Enviromental Impact Evaluation Tools for River Engineering Projects in Sudan Case Study of Rosaries Dam

The objectives of this study is to estimate the reduction of Rosaries reservoir capacity, due to increase of sedimentation rate in the Dam as a result of soil erosion, beside decline in vegetation cover as a result of soil extended mechanized irrigation. The environmental impact assessment is the tool of analysis, using geographical information system and remote sensing techniques to identify the Land covers classes and forest decline. The result of the study showed continuous decrease of the capacity of the dam, as the sediment amount accelerate annually, due to vegetation cover removal and consequently soil erosion. A number of conclusions and recommendation stated to improve the environmental Condition through some necessary technical measures and some remedies to reduce the negative effects of the soil erosion processes