Hydro-Geochemical Characteristics of Sawaga River, Malaybalay City, Bukidnon

The Sawaga River of Malaybalay serves as one of the major sources of water for drinking, irrigation, and industrial uses. However, this river system is severely threatened due to slash and burn farming, illegal logging, mining, and quarrying. In this context, this study was conducted to assess the hydro-geochemical characteristics of the Sawaga River to determine its degree of impairment and hydro-geological processes that may influence the water chemistry. Water samples were collected and analyzed for major cations and anions and other relevant physicochemical parameters. Geochemical modeling was also employed to reveal the mineral phases that may control water chemistry. Results show that the water chemistry of the river was mainly Mg-Cl type and undersaturated with respect to anhydrite, gypsum and halite. Moderately acidic pH, an elevated concentration of nitrate, and high TSS concentration were observed particularly along the agricultural and built-up areas of the river. This overall water quality of Sawaga River could be mainly attributed to the influence of land use and human activities along the river. Hence, regular monitoring should be implemented coupled with strict implementation of environmental laws that should be carried out by the city government of Malaybalay to protect and conserve this river system.

 

Keywords - Sawaga river, hydro geochemical assessment, land use, water quality, watershed management