Current Status of Irrigation Systems in Tamil Nadu

Abstract

Tamil Nadu’s irrigation systems represent one of the most diversified and historically evolved water management structures in India, comprising canals, tanks (system and non-system), open wells and bore wells that together sustain the state’s predominantly agrarian economy. Based on data from the Season and Crop Report 2022–23 (Government of Tamil Nadu), the Dynamic Ground Water Resources Assessment Reports (Central Ground Water Board, 2020–2022), and the Sixth Minor Irrigation Census (Ministry of Jal Shakti), the present review highlights the structural composition, emerging trends and sustainability concerns of Tamil Nadu’s irrigation sector. The gross irrigated area during 2022–23 was around 29.20 lakh hectares, of which approximately 63% was irrigated by wells and bore wells, 23.4% by canals and 13.7% by tanks. Groundwater has become the principal source of irrigation, with an annual recharge estimated at 21.51 billion cubic metres (BCM) and extraction at 14.42 BCM—reflecting a stage of extraction of about 73.9%. Nearly 31% of the state’s groundwater assessment units are classified as over-exploited, showing serious stress in several delta and peri-urban regions. The Sixth Minor Irrigation Census (2017–18) reported a marginal increase in the total number of minor irrigation schemes (+2.05%), primarily due to growth in groundwater structures, while surface water systems showed a declining trend. These figures underscore a significant shift from traditional tank and canal irrigation toward groundwater dependence. The World Bank-supported Tamil Nadu Irrigated Agriculture Modernization Project (TNIAMP) has initiated modernization of irrigation infrastructure, tank rehabilitation and micro-irrigation expansion to address these challenges. However, persistent issues such as declining tank capacity, groundwater depletion and inefficient surface water conveyance continue to threaten sustainability. The paper concludes that future irrigation development in Tamil Nadu must emphasize conjunctive water use planning, revitalization of tank systems, promotion of water-saving technologies, stronger groundwater governance and real-time monitoring frameworks to ensure resilient and equitable irrigation management.