MONITORING OF WATER-QUALITY IN UPPER MUKUVISI RIVER IN HARARE, ZIMBABWE

The impact of discharges from a fertilizer plant on the quality of the upper Mukuvisi River water was studied between the months of January 1989 and September 1990. Samples were collected at a point upstream from the effluent canal from the fertilizer plant, immediately downstream from the fertilizer plant and about 3 km downstream of the fertilizer plant. The water quality parameters which were monitored were temperature, pH, suspended solids, dissolved solids, conductivity, biological oxygen demand, dissolved oxygen, nitrates, phosphates, chlorides, potassium, calcium, Cu(II), Zn(II), Pb(II), Co(III), Ni(II), Cr(III), and Cr(VI). Pollution of the river waters by the fertilizer plant is evidenced by an increase in the levels of DS, NO3-, P-PO43-, Cl-, K, Ca, Cu, Fe, Zn, Pb, Co, and Cr, a drop in pH, and an increase in conductivity as the river transcended past the plant.