Examining the impact of Nkumba dumpsite on catchment water sources around Katabi town council, Wakiso district.

Abstract

Municipal solid waste management remains a very big challenge especially in the developing countries which mainly use land filling and dumpsites to manage solid waste. These techniques pose great threats to the environment as the resultant leachate from the decomposing waste migrates causing pollution to water, soil and air. Despite the introduction of Nkumba dumpsite at the fringes of Lake Victoria, a fragile ecosystem with several Ramsar sites and a biodiversity hotspot, there is a dearth of information regarding the waste being dumped and the impacts of the dumpsite to community. This study was conducted to: i) characterize the physical composition of solid waste dumped at Nkumba dumpsite, ii) assess the risk of surface water contamination due to leachate migration and iii) assess the socio-economic impacts of the dumpsite in the community. To achieve the set objectives, two trucks of the solid waste received at Nkumba dumpsite were randomly selected, emptied and the waste was segregated and weighed into different categories on every Tuesday and Thursday for eight days in November, 2021. Water and leachate samples were collected and analyzed from the Uganda Water Resources Institute laboratory, Entebbe while a survey was conducted to assess the socio-economic impacts arising from the dumpsite activities. Results showed that the waste dumped at Nkumba dump site is predominantly organic (66%) followed by glass (10.3%) and hard plastics (7%) while leachate predominantly comprised of Manganese (4.227±1.91 mg/L) and Zinc (0.399±0.309mg/L). The biological oxygen demand (87.38±21.65 mg/L), chemical oxygen demand (1260±430 mg/L), and electrical conductivity (10234±4921 μS/cm) were all above the recommended effluent discharge thresholds. Electrical conductivity, total dissolved solids, Manganese and Lead concentrations in leachate decreased significantly with distance from the dumpsite. The dumpsite served as a source of income, providing employment opportunities and resources like animal feeds and raw materials for craft making, hence enhancing households’ wellbeing. However, air pollution was evident through bad smells emitted especially in the rainy season. The findings imply that the dumpsite impacts on the community and environment both positively and negatively. It is therefore recommended that leachate from the dumpsite be treated before release into the lake catchment and Entebbe Municipal Council Authority should conduct timely water quality monitoring around the dumpsite to maintain ecosystem health and protect water users from exposure to contaminated water sources.