Water Quality Assessment of River Tana

Drinking water with high concentrations of fluoride is of great concern in many parts of Kenya. Nonetheless, fluoride in small amounts is essential for bones and formation of dental enamel in both animals and humans. The aim of this research was to assess the content of some anions, cations, total suspended solids (TSS), total dissolved solids (TDS), pH and some heavy metals. Spectrophotometric method was used to measure chloride, sulphate, ammonium and nitrate. Ion selective electrode was used to measure fluoride, total dissolved solids and pH. Gravimetric method was used to measure total suspended solids. Atomic Absorption Spectrometer (AAS) was used to measure the content of cadmium and zinc. The results were as follows: Cd 0.009 mg/L; Zn 1.6 mg/L; F- 1.6 mg/L; pH 8.6; Cl- 41 mg/L; SO4 2- 145 mg/L; NH4 + 0.4; TDS 508 miS/cm; TSS 25mg/L; and NO3 - 11 mg/L. All these were lower than the NEMA guideline values except the levels of zinc, fluoride and nitrate and pH which were all above the NEMA guideline values. The values of zinc, fluoride and nitrate were marginally higher than the guideline values.