Integrated Hydrogeological and Hydrochemical Studies in an Agri-horticulture Intensive Watershed at Narkhed, Nagpur, Maharashtra and Pandhurna, Chindwara, Madhya Pradesh - A Case Study from Central India

Abstract

The present study is an attempt to investigate the impact of intensive agriculture and horticulture activities on the hydrogeological and hydrochemical regime in a watershed in Central India. The study area covers 137 km2 and the land use land cover (LULC) study shows that 39.72% area is agrihorticulture land, and 29.78% of the land is covered with other vegetation. Groundwater budgeting is aimed to estimate stage of groundwater development and to examine the contribution of different competing users (domestic, agriculture and industries) on groundwater usage. The groundwater budgeting results show that the stage of groundwater development is 100.26%, thus the study area falls under the over-exploited category as per GEC 2015 norms. The groundwater quality indicates the elevated concentration of nitrate (>45 mg/L) in 41% samples of pre-monsoon season and 80% samples in the post-monsoon season. The elevated concentration of nitrate in groundwater samples of the post-monsoon season indicates the contamination due to the non-point sources like excessive use of fertilizers in horti-agriculture. The sodium adsorption ratio (SAR) values indicate that groundwater is suitable for irrigation. However, physico-chemical water quality results show that 74% samples of pre-monsoon and 85% samples of the post-monsoon season are found unsuitable for drinking as compared to acceptable limits of drinking water specification BIS 10500:2012. The study area needs intervention measures both on the supply side and demand side to bring the development stage and water quality to safer limits. Long term mitigation strategies for the revival of the natural streams should also be adopted to increase water availability in the study area. Precision agriculture, promotion of organic farming, minimization of water use, soil amendments for soil moisture retention and prevention of the runoff must be included in the management practices to improve the health of the watershed and for the long term sustainability.