1. INTEGRATED WATER MANAGEMENT FOR FOOD AND ENVIRONMENT: THE CASE OF GHAGGAR –YAMUNA PLAIN NARENDRA KUMAR TYAGI NARENDRA KUMAR TYAGI 6: AGRO INDUSTRIES AND WATER

2. M AJOR PROBLEMS IN G HAGGAR - Y AMUNA B ASIN : Inadequate canal water supply. Excessive ground water withdrawal leading to steep fall in ground water table in freshwater zone. Low environmental flows during non monsoon period. Rise in groundwater table in poor water quality zones leading to increase in waterlogged areas and reduction in land productivity.

3. P ROPOSED C ONCEPT OF IWM The proposed model of IWM, revolves around enhancing water availability through : 1. Increased stream-aquifer interaction 2. Rain water conservation within cropping areas, 3. Conjunctive use of waters for facilitating brackish water use generated by sub-surface drainage system 4. Improved irrigation efficiency though production system mechanization.

4. IWM PROTOCOL FOR G HAGGAR -Y AMUNA BASIN Water harvesting in rice fields Improvement in on-farm water management Reallocation of crop areas Saline water disposal through network of sub surface drainage system to Yamuna river Developed IWM protocol of Ghaggar Yamuna basin Conjunctive use of fresh and marginal quality water

5. M ULTIPLE BENEFITS OF RAINWATER HARVESTING IN RICE PADDIES  Rainwater up to 150 mm could be stored in rice paddies without any damage to crop.  Reduced irrigation requirements by about 250 mm and increased green water availability.  Increased aquifer recharge Reduced of ground water pumping cost & carbon emission.  Down sizing of surface drainage network due to reduced runoff

6. I NCREASED S TREAM -A QUIFER I NTERACTION (SAI) D ISCRETIZED FINITE DIFFERENCE CELLS FOR APPLICATION I N STEADY STATE HYDRAULIC OPTIMIZATION MODEL IN LGB

7. O PTIMIZED GROUNDWATER YIELD THROUGH E NHANCED S TREAM -A QUIFER I NTERACTION (SAI)  Optimized pumping rates varied from 0.25 m 3 s- 1 to 8.48 m 3 s- 1, the values, particularly in river cells being several times higher as compared to the existing pumping rates.  The total SAI was of the order of 26.10 m 3 s -1 as compared to existing SAI of 16.2 m 3 s -1.  The model generated total maximized pumping is 44.1m 3 s -1.The optimized pumping induced about 60 % additional flow from stream to the aquifer

8. SALINE WATER USE FOR INCREASING SUPPLY AND REDUCING WATER LOGGING (S UB SURFACE DRAINAGE AND CONJUNCTIVE USE )  The marginal quality water can increase supply by 25-40 % in different parts of the plain.  Quality of saline drainage effluents improves with time and can be conjunctively used for irrigation.  Distribution of monsoon rainfall, seasonal root zone salinity,variation and long term aquifer salinity balance are important considerations.

9. M ECHANIZATION FOR I MPROVED I RRIGATED F ARMING Sustainable intensified irrigated agriculture needs rapid farm mechanization. Some progress made in adoption of zero or minimum tillage and laser land levelling. Adoption of MIS is at low level, but its market potential is very high Reallocation of water and diversified cropping is needed for out –scaling of MIS

10. P OTENTIAL E FFICIENCY OF A LTERNATIVE I RRIGATION S YSTEMS Efficiency, % 20 40 60 80 100 0 Modernized surface system Sprinkler system Bubbler and splitters Drip irrigation Laser LevellingZero Tillage Furrow Irrigation Raised bed planting

11. R ELATIVE COST (RCT) OF GENERATING ADDITIONAL WATER THROUGH SOME AGRICULTURAL WATER DEMAND MANAGEMENT TECHNOLOGIES

12. In IWM scheme,green water availability and its utilization in rice paddies is increased. Rice paddies also function as effective ground water recharge basins. On a limited scale,the potential SAI for augmenting water supply is indicated Horizontal subsurface drainage, together with conjunctive use of saline effluents help achieve multiple objectives- lowering of water table, generating water for irrigation, reducing root zone salinity and creating space for storing fresh water in root zone. It is however necessary to maintain balance between effluent use and its disposal for salt balance In IWM scheme,green water availability and its utilization in rice paddies is increased. Rice paddies also function as effective ground water recharge basins. On a limited scale,the potential SAI for augmenting water supply is indicated Horizontal subsurface drainage, together with conjunctive use of saline effluents help achieve multiple objectives- lowering of water table, generating water for irrigation, reducing root zone salinity and creating space for storing fresh water in root zone. It is however necessary to maintain balance between effluent use and its disposal for salt balance Summary Contd….

13.  Per unit land, water and energy productivity enhancement is possible only through mechanization of agriculture production system. It will create demand for more energy,but the intensity of energy use per unit product/income generated would decrease.  Finally, based on scientific investigations, the potential of IWM as a practical tool to maintain high agricultural productivity without invoking adverse environmental impacts on sub basin scale, has to an extent, been established.