Political economy of the energy-groundwater nexus in India: exploring issues and assessing policy options

Abstract

Groundwater is now a major source of agricultural water supply in many parts of the world. The value of groundwater as a new source of supply is well known. However, its additional buffering or stabilization value is less appreciated and even less analysed. Knowledge on groundwater's stabilization value is advanced by developing and estimating an empirical model using the case of tank irrigation systems in Tamil Nadu, India. Unlike previous work, the model uses cross-sectional rather than time-series data. The results show that for the case-study region, the stabilization function added approximately 15% to supply value. Scenarios with surface water and electricity price were incorporated in the model. Increased surface-water supply and electricity price caused reduction in groundwater use but the percent of stabilization value of groundwater increased. The findings are used both to suggest improvements in tank irrigation systems and to further contextualize knowledge of groundwater's stabilization value

Detection of Irrigated Crops from Sentinel-1 and Sentinel-2 Data to Estimate Seasonal Groundwater Use in South India

“…Previous studies have shown the complex interaction of groundwater depletion and energy subsidies in India, since groundwater extraction relies heavily on electric pumping and free electricity for farmers [16]. In northwestern India, agricultural pumping leads to the long-term fall of water tables in deep alluvial aquifers [6][7][8], but the annual groundwater abstraction rate seems to be constrained by shortages of energy rather than groundwater [40].…”

“…This financial support changed the status of this water resource from an emergency supply, in case of surface water scarcity, to the main water source for irrigated crops [16]. To cope with the recurrent groundwater shortages associated with deficient monsoon rainfalls and overexploitation, farmers modulate their consumption by limiting the extent of irrigated areas.…”

The International Scale of the Groundwater Issue

“…And the scale of resource exploitation has accelerated in the last two decades. The number of tubewells was less than a million in 1980, jumped to 8 million in the mid-1990s, and exceeded 15 million by 2010 (Shah et al 2012). In addition to cheaper pumps and low well installation costs, electric power subsidies to farms have played a pivotal role in the phenomenal growth of tubewells and overexploitation of groundwater in 16 major states of India.…”

“…In addition to cheaper pumps and low well installation costs, electric power subsidies to farms have played a pivotal role in the phenomenal growth of tubewells and overexploitation of groundwater in 16 major states of India. The flat power tariff reduced the marginal cost of pumping groundwater to near zero (Shah et al 2012).…”

“…In California (United States), 19 % of all electrical energy produced is used for water-related conveyance and treatment (Navigant Consulting Inc. 2006)-nearly 2 % of all electrical energy in California is used for groundwater extraction through pumping (GEI Consultants/Navigant Consulting Inc 2010). Such energy requirements account also for significant contributions to greenhouse gas emissions, estimated as 0.6 % of China's emissions (Wang et al 2012) and 4-6 % of India's emissions (Shah et al 2012). These energy requirements increase with the distance the water must be lifted (depth to water) and decrease with pump efficiency.…”