OPTIMUM USE OF WATER RESOURCES

1. Introduction 2. Description of the Varamin Plain 2.1 Location and extent 2.2 Geomorphology 2.3 Geology 2.4 Land resources 2.5 Climate 2.6 Surface water resources 2.6.1 Selecting a discharge distribution 2.7. Groundwater resources 2.7.1 Groundwater in storage and present recovery 2.7.2 Groundwater quality 2.8 Present system of irrigation water supply 3. Digital groundwater basin model 3.1 Systems approach 3.2 Simulation 3.3 Groundwater basin modelling 3.4 Mathematical background 3.5 Developing an asymmetric grid 3.6 Digital computer solution 3.7 Varamin groundwater simulation model 3.7.1 Construction of nodal network 3.7.2 Preparation of data Transmissivity. Storage coefficient. Water table data. Dverall groundwater balance. Polygonal net deep percolation. Ground surface elevation. Elevation of the impervious base. Elevation of the impervious base at the mid-point of the flow path. Elevation of the drainage base 3.7.3 Calibration of the model 4. Agricultural planning 4.1 The model 4.2 Results 4.3 Conclusions 4.4 Subregional agricultural production patterns. 5. Developing a linear programming test model 5.1 The test model 5.2 Results obtained from the test model 6. Developing the comprehensive linear programming model 6.1 Objective 6.2 Activities 6.3Constraints 7. Calculating costs of activities 7.1 Polygonal costs of agricultural production 7.2 Polygon cost of surface water 7.3 Polygonal cost of well water 8. Calculating resource constraints and coefficients 8.1 Surface water constraints 8.2 Groundwater constraints 8.3 Maximum water demand of the polygons 8.4 Conveyance and field irrigation losses 8.4.1 Conveyance losses in main canals and laterals 8.4.2 Percolation losses downstream of farm group inlet 8.5 Linear programming matrix 9. Procedure in using the models 9.1 Determining the maximum river discharge 9.2 Determining the maximum groundwater abstraction 9.3 Selecting a land-use policy 9.4 Schematic of the computer studies 10. Results obtained from the modelling studies 10.1 Water supply scheme No.1 10.1.1 Optimal solution 10.1.2 Testing the optimal solution for its technical feasibility 10.1.3 Cost of water supply 10.1.4 Shadow prices of the used constraints 10.1.5 The water supply solution and land allocation policies 10.1.6 Economic consequences of the hydrological adjustments 10.1.7 Summary. 10.2 Water supply scheme No.2 10.2.1 Solution 10.2.2 Testing the solution for its technical feasibility 10.2.3 Cost of water supply 10.3 Water supply scheme No.3 10.3.1 Simulating river flow cycles 10.4 Water supply scheme No.4 10.4.1 Simulating artificial recharge 10.5Water supply scheme No.5 10.5.1 Solution 10.6 Water supply scheme No.6 10.6.1 Solution 10.7 Water supply scheme No.7 10.7.1 Solution 10.8 Water supply scheme No.8 10.8.1 Simulating river flow cycles 10.9 Water supply scheme No.9 10.9.1 Optimal solution 10.9.2 Testing the optimal solution for its technical feasibility 10.9.3 Adjusted solution 10.9.4 Cost of water supply 10.9.5 The water supply solution and the irrigated area 10.9.6 Shadow prices of farmers in the different polygons 10.9.7 Economic consequences of the hydrological adjustments 10.9.8 Summary 10.10 Water supply scheme No.10 10.10.1 Solution 10.10.2 Testing the solution for its technical feasibility 10.11 Water supply scheme No.11 10.11.1 Simulating river flow cycles 10.12 Water supply scheme No.12 10.12.1 Simulating artificial recharge 10.13 Parametric programming 10.13.1 Schemes Nos.13 to 17 II. Adjusting the water supply solutions to overcome monthly river discharge deficiencies 12. Discussion 12.1 Strong and weak points of the applied techniques 12.2 Comparison of the feasible solutions obtained 12.3 The models as tools for further planning.

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