An Explorement of the Implications of Dumpsite Leachate on Surface Water Quality in Muenene River, Mutare, Zimbabwe

Background: Solid waste is one of biggest challenges of the urban areas of all sizes, from mega cities to small towns and large villages, which are home to the majority of mankind. In addition, the non-industrialised countries have low levels of refuse collection rates of 30 to 60% in low income countries and 50-60% in middle income countries. Globally, there are ongoing campaigns encouraging the use of the environment in a sustainable manner, which implies that the negative impacts on the environment and climate change must be taken into consideration. Methodology: The researchers instituted an experimental design. The researchers collected leachate samples from Mutare Open Dump site for laboratory analysis. Water samples were also collected from Muenene River for physico-chemical parameter analysis, heavy metal analysis and nutrient for laboratory analysis. The results were compared with the WHO standards and the Environmental Management Agency standards. The Winkler method was used for determination of Dissolved Oxygen, the multi-parameter brand 40HQD was used to test for the physico-chemical parameters [pH, Electrical conductivity (EC), and Total Dissolved Solids (TDS)]. Atomic Absorption Spectrometry (AAS) was used for the determination of iron, copper, zinc, cadmium, nickel, manganese, chromium, calcium, Magnesium and lead from samples The Spectrophotometer was used to measure the nutrients of phosphate, nitrates, sulphates, and ammonia. The broad objective of the study being to assess the impacts of dumpsite leachate in surface water quality in Muenene River in Mutare. The specific objectives were, to determine the levels and variations of the following physico-chemical parameters in Muenene River: pH, TDS, EC, and Salinity.to analyse the nutrient levels in leachate and leachate-contaminated Muenene River water in terms of nitrate, ammonia, sulphate, and phosphate and to measure the concentrations of selected heavy metals (Cd, Zn, Fe, Cr, Pb, Mg, Cu, and Ni) in Mutare dumpsite leachate. Results: Nutrients such as ammonia, phosphate, nitrates were found to be above the permissible levels, subsequently leading pollution of the Muenene River. The heavy metals include Fe, Pb, Mn and Cd were found to be above permissible levels in terms of S.I 6 of 2007 for wastewater discharge regulations in Zimbabwe. Zn, Ni and Cr were detected but were at normal range that is not harmful to the environment. The leachate generated from dump site finally flows into a stream used to irrigate vegetables and fruits. The water quality analysis revealed unsatisfactory results due to the elevated concentrations of phosphorus, ammonia, and the biochemical oxygen demand ratio (BOD). Conclusion: Results of the physico-chemical parameters analysis indicated that untreated leachate and unsegregated solid waste leads to deterioration of water quality. The nutrient quality of the water was also compromised as ammonia, phosphate, nitrates were found to be above the permissible. The heavy metals include Fe, Pb, Mn and Cd that were found to be above permissible levels in terms of S.I 6 of 2007 for wastewater discharge regulations in Zimbabwe. Zn, Ni and Cr were detected but were at normal range that is not harmful to the environment.