• Vinodh Kumar K N
• Raveesh H
• Nagesh P C
• Nagaraja D

Groundwater from deeper aquifers is a major source of freshwater in semi-arid regions of southern India. The Lower Papagni River Basin in Chikkaballapura district relies predominantly on groundwater for domestic, agricultural, and industrial needs due to declining surface water availability. This study evaluates the hydrochemical characteristics of deeper aquifers and assesses groundwater suitability using GIS-based spatial modelling. A total of 45 groundwater samples were collected from bore wells during pre- monsoon seasons. Hydrochemical parameters such as pH, EC, TDS, major cations (Ca²⁺, Mg²⁺, Na⁺, K⁺) and anions (HCO₃⁻, Cl⁻, SO₄²⁻, NO₃⁻, F⁻) were analysed following APHA standards. Analytical results were interpreted using Piper, Gibbs, Wilcox, USSL, and Spatial distribution maps were generated in GIS using inverse distance weighting (IDW) interpolation. Results reveal that groundwater is predominantly Ca–Mg–HCO₃ and Na–HCO₃ type, indicating rock–water interaction and silicate weathering as major controlling geochemical processes. EC and TDS values indicate moderate to high mineralization, with localized salinity zones. Fluoride concentrations exceed 1.5 mg/L in several pockets, marking them unsuitable for drinking. Irrigation indices (SAR, RSC, PI, KR) show that majority of samples fall under “good to permissible” class, though a few zones exhibit marginal suitability due to salinity hazards. Spatial maps highlight fluoride-rich and nitrate-rich clusters associated with granite-gneissic terrain and anthropogenic inputs. Overall, the groundwater from deeper aquifers is suitable to moderately suitable for irrigation, but requires treatment or blending for safe drinking use in affected regions. The study underscores the importance of continuous monitoring and GIS-based hydrochemical modelling for sustainable groundwater management.

Groundwater hydrochemistry, GIS-based groundwater quality assessment, Drinking water suitability, Irrigation water quality, Industrial water use.

"Hydrochemical Characteristics of Groundwater of Deeper Aquifers and GIS Based Assessment of Groundwater Quality for Domestic, Irrigational and Industrial Purposes in Lower Papagni River Basin, Chikkaballapura District, Karnataka.", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.13, Issue 2, page no.a365-a379, February-2026, Available :http://www.jetir.org/papers/JETIR2602051.pdf

"Hydrochemical Characteristics of Groundwater of Deeper Aquifers and GIS Based Assessment of Groundwater Quality for Domestic, Irrigational and Industrial Purposes in Lower Papagni River Basin, Chikkaballapura District, Karnataka.", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.13, Issue 2, page no. ppa365-a379, February-2026, Available at : http://www.jetir.org/papers/JETIR2602051.pdf