Hydro-Geochemical Investigation and Subsurface Water Quality Assessment of Tatti-Halla Basin, Yallapur, Uttarakannada District, Karnataka, India

In this study, subsurface water quality and hydro-geochemistry are examined in Tattihalla Basin in Yellapur, UttaraKannada district, Karnataka. A total of fifty surface and subsurface water samples were collected in 2023, both before and after the monsoon, and analyzed for a variety of physico-chemical characteristics. The results show that pH of the subsurface water in this region ranges from 6.8 to 8.4, suggesting an alkaline state. Ca2⁺ > Mg2⁺ > Na⁺ > K⁺ is the order of primary cat-ions. The principal hydro-chemical facies identified in the Piper trilinear diagram is Ca-Mg-HCO₃. Gibbs graph shows that the main source of dissolved ions is rock weathering. Water Quality Index calculations show that 75 percent of the samples are safe to consume. The study provides insightful information on the Hydro-geochemical processes influencing subsurface water chemistry and its appropriateness for various applications in this important agricultural area.