Irrigation Suitability Assessment of Groundwater in Upper Karha Drainage Basin

Abstract Groundwater serves as an essential source of water for household consumption, livestock, and agricultural irrigation. However, its quantity and quality are increasingly under pressure due to the expansion of irrigation, industrial growth, and rapid urban development (Lloyd & Heathcote, 1985; Raghunath, 1987). In many semi-arid parts of India, improper management of solid and liquid wastes, along with insufficient treatment and disposal systems, enables pollutants to infiltrate subsurface formations. This process leads to the degradation of groundwater quality and raises significant health concerns for communities that depend primarily on groundwater for drinking purposes (APHA, 1998; BIS, 2003). The present investigation focuses on assessing groundwater quality in the Upper Karha River Basin, situated in Purandar Tahasil , District Pune, Maharashtra State. This region represents the origin zone of the Karha River and has recently been facing issues related to groundwater depletion and declining water quality, largely as a result of excessive extraction and changes in land use patterns. A total of 30 groundwater samples were gathered and examined to assess their key physico-chemical properties as well as their suitability for irrigation purposes. he laboratory findings were subsequently integrated into a GIS framework to generate thematic maps illustrating the spatial variation of parameters such as pH, electrical conductivity (EC), sodium adsorption ratio (SAR), residual sodium carbonate (RSC), sodium percentage (Na%), and total dissolved solids (TDS) (APHA, 1998; Piper, 1953). These maps helped in identifying areas experiencing groundwater quality degradation, evaluating its appropriateness for irrigation use, and highlighting zones where over-reliance on groundwater may pose risks to sustainable water resource management in the basin.