Water Resources

1. Water Resources State Mission guided by the National Water Mission • Undertake an integrated approach for conservation and management of water resources • Improve water use efficiency and control water pollution • Minimize wastage and ensure equitable distribution of water • Address the impacts of climate change on water resources.

2. Water Resources • Current Status • Institutional involved in Water Resource service delivery • Current Concerns • Current Policies, Programs and Projects • Likely implications of Climate Change on Water Resources • Strategies and to address Climate Change

3. Water Resources Current Status • More than 95 percent of the surface water and 80 percent of the Ground water is currently being used. • Agriculture is the largest consumer using 75 per cent of the water resources. • The state is highly dependent on monsoons the failure of which leads to severe scarcity of water and droughts • Surface Water-Cauvery is the major river basin, dependent on neighboring states for water supply • Ground Water-80 percent of ground water being used, non-uniform usage; most blocks are over exploited-Chennai • Storage Structures-85 reservoirs, need to create additional storage spaces and better management of existing ones, Water Resource Department attempting to revive them

4. Water Resources Institutional involved in Water Resource service delivery • Water Resources Department (WRD)-for planning, evolving, executing and maintaining the irrigation facilities and infrastructure of the State. • TWAD (Tamil Nadu Water Supply and Drainage Board)-for planning, implementation, maintenance, monitoring and surveillance of water schemes • Chennai Metropolitan Water Supply and Sewerage Board-for augmentation of water supply in the city • Rural Development and Panchayat Raj Department-for implementation of rural welfare schemes • Tamil Nadu Pollution Control Board (TNPCB)-for control, prevention and abatement of pollution in water resources • Educational Institutions-for research in hydrology and water resources management activities

5. Water Resources Current Concerns • Demand Supply Gap-sectoral demand is 2000 MCM more than the potential availability; gap expected to become 11 percent by 2020, 17 percent by 2050 • Over Exploitation of Ground water-80 percent of ground water currently in use; of the 385+1blocks • Floods-Copious rainfall in short duration-damage to infrastructure and life

6. Water Resources • Increase in North-East monsoon and decrease in South-West monsoon-N.E monsoon to increase from 34 to 63percent; S.W monsoon to decrease from 48 to 24 percent; need for distribution and diversion of water • Migration-from rural to urban thus increasing competition for water usage • Drought-drought prone state; ICAR states that frequency of droughts in Tamil Nadu would be 1 every 3 years • Low Water use Efficiency-due to lack of awareness

7. Water Resources Current Policies, Programs and Projects Policies and legislations related to water • The Water (Prevention and Control of Pollution) Act, 1974 • The Water (Prevention and Control of Pollution) Cess Act, 1977 • The Environment (Protection) Act 1986 • National Water Policy, 2002 On-going Programs and Projects • Master plan for artificial recharge • National Action Plan on Climate Change for Cauvery delta • Flood Management Program in Tamil Nadu • Dam Rehabilitation and Improvement Project (DRIP)

8. Water Resources Likely implications of Climate Change on Water Resources Rainfall projections • Annual rainfall to increase considerably by the end of century • Amount of rain to increase, the number of days of rainfall to decrease • Annual rainfall to increase 7-12mm/day • North East monsoon to increase considerably especially along the coast Ground water projections • Global warming to cause shifting of shorelines towards inland leading to severe salt water intrusion into ground water • Increased evaporation to effect reservoirs causing increased dependency on ground water

9. Water Resources Strategies Hilly Region • Undertaking rainwater-harvesting measures along the hill slopes, especially in the recharge zones • Constructing check dams, wherever feasible for the creation of water reservoirs for harnessing surface water • Increasing water storage capacity by repairing, renovating and restoring existing water bodies Coastal Region • Construct and rehabilitate of tail-end regulators to prevent the intrusion of saline water in channels • Install desalination water project in coastal areas to ensure availability of fresh water.

10. Water Resources • Control the volume of groundwater abstraction by strictly enforcing the ground water regulation acts to prevent seawater intrusion Plains • Increasing the reservoir storage potential of existing irrigation projects in the region. • Exploring the feasibility of transferring water from surplus basin to deficit basin • Limit rampant ground water extraction • Promote rainwater harvesting • Enhance Artificial Recharge in over exploited ground water areas • Improve Water use efficiency in agriculture • Redirect flood waters for groundwater recharge • Create small reservoir schemes such as check dams.

11. Water Resources Research • Develop food forecasting system • Assess water demand by sector by factoring in Climate change for short, medium and long term time lines • Undertake mapping of water resources in conjunction with land use and land classification Policy Related Interventions • Variable Irrigation Water Tax on surface and ground water use • Extend compulsory rain water harvesting regulation in individual houses in all towns and villages • Devise planning, monitoring and decision support systems for an integrated water management system in a climate change context

12. Water Resources • Modernization of Irrigation system using Drips, Sprinklers systems for improving water use efficiency • Introduce pricing regulation for use of piped water for domestic use and drinking water • Undertake periodical census of medium and minor irrigation projects to check sustainability and also to detect disfunctionalities and implement remedial measures