Future irrigation expansion outweigh groundwater recharge gains from climate change in semi-arid India

Abstract

Simultaneous effects of future climate and irrigation intensification on surface and groundwater systems are not well understood. Efforts are needed to understand the future groundwater availability and associated surface flows under business-as-usual management to formulate policy changes to improve water sustainability. We combine measurements with integrated modeling (MIKE SHE/MIKE11) to evaluate the effects of future climate (2040-2069), with and without irrigation expansion, on water levels and flows in an agricultural watershed in low-storage crystalline aquifer region of south India. Demand and supply management changes, including improved efficiency of irrigation water as well as energy uses, were evaluated. Increased future rainfall (7-43%, from 5 Global Climate Models) with no further expansion of irrigation wells increased the groundwater recharge (10-55%); however, most of the recharge moved out of watershed as increased baseflow (17-154%) with a small increase in net recharge (+0.2mm/year). When increased rainfall was considered with projected increase in irrigation withdrawals, both hydrologic extremes of well drying and flooding were predicted. A 100-year flow event was predicted to be a 5-year event in the future. If irrigation expansion follows the historical trends, earlier and more frequent well drying, a source of farmers' distress in India, was predicted to worsen in the future despite the recharge gains from increased rainfall. Storage and use of excess flows, improved irrigation efficiency with flood to drip conversion in 25% of irrigated area, and reduced energy subsidy (free electricity for 3.5h compared to 7h/day; $1 billion savings) provided sufficient water savings to support future expansion in irrigated areas while mitigating well drying as well as flooding. Reductions in energy subsidy to fund the implementation of economically desirable (high benefit-cost ratio) demand (drip irrigation) and supply (water capture and storage) management was recommended to achieve a sustainable food-water-energy nexus in semi-arid regions.

Limited Demand or Unreliable Supply? A Bibliometric Review and Computational Text Analysis of Research on Energy Policy in India

“…Another set of terms refers to the policy process: policy-making, policy change, policy decision, policy reform, and policy process. Numerous scholars use the terms policymaking or policy change while highlighting the evidentiary value of their study for policy design [174][175][176]. For instance, Khosla, Dukkipati [177] propose multi-criteria decision analysis as a procedural tool for analytically rigorous, participative, and transparent policymaking.…”

Multi-Criteria Hydro-Economic Decision Tool for Rejuvenating Community Irrigation Tanks in Rural India

“…The second objective of the paper is to develop a hydro-economic methodology to scientifically evaluate the viability of a representative lift irrigation scheme based on IWRM's framework of efficiency, equity ecological sustainability, and resource user's participation [8]. Past studies on minor irrigation projects have employed the conventional benefit-cost analysis (BCA) tool to evaluate economic viability and equity considerations of alternative water allocation measures under a variety of climate-related uncertainty [36][37][38][39]. BCA tool has also been widely used in other fields of investment decisions, for instance, renewable energy resource projects [40][41][42] and transportation projects [43,44].…”

“…This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). ), Ashimane(44), Bommanalli(43), Bugadimane(41), Nagarakura(39), Kibbali(36), Golikoppa(35), Dalavaayi(35), Keshinamane(35), Halige (34), Keresara(33), Konkana(33), Manthaguli (30), Chowdi-2nd (29), Chowdi-1st (29), Kadave-1st (28), Beerala(27), Nidagod(27), Hakkimane-1st(27), Shindigere(26)Earth and Environment Department, Florida International University, MM Campus, Miami, FL 33199, USA; nchar042@fiu.edu 2 College of Fisheries, Mangalore 575002, India; rcbhat@gmail.com 3 Private Farmer, Bhairumbe, Sirsi 581405, Karnataka, India; krishnamhegde@gmail.com…”

Building climate resilience in degraded agricultural landscapes through water management: A case study of Bundelkhand region, Central India

“…Mekonnen and Hoekstra (2016) reported that globally about 4 billion people live under severe water scarce conditions for at least one month of the year; 3.3 billion for at least three months; and 1.8 billion for at least half a year. Climate change has also created more uncertainty in water availability, increased risk, and production and economic losses (Wiltshire et al, 2013;Mekonnen and Hoekstra, 2016;Singh et al, 2017;Sishodia et al, 2018;Malek et al, 2018;Lu et al, 2019;Aggarwal et al, 2019). As agriculture is the largest consumer of freshwater, its declining availability has a direct impact on food security, sustainability, and livelihoods for millions of rural households, especially in developing countries like India (Berchoux et al, 2019;Garg et al, 2020;Zarei et al, 2020).…”