[01] Narcisse Hakizimana, Faculty of Environmental Studies, University of Lay Adventists of Kigali (UNILAK), Kigali, Rwanda. [02] Olive Nishimwe, Faculty of Environmental Studies, University of Lay Adventists of Kigali (UNILAK), Kigali, Rwanda. [03] Jean Adolphe Nkezabera, 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] Lamek Nahayo, Faculty of Environmental Studies, University of Lay Adventists of Kigali (UNILAK), Kigali, Rwanda.

This study aims to assess the impacts of floods on Nyabugogo river bed in Kigali City of Rwanda, East Africa. The employed secondary data were obtained through desk review, and the primary data were collected throughout site visit for the observations and surveys techniques to record the width and bottom elevations of Nyabugogo river. These data were obtained through topographic survey equipment at six selected stations on Nyabugogo river. The data were processed and analyzed by using the Statistical Package for Social Sciences (SPSS) and Microsoft Excel. The period of this study was basically two years between January 2019 and January 2021. The results showed that the impacts associated with floods on Nyabugogo river are the excessive river width from riverbanks sliding and bottom levels changes resulted from sediments deposition. It was noted that the changes in river width were between 1.980 m and 6.85 m, while the bottom river elevation was decreased at 0.62m at station 2 only. The maximum bottom level increase of 1.54 m was observed at station 5. Despite the fact that it might not be easy for the government to stop flooding at Nyabugogo river, it is good to replant bamboo trees and grasses in the areas that they are missing along Nyabugogo river to protect soil erosion and river bank sliding. Placing the gabions at some locations of Nyabugogo river reaches is required in order create a good river landscape in Kigali City. Also, it is suggested to prepare and provide training and awareness programs on environmental matters on surrounding residents. This would help to reduce discharge household wastes in Nyabugogo river and its effluents in order to minimize bottom rivers sediments deposit which results in excessive floods. Finally, respect and protect buffer-zone along Nyabugogo river to enhance soil resistance to flood. The long-term solution should be to educate children and young people the course of waste management at schools as a solution to environmental pollution.

Impact, Floods, Nyabugogo River, Kigali City, Rwanda

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