ISSN 2360-7955
Abstract
Rapid population growth, urbanization, and increased consumption have exerted pressure on freshwater resources, particularly in urban areas. This study evaluated the chemical quality of water in the Nyakomisaro tributary of River Kuja, comparing upstream and downstream sections in Kisii town, Kenya, between February and May 2016. Water samples were analyzed for total alkalinity, copper, lead, zinc, phosphorus, total suspended solids (TSS), and nitrates using standard laboratory techniques and Atomic Absorption Spectrophotometry. Data analysis employed SPSS, with means compared using a T-test at a 95% confidence level (p ≤ 0.05). Results showed mean concentrations of 3.04 mg/L (TSS), 71.06 mg/L (total alkalinity), 3.79 mg/L (nitrates), 8.66 mg/L (phosphates), 0.24 mg/L (copper), and 0.15 mg/L (zinc), while lead was undetectable. All parameters were higher downstream, with significant differences observed between upstream and downstream values. Despite these variations, levels remained within the permissible limits set by the National Environmental Management Authority (NEMA) and the World Health Organization (WHO), indicating water suitability for consumption. The study recommends expanding piped water supply and enforcing wastewater treatment before disposal. These findings will support policy formulation and sustainable water resource management in Kisii County.
Keywords: Chemical parameters, Downstream, Tributary, Upstream, Nyakomisaro