam, and to identify existing pollutants and their origins. The research included spatio-temporal monitoring of 26 surface water stations.
Results showed a spatio-temporal differentiation influenced by natural and human factors. The right bank exhibited significant mineralization, while the left bank had soft water due to Middle Atlas liasic limestones and dolomites. Multivariate statistical methods and diagrams (Piper, Schoeller, and Wilcox) were used for hydrochemical classifications and water quality assessment.
Over time, surface waters became increasingly enriched with BOD5, COD, NO3-, and NO2-, particularly downstream where more discharges occur. Pollution is linked to untreated household and industrial waste (notably Olive Mill Waste) and agricultural runoff from fertilizers, with greater enrichment during summer and autumn due to low upstream flows
Investigation of the hydrochemical quality of surface waters of the Oued Inaouen watershed near the Driss 1er dam (Morocco) using multivariate statistical methods and diagram analysis
No full textThis study, conducted from 2021 to 2023, aimed to determine the physico-chemical quality of the surface waters of the Oued Inaouen watershed near the Idriss 1st dam, and to identify existing pollutants and their origins. The research included spatio-temporal monitoring of 26 surface water stations.
Results showed a spatio-temporal differentiation influenced by natural and human factors. The right bank exhibited significant mineralization, while the left bank had soft water due to Middle Atlas liasic limestones and dolomites. Multivariate statistical methods and diagrams (Piper, Schoeller, and Wilcox) were used for hydrochemical classifications and water quality assessment.
Over time, surface waters became increasingly enriched with BOD5, COD, NO3-, and NO2-, particularly downstream where more discharges occur. Pollution is linked to untreated household and industrial waste (notably Olive Mill Waste) and agricultural runoff from fertilizers, with greater enrichment during summer and autumn due to low upstream flows
Assessment of the hygienic quality of well and spring water: A case study of the Oued Leben watershed (Central Prerif, Morocco)
No full textThis study aimed to determine the physical, chemical, and bacteriological quality of groundwater in the Oued Leben basin and to identify the pollutants present and their origins. The research included a spatial study of 37 groundwater stations over a period of nine months (September 2024 to June 2025). The results showed spatial differentiation influenced by natural and human factors. The groundwater analyzed shows a deterioration in its physical-chemical and bacteriological quality, expressed by a high load of pathogenic bacteria and high salinity downstream of the Oued Leben, reaching 8.60 g/L in P1 and P10. This leads to a considerable deterioration in groundwater quality, calculated at approximately 86.5% of points with poor to very poor quality, thus rendering it unfit for human consumption. This deterioration depends mainly on various natural and anthropogenic factors
