Rainy seasonal analysis of Physico-chemical parameters of Mukungwa River at NGARU point

Abstract— Water availability and quality are important factors that determine not only where people can live, but also the quality of life. The Mukungwa river is affected by rainy season especially at Ngaru point before discharge in Nyabarongo river, where its physico – chemical properties are seasonally changed. This may cause serious problems on all forms of life in the river. Objective of this work was to assess the impacts of rainy season on physico-chemical properties of Mukugwa River before discharging into Nyabarongo River at Ngaru. The parameters such as pH, temperature, turbidity, electric conductivity, total dissolved solids (TSS), phosphates, nitrates, and ammonium were monitored in three rainy seasons: April, 2012; October, 2012 and May, 2017 respectively. In this research, pH, temperature, electric conductivity were analyzed in situ using multifunction pH-meter and others parameters, were analyzed in laboratory using electrometric, volumetric, turbidity tube and colorimetric methods. The measured values for each parameter in three seasons were analyzed using MS Excel, and then compared to their international standards for surface water delivered by World Health Organization (WHO). The findings showed high variation of TSS (134mg/l, 178mg/l, and 582mg/l), turbidity (322NTU, 317NTU and 1560NTU) and ammonium (0.498mg/L, 0.536mg/L and 0.78mg/L) in three rainy seasons assessed. The quality of Mukungwa River needs prevention measures in order to control its pollution by erosion