ANALYSIS OF SPATIOTEMPORAL VARIATION OF RIVER SOSIANI WATER QUALITY IN WESTERN KENYA

This study evaluates spatiotemporal variation in physiochemical properties of River Sosiani water in Eldoret, Kenya. River Sosiani is an essential supply of water for the residents and industrial activities in Eldoret town. Water Samples were collected in six sampling point along River Sosiani for a period of six months in dry and rainy season and analyzed in accordance with APHA water sampling and processing procedure. Data was managed and analyzed using Excel data analysis function. One way ANOVA and paired t-test analysis were used to determine statistically significant variation in physiochemical parameters along River Sosiani. River Sosiani exhibited spatial variation of all water quality parameters between the means for DO (P=1.20E-19), BOD (P=8.32E-83), Temperature (P=6.00E-13), EC (P=5.32E-14), TDS (P=3.18E-13), pH (P=1.15E-28), Nitrate-N (P=1.49E-33) and TP (P=1.06E-30). Seasonally, all parameters indicated significant temporal variation between the means for DO (P=5.66E-18), BOD (P=2.38E-03), Temperature (P=3.92E-11), EC (P=3.81E-10), TDS (P=1.31E-09), pH (P=1.35E-02), Nitrate-N (P=1.38E-13) and TP (P=6.72E-08). Some of the physiochemical parameters tested were within the recommended WASREB, NEMA and WHO permissible limits for drinking water. However, the study conclusively showed that the water quality of River Sosiani is deteriorated and hence unsuitable for human use. The study recommends urgent measures to conserve the catchment be undertaken and restoration of degraded river section to ensure sustained future provision of ecological services to riparian communities and enhance river’s biological integrity.