Ground Water Quality Indices and Irrigation Suitability Assessment in Agricultural Regions of Coastal Andhra Pradesh, India

Abstract

Ground Water is the principle source of irrigation in the agricultural regions of coastal Andhra Pradesh, where water quality plays a crucial role in maintaining soil health and sustaining crop productivity. The intent of the present study was to assess and categories the irrigation water quality of Vadlamudi, Vejendla, Guntur, Vijayawada, Tenali and Chirala. Key physicochemical parameters, including pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Sodium Adsorption Ratio (SAR), Residual Sodium Carbonate (RSC), and Permeability Index (PI), were measured in Ground Water samples taken from bore wells and tube wells. Standard irrigation water quality rating systems pertaining to salinity and sodicity hazards were used to assess the impact of Ground Water for irrigation. The findings revealed that Ground Water quality in selected agricultural regions of coastal Andhra Pradesh is generally suitable for irrigation, with some outliers in coastal and intensively cultivated areas. Approximately 62.5% of samples belonged to the C3 salinity class, while sodium hazard was low, with over 90% of samples classified as S1 (low SAR). Most samples (78.1%) were safe based on RSC, and PI results suggested good to moderate soil permeability. The higher EC and TDS values recorded in coastal areas such as Chirala show the influence of seawater intrusion and salt deposition. Although overall groundwater suitability for irrigation remains acceptable, continuous use of saline water may adversely affect soil structure, nutrient availability, and crop productivity. Therefore, regular monitoring of groundwater quality, adoption of efficient irrigation practices, improved drainage management, and cultivation of salt-tolerant crops are essential for sustaining soil health and agricultural productivity in the region.