Ethiopia faces a significant challenge in combating soil erosion. This study addresses the concern within Ada’a watershed of the Awash River basin. GIS and the Universal Soil Loss Equation (USLE) Model were used to predict soil loss and the sediment transport index (STI) in the Ada’a watershed of the Awash River basin. RUSLE model required intensive rainfall data registered continuously for 30 min, due to unavailability of this Rainfall data USLE model were preferred. Moreover, USLE model was chosen because of its straightforward methodology and accessibility to data. The study's objectives were to determine the mean annual soil loss rate, STI, and to identify and rank the most important erosion-prone spots for soil conservation planning. Using the interactive Spatial Analyst Tool Map Algebra Raster Calculator in the ArcGIS environment, the mean annual soil loss was estimated based on grid cells by multiplying the corresponding USLE factor values (R, K, LS, C, and P). The STI was also calculated on the Raster Calculator in ArcGIS using flow accumulation and slope gradients. The result shows that R, K, LS, C, and P factor values were estimated in the watershed as 344.9 to 879.65 MJ mm h⁻1 year⁻1, 0.11 to 0.38, 0% to 22.23%, 0 to 1, and 0.55 to 1, respectively. The overall annual soil loss in the watershed ranged from 0 to 457.4 tons ha⁻1 year⁻1. The Sediment Transport Index ranges from 0 to 856.193. The result implies there is increasing rate of soil losses and sediments observed at alarming rate. The highest rate of soil loss was found in the watershed’s lowest parts. Accordingly, sustainable erosion control mechanisms based on topography and land use types are highly recommended, especially in the upper part of the watershed.

Floods are the second most significant hazard in Ethiopia, primarily due to the country’s diverse topography, including highland mountains and lowland plains. The Awash River Basin faces numerous environmental challenges, such as land degradation, topsoil erosion, high population density, water deterioration, wetland destruction, desertification, and salinity issues. Floods exacerbate these challenges, making effective flood hazard mapping vital for land use planning and mitigation strategies. This study aimed to create a GIS-based flood hazard map and estimate annual soil loss using the Universal Soil Loss Equation (USLE) while identifying the primary causes and impacts of flooding and soil erosion in the basin. Key parameters for the flood mapping included elevation, slope, drainage density, mean annual rainfall, proximity to rivers, land use, land cover change, and soil type. The results indicated that ~ 51.4% (5,855,130.12 ha) of the basin is highly susceptible to flooding, while 40.6% (4,625,378.51 ha) is moderately prone, and 7.6% (866,358.09 ha) is at low risk. The study identified drainage density, elevation, and slope as crucial factors influencing flood vulnerability. Additionally, the total estimated soil loss in the Awash River Basin was found to be 31,049,739 tons per year, with a mean annual loss of 28.6 tons per hectare. This research pioneers the combined study of flood hazards and soil erosion in the study area, where such an integrated analysis has not been previously conducted. It contributes to enhanced flood management and environmental planning while aligning with the Sustainable Development Goals (SDG 13) regarding climate change mitigation and adaptation.

In the fight against soil erosion, Ethiopia has a formidable obstacle. The Awash River Basin issue is addressed in this paper. Soil loss and the sediment transport index (STI) in the Awash River Basin were predicted using GIS and the Universal Soil Loss Equation (USLE) Model. Using the Universal Soil Loss Equation (USLE) in conjunction with Geographic Information System (GIS) and remote sensing technologies, this study evaluates the spatial distribution and intensity of soil erosion in the basin. The result of annual average soil loss shows a significant range from 0–31,049,739 t/h/y after analyzing of various soil, DEM, topographical and meteorological data, obtained from USGS and EMA. The broader implications of this finding are highlights the significant capacity of land management potential in study area. The result of sediment transport index which computed based on flow accumulation and slope gradients, ranges from 0–247,097. The finding stipulates that considerable increment of soil loss and sedimentation in the study area, and promote for implementing reforestation and contour farming, to mitigate potential erosion’s impact. Hence, sustainable erosion mitigation strategies in the upper part of the basin should to be considered. Furthermore, this study emphasizes how important land use patterns, erodibility of soil, and erosivity of rainfall are associate in exacerbating of erosion. This information is significant for conservation and the development of sustainable agricultural frameworks. In portions of the study Basin that are prone to soil loss and sediment deposition, sustainable erosion management measures according to topography and current land use types are strongly recommended.

Alongside population expansion and global warming, land use land cover change (LULCC) is a vital component of environmental change on a worldwide scale. In many developing countries, the dynamics of land use and land cover are becoming increasingly noticeable, and the main causes of these dynamics are globalization, rapid economic development, and population augmentation. The primary cause of human-induced land use and land cover change, which primarily occurs in nations like Ethiopia, is rapid population increment. The study area, the Awash River Basin (ARB), has several serious problems, including growing population, urbanization, water resource scarcity, and land degradation. The dynamics and relationship between population growth, land-use, and land-cover change in the study area with respect to flood threats were to be examined in this study. LULCC imbalances were examined and comprehensive supervised land use classification maps were created using the geospatial techniques used in GIS and RS. In the same year, the 1990, 2000, 2010 and 2020 classifications had estimated overall accuracies of 94, 97.6, 99, and 96, with kappa coefficients of 0.92, 0.97, 0.99, and 0.95. In general, there was a 1.3% decrease in agricultural land over the three decades (1990–2020); however, there was a 50% decrease in bare land, a 43% decrease in deep water bodies, a 13.7% increase in forest cover, a 191% increase in the wetland category, and a 121% increase in urban area. The population is expected to expand by 8.638 million to 16.8 million between 1990 and 2020. The results of the Pearson correlation analysis showed that the bare land, deep water bodies, agricultural land, and forest coverage all had negative Pearson r figures (− 0.75, − 0.49, − 0.28, and − 0.25, respectively). On the other hand, both urban and wetland areas have favorable correlations with population growth (0.94 and 0.89, respectively). Furthermore, for 1990, 2000, 2010, and 2020, the corresponding annual estimated land consumption rate (LCR) was 0.29, 0.28, 0.26, and 0.34. Flooding may have resulted from changes in land use and land cover since then due to population growth and growing amounts of built-up land. In order to mitigate the effects of flooding and unanticipated rapid land use change, it is crucial to take into account nature-based solutions that are characterized as sustainable. Furthermore, this research helps to achieve the Sustainable Development Goals for 2030: Goal 15 involves investigating land use changes and conservation efforts to protect ecosystems and biodiversity.

Flood is the second major hazard in Ethiopia, next to drought. The reason behind this is the topography of highland mountains and lowland plains with natural drainage networks created by primary river lines. The study area, Awash River Basin nowadays, encounters several environmental challenges such as land degradation, high growth of population density, deterioration of natural water, wetland destruction, desertification, and salinity. Flooding is also the huge problem that can magnify how severe environmental degradation is in the Awash River Basin. Flood hazard mapping is a critical component of flood-prone land use planning and mitigation strategies. Various studies show that GIS-based flood hazard mapping is significant to hinder severe flood hazards. This paper was an attempt to produce a GIS-based flood hazard area map and discuss major causes and impacts of flooding in the Awash River basin. The main parameters used to produce maps were elevation, slope, drainage density, average annual rainfall, proximity to rivers, land use, land cover change, and soil types. Hence, the rasterized and reclassified potential flood-generating factors were weighted, and a pair-wise comparison had been made. As a result, the vast majority of the basin, or 5,855,130.12 ha (51.4%), is susceptible to high flood hazards, while 4,625,378.51 ha (40.6%) and 866,358.09 ha (7.6%) of the area covered are prone to moderate and low flood hazards, respectively. When compared to other factors, the drainage density, elevation, and slope level have a greater impact on the vulnerability to flood hazards. The outcomes of this research contribute to effective flood risk management and environmental planning strategies in the Awash River basin.