Causes and implications of groundwater depletion in India: A review

Abstract

Abstract Groundwater plays a vital role in food security, water availability, and economic growth of more than 1.3 billion people in India. Notwithstanding the development of irrigation schemes based on surface water, groundwater remains a primary source of irrigation in large parts of the country. The Green revolution in the 1970s contributed considerably to increasing food production in India through the development of groundwater-based irrigation, which resulted in an expansion of irrigated area and a rapid rise in the number of electric and diesel pumps. A large part of the rain-fed area was converted to irrigated agriculture leading to growing multiple crops in a year with increased crop yields. While the expansion in groundwater-based irrigation helped meet the rising food demands of a large population of India, it has resulted in several environmental implications. Groundwater depletion in India has now become one of the most prominent challenges for food and water security. Both in-situ and satellite-based observations indicate a rapid decline in groundwater storage in north India. Both natural and anthropogenic factors cause groundwater depletion in India. Groundwater pumping for irrigation remains the primary driver of groundwater depletion, which can further affect food and water security in India under climate change. Both in-situ and satellite-based measurements have issues and uncertainty. Land surface hydrological models provide essential insights in understanding the groundwater storage variability; however, need improvements in the representation of complex processes related to climate-human interactions. Sustainable management of groundwater in India is vital for tackling growing challenges related to water availability. Here we discuss the challenges and opportunities related to the measurements and modelling of groundwater, groundwater recharge, cropping systems and irrigation efficiency, and social and policy reforms for sustainable groundwater management in India.