[01] Jean Adolphe Nkezabera, Faculty of Environmental Studies, University of Lay Adventists of Kigali (UNILAK), Kigali, Rwanda. [02] Narcisse Hakizimana, Faculty of Environmental Studies, University of Lay Adventists of Kigali (UNILAK), Kigali, Rwanda. [03] Eric Maniraho, Faculty of Environmental Studies, University of Lay Adventists of Kigali (UNILAK), Kigali, Rwanda. [04] Monique Buteto, Faculty of Environmental Studies, University of Lay Adventists of Kigali (UNILAK), Kigali, Rwanda. [05] Abias Maniragaba, Faculty of Environmental Studies, University of Lay Adventists of Kigali (UNILAK), Kigali, Rwanda.

Human activities, land forms and climate change made soil erosion challenges exists worldwide particularly in Rwanda as a big issue. Anthropogenic forces modify the feature landscape that caused significant soil erosion that has negative impact on surface water bodies. This study was conducted in order to identify most source of sediments to specify proper areas to government projects in Mwogo River protection in Nyamagabe and Huye Districts. Three sample sites with three parameters per site were taken by purposive method then evaluated through, Statistical Package for Social Sciences (SPSS). The results shown that Total Suspended Solids (TSS) and Turbidity were out of the acceptable range and Hydrogen potential (pH) was in acceptable range for natural potable water standards where the mean value on sites were PH 7.11, turbidity 4,301.33 NTU and TSS 1,327.66 mg/L. The short rainy season of 2020 and short dry season 2019 had very high correlation and significant impact on water quality where, r= 0.999 in range of 0.75 ≤ r< 1; very high and p value= 0.021; α=0.05 (p value<α) meant that soil erosion had significant impact in Mwogo River in succession years. The sources of sediments had different source and different in concentration, the study shown that Huye district was more polluter but dominantly in Rusuli marshland in Huye district with turbidity 6880 NTU and TSS 2280 mg/L turbidity 5080 NTU and TSS 1190 mg/L at outlet of Huye district than turbidity 944 NTU and TSS 513 mg/L at outlet of Nyamagabe district from soil erosion impacts. The results shown that development was not proportion to environmental protection leads to deterioration of Mwogo water body, which indicated the requirement of strengthening water resource management measures through restoration of wetland and watershed by land cover, buffer zone promotion and runoff decrease rate powerfully in Huye district.

Soil Erosion, Water Quality, Mwogo River, Huye District

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