Evaluation of Salinity and Sodicity Hazards of Groundwater for Irrigation Suitability in Bharuch District, Gujarat, India

Abstract

This study evaluates the salinity and sodicity hazards of groundwater and their impact on irrigation suitability in Bharuch district, Gujarat. It was undertaken to assess groundwater quality for irrigation. The total of 210 samples were collected from seven talukas viz., Bharuch, Ankleshwar, Jhagadia, Hansot, Amod, Vagra, and Jambusar, during the months of March, April and May, 2024. EC values ranged from 0.34 to 4.29 dS m-1 with a mean of 1.53 dS m-1, indicating low to high salinity hazard. Based on USDA salinity classification, 12.9% samples fell under "C1" and "C2" (low to medium salinity), 64.8% under "C3" (high salinity), and 22.4% under "C4" (very high salinity). Electrical conductivity revealed moderate to very high salinity in a significant proportion of samples, posing potential long-term salinity risks in parts of Bharuch, Amod, and Vagra talukas. SAR values ranged from 0.11 to 17.42 with an overall mean of 3.27. Based on SAR classification, 84.8% samples belonged to "S1" (low sodium hazard), 13.8% to "S2" (medium), and only 1.4% to "S3" (high hazard). RSC values ranged from -5.17 to 8.95 me L-1, with a district-wide average of 1.13 me L-1. Out of 210 samples, 67.6% fell under "Safe" class (RSC <1.25), 14.8% under "Marginal" (1.25-2.5) and 17.6% under "Unsafe" class (>2.5).