The aim of this study was to investigate the effectiveness of water hyacinth (Eichhornia crassipes) in remediating a polluted river. Triplicate samples were collected on three different points designated SR1, SR2 and SR3 along the Shagashe River. The course of the river stretching from SR1 to SR3 was covered by over 95% water hyacinth during the period of study. SR1 was located on the upper stream, SR2 centrally and SR3 furthest downstream. Analysis for electrical conductivity, total dissolved solids (TDS), sulphates, phosphates, total hardness, pH, nitrates, nitrites and total nitrogen on all samples was done. Statistical analysis was done to check if there was a significant reduction of the parameters moving downstream. The results indicate that water hyacinth was remediating the river as noted by the significant reduction of electrical conductivity (25% decrease), total dissolved solids (TDS) (26%), sulphates (45%), phosphates (33%) and total hardness (37%) between the sample points SR1 and SR3. Statistical analysis showed no significant changes for the other parameters.