ASSESSMENT OF WATER PRODUCTIVITY AND DEVELOPMENT OF COUPLED SYSTEM DYNAMICS-HYDROLOGICAL MODELLING FRAMEWORK: A CASE STUDY OF GROUNDWATER DEPLETION IN SANGRUR, PUNJAB

Abstract

Development of efficient policies that can lead to sustainable management solutions require a comprehensive understanding of the interplay of socio-economic and physical processes. But the complexities of these interactions along with limited stakeholder participation, makes it difficult to incorporate the socio-economic aspect in a physical model. Thus, to address this challenge, the study presents a framework to amalgamate both socio-economic and hydrological aspects through coupling of a system dynamic and hydrological model to offer a holistic perspective. The study explores the case study of Sangrur district in the state of Punjab, which is facing the problem of severe groundwater shortages and falling water tables. The region witnessed a surge in agricultural productivity during the Green Revolution due to adoption of high-yield crop varieties and availability of electricity subsidies for groundwater pumping. While the revolution ensured food security of the country, it fueled unsustainable pumping leading to over-exploitation of precious groundwater resources. The study explores the synergy between the system dynamic model i.e., VENSIM to understand the role of agricultural electricity subsidies, cropping patterns, groundwater drawdowns and the hydrological model i.e., MODFLOW to graph the patterns of groundwater depletion in response to intensive pumping, helping to delineate the extent of aquifer depletion. The models are loosely coupled to exchange values of groundwater levels, abstractions and recharge, examining three scenarios to assess the impact of current and forthcoming policies. The “Status quo” scenario reflects the present conditions, while the “Supply side measures” scenario investigates policies concerning groundwater replenishment post-extraction. Conversely, the “Demand side measures” explores methods to reduce overall demand of water for irrigation to reduce the groundwater extraction. This participatory framework has the potential to revolutionize the policymaking strategies pertaining to sustainable water management, striking a balance between agricultural productivity and groundwater conservation, and offering a framework for addressing similar challenges in the future.