[01] Lamek Nahayo, Faculty of Environmental Studies, University of Lay Adventists of Kigali, Kigali, Rwanda. [02] Christophe Mupenzi, Faculty of Environmental Studies, University of Lay Adventists of Kigali, Kigali, Rwanda. [03] Egide Kalisa, Faculty of Sciences, Auckland University of Technology, Auckland, New Zealand. [04] Valentine Mukanyandwi, Faculty of Environmental Studies, University of Lay Adventists of Kigali, Kigali, Rwanda. [05] Aboubakar Gasirabo, Faculty of Environmental Studies, University of Lay Adventists of Kigali, Kigali, Rwanda. [06] Egide Hakorimana, Faculty of Environmental Studies, University of Lay Adventists of Kigali, Kigali, Rwanda.

The rapid population growth, climate change and inappropriate natural resources use and management are predominantly limiting the community's access to safe drinking water. This record is high in poor regions compared to developed countries due to lack of awareness and/or financial capabilities. The objective of this study was to compare changes on drinking water quality during dry and rain seasons for the quality management and community wellness. The measured heavy metals were Calcium, Iron, Manganese, Copper, Aluminium and Zinc between July 2016 and February 2017 in the Eastern province of Rwanda. The samples were collected from three sites randomly selected among the water sources available in the study area. The monthly water samples were analysed in the laboratory of the water treatment plants neighbouring each sampling site. The results showed higher values of heavy metals during the rainy season than that in dry season. The mean of Manganese (0.25, 0.25 and 0.19 mg/L) at all sampling sites exceeded the drinking water guidelines (0.1 mg/L) of the World Health Organization. In addition, it was noted that the mean of Iron (0.35 mg/L) and Aluminium (0.95 mg/L) at Nyagatare site was higher than the WHO standards, 0.3 and 0.1 mg/L for the Iron and Aluminium, respectively. Thus, to ensure safe drinking water, it is good to initiate the rain harvest, agroforestry and bench terraces approaches to minimize the runoff, envisage appropriate wastes and wastewater management, and to approach and involve the community in managing water sources.

Drinking Water Quality, Heavy Metals, Water Sources, Eastern Rwanda

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