Tamil Nadu is endowed with 3 per cent of the country’s water resources. It receives an annual rainfall of 925 mm. The state has 34 river basins divided into 17 major river basins and 127 sub-basins. Despite being a coastal state, Tamil Nadu is one of the most water-starved states in the country and has the highest percentage of drought-prone area relative to its total geographical area, at about 64 per cent. The per capita availability of water in the state is about 750 cubic metres per annum compared to the national average of 2,100 cubic metres.
Tamil Nadu has been facing severe water scarcity in many places and Chennai has been the worst affected. In fact, June 19, 2019 was declared as “Day Zero” in the city. Nevertheless, the state government has been taking the required steps to deal with the problem of water scarcity. By way of devising strategies and implementing a number of schemes and projects, the state government aims to address the issue of water shortages.
Pain points: Factors responsible for the water crisis
One of the key reasons behind the water shortage in Tamil Nadu is the rapid increase in urbanisation. Besides, a sharp fall in the groundwater level, reduction in the storage capacity of tanks, increasing conflicts between water using groups, disputes with neighbouring states related to water allocation and sharing, etc., have all been responsible for adding to the state’s water woes.
Tamil Nadu faces a water demand-supply gap of 2.25 million hectare-metres (m ha-m). The total water requirement from industry, households, livestock and irrigation stands at 7 m ha-m. However, the total supply (from both surface water and groundwater) stands at 5 m ha-m, a deficit of 2 m ha-m. Further, adding the water requirement for environmental protection and recreational activities (0.25 m h-ma) increases the demand-supply gap to 2.25 m ha-m.
The problem lies not only in the development of water resources, but also sustainable management of already developed resources. Misplaced and inappropriate policies leading to indiscriminate use of water, lack of appropriate technologies, poor technology transfer mechanisms, and inadequate institutional support systems have led to serious agro-ecological and sustainability problems. In addition, peripheral encroachment of waterbodies, shrinkage of river and water courses due to encroachment for infrastructure development, high levels of pollution in water resources, poor flood management, and destruction of the cascading topography of the river systems, among others, have added to the state’s water scarcity.
Water mission: Key initiatives to address water issues
To tackle the severe water scarcity and to ensure that a similar situation does not arise in the future, the Tamil Nadu government has embarked upon a water conservation mission with the aim of developing, conserving, protecting and managing its water resources. The key objectives of the mission are ensuring:
- Vibrant, revived and recharged waterbodies
- Assured, equitable and sustainable water for all
- Successful community-managed water supply
- Safe disposal of solid and liquid waste for a clean and healthy environment
- Cost-effective technology for sustainable management
- Formation of a common water regulatory authority for judicious use of water for all sectors
- Mitigation of the impact of climate change on water and food
- Improvement of sustainable irrigation services with a specific focus on the unreached
- Creation of a collective, shared understanding of water, development of an equitable and sustainable system of community collaborative water management
- Initiation and fostering of public-public partnerships amongst water and food organisations.
The state government aims to increase the gross irrigated area from 3.4-3.5 million hectares at present to 5 million hectares in another 7-10 years. The strategies that have been proposed for achieving the target are ensuring effective utilisation of flood waters and conjunctive use of surface water, groundwater and rain water; intensifying drip and sprinkler methods of irrigation; practising proven water management techniques like system of rice intensification for paddy, pair row method for all row crops etc.
In addition, the Tamil Nadu government has proposed a gamut of initiatives for improving water and irrigation management. The supply management initiatives include water harvesting; construction of more storage structures; interlinking of rivers; reclaiming brackish water, and sewage and industrial effluents for groundwater recharge and agricultural use; reclaiming the polluted land and water in the Palar, Bhavani and Noyyal river basins; desalination of seawater in coastal areas for drinking and industrial use; among others. The demand-side management initiatives involve increasing water use efficiency, introducing advanced methods of irrigation, increasing the productivity of unit quantity of water (more crop per drop), introducing changes in cropping patterns, managing groundwater (stabilising the water level for sustainability) and improving irrigation management. Meanwhile, the government has also adopted a multi-pronged approach for regeneration of natural resources.
Besides the initiatives being taken and strategies being devised for addressing the water problems, 18 schemes/projects are under implementation for increasing the overall water infrastructure capacity of the state. These projects are being implemented at a cost of Rs 118.72 billion. Key among these are the Tamil Nadu Irrigated Agriculture Modernisation Project (Rs 29.62 billion), the Athikadavu Avinashi pumping project (Rs 16.52 billion) and the Asian Development Bank-assisted Climate Change Adaptation Program in the Cauvery delta (Rs 15.6 billion).
Case study: IWARM project
The World Bank-funded multi disciplinary Irrigated Agriculture Modernisation and Waterbodies Restoration and Management (IWARM) project was implemented during 2007-12 by the Water Resources Organisation, the public works department and the Tamil Nadu government as nodal agencies. In terms of outreach, the project covered more than 24,000 hamlets, with about 5,000 irrigation tanks in 61 sub-basins. Besides, it benefited an area of approximately 0.67 million hectares of irrigated land. Some of the relevant outcomes of the project were reduction of water supply and demand gap (in terms of area) by 60.03 per cent, increase in fully irrigated area by 39 per cent, increase in productivity of various crops (23-40 per cent) and expansion of micro-irrigation in 47,922 hectares of land.
The key factors responsible for the success of the project were inter departmental convergence, political will, access to information, a comprehensive and integrated approach to planning water demand and management, community engagement, and strong institutions and systems at the local level to ensure equity and sustainability. With the necessary modifications, the approach and methodology adopted in the IWARM project can potentially be applied and upscaled across the country’s rain-fed areas.
In sum, the various initiatives taken by the Tamil Nadu government provided respite to the drought-stricken state. After undergoing one of the worst crises in its history, the state government has started to take initiatives to ensure water security in the long run. To achieve this objective, it has designed strategies to ensure integrated water resource management, river basin management, management at the sub-basin level and peaceful cooperation among the riparian states. In tandem, timely implementation of these initiatives and projects would be required to ensure that a similar situation does not arise again.
Based on a presentation by S. Sivalingam, Superintending Engineer, Water Resources Department, Government of Tamil Nadu, at a recent India Infrastructure conference