CONTENTS Preface V PART A: IRRIGATION SYSTEMS 1 1. Introduction 3 1.1Introduction 3 1.2 Irrigation Potential of India 3 1.3 Crop Yield and Productivity 4 1.4 Advantages and Disadvantages of Irrigation 5 , . 1.5 Types of Irrigation Projects 6 1.6 Productive and Protective Works 7 Summary 8 Review Questions 8 2. Flow Irrigation 9 2.1Introduction 9 2.2 Definitions of Some Common Terms 9 2.3 Relation between Duty and Delta 12 2.3.1Factors Affecting Duty 14 2.3.2 Improving Duty 15 2.4 Area-Elevation and Capacity-Elevation Curves22 2.5 Flood- Absorbing Capacity of a Reservoir 23 2.6 Reservoir Storage Capacity to Meet the Monthly Uniform or Variable Demands 24 Summary 29 Review Questions 29 3. Tank Irrigation 33 3.1Introduction 33 3.2 Tank Project 34 3.3 Tanks in Series 35 3.4 Renovation of Existing Tanks 3.4.1Desilting of Tanks 40 3.4.2 Augmentation of Tank Capacity41 Summary 42 Revieiu Questions 42 Soil Moisture and Consumptive Use 45 4.1Introduction 45 4.2Equilibrium Points 45 4.2.1Soil Moisture Tension 47 4.2.2Depth of Effective Root Zone 47 4.2.3 When to Apply Irrigation Water? 47 4.3Depth of Watering to Increase the Soil Moisture 48 4.4Functions of Irrigation Water 52 4.5 FIR from Consumptive Use Data 52 4.5.1Blancy-Criddle Method 52 4.5.2 Evaporation Index Method 53 Summary 57 Review Questions 57 5.Lift Irrigation 61 5.1Introduction 61 5.2 Advantages of Lift Irrigation over Flow Irrigation 65 5.3 Tube Well Design and Irrigation 66 5.4Design of Tube Well 66 Summary 76 Review Questions 76 6.Sprinkler Irrigation 79 6.1Introduction 79 6.2 Uniformity Coefficient 80 6.3Design Factors for Sprinkler Irrigation System 83 6.4 Economics of Sprinkler Irrigation: A Case Study of Bore Wells Drilled in Karnataka 88 6.4.1Soil-Water-Plant Relationship 88 6.4.2Design of the Sprinkler Irrigation System 88 6.4.3 Economical Viability of Sprinkler Irrigation 93 Summary 95 Review Questions 95 7.Drip Irrigation and Principles of Soil and Water Conservation 97 7.1Introduction 97 7.2 Principles of Soil and Water Conservation 103 Summary 106 Review Questions 106 8.Flooding and Border Irrigation 109 8.1Introduction 109 8.2 Analysis of Time in Border-Strip Method 110 8.2.1Unit Stream 112 8.2.2 Check Flooding 114 8.2.3Basin Method 115 Summary 115 Review Questions 115 9. Furrow and Corrugation Irrigation 117 9.1 Introduction 117 9.2 Furrow Irrigation 117 9.3 Corrugation Method 119 Summary 120 Review Questions 120 10. Crop Rotation and Irrigation Assessment 123 10.1 Introduction 123 10.2 Rotation of Crops 123 10.3 Irrigation Assessment 124 10.4 Betterment Levy 126 Summary 125 Review Questions 126 11. Irrigation Water Quality 127 11.1Introduction 127 11.2 Quality of Irrigation Water 127 Summary 130 Review Questions 130 12. Saline and Alkaline Soils and Their Reclamation 133 12.1Introduction 133 12.2 Classification of Saline and Alkaline Soils 133 12.3 Salt Efflorescence and Water Logging 134 12.4 Soil Reclamation 135 Summary 140 Review Questions 140 13. Doctrine of Water Rights 143 13.1Introduction 143 13.2 Types of Riparian Rights 143 13.2.1Appropriative Rights 143 13.2.2 Prior-Appropriation Rights 144 13.2.3 Interstate River Disputes 144 13.3 Cauvery Water Dispute: A Case Study 144 Summary 147 Review Questions 147 14.Canal Lining 149 14.1Introduction 149 14.2 Purpose of Canal Lining 150 14.3 Lining Materials 150 14.4 Economics of Canal Lining 151 Summary153 Review Questions 153 15.Stable Channels in Alluvium and Channel Transitions 155 15.1Introduction 155 15.2 Kennedy's Theory 155 15.3 Lace/s Regime Theory 159 15.3.1Permanent Regime 160 15.3.2Bed Width/Depth Ratio 160 15.4 Channel Sections for Specific Requirement163 15.4.1Channel Transitions171 15.4.2 Flow around Bends 183 Summary 185 Review Questions 185 16.River Behavior and Training 189 16.1Introduction 189 16.2Braided and Meandering Channels 190 16.3 River Training: Objects and Methods 192 16.4 Guide Banks 194 16.5 Horizontal or Launching Aprons 194 16.6 Spurs or Groynes 197 16.6.1 Solid or Impermeable Groynes or Spurs198 16.6.2 Permeable Groynes or Spurs 198 Summary 199 Review Questions 199 17.Diversion Head Works 201 17.1Introduction 201 17.2 Selection of Site 201 17.3 Divide Wall 202 17.4Log Chute 204 17.5Navigation Lock 204 17.6 Afflux (Margirfel) Bunds 204 17.7 Head Regulator of Main Canal 205 17.8 Silt Exclusion at Diversion Head Works206 17.8.1Silt Excluders or Under-Tunnels 206 17.8.2 Still Pond System of Regulation206 17.8.3 Silt Ejectors (or Silt Extractors) 207 17.8.4 Types of Weirs 213 17.8.5 Design of Vertical Drop Weirs 214 17.8.6 Hanging Groynes 217 17.8.7 Falling Shutters 217 17.8.8 Design of Weirs on Permeable Foundations 218 17.8.9 Flownet Analysis 225 Summary 227 Review Questions 227 18. Dams and Reservoirs 233 18.1Introduction 233 18.2 Selection of Site for Reservoir 233 18.3 Choice of Dams 234 18.3.1Gravity Dams 234 18.3.2 Low and High Dams 238 18.3.3 Practical Profile of a Low Dam 239 18.4 Other Forces Acting on Dam 244 18.4.1Wave Pressure (Pw) 244 18.4.2 Ice Thrust 245 18.4.3 Silt Pressure CPS) 245 18.4.4 Force Due to Earthquake 246 1 8.4.5 Thermal Stresses 247 18.5 Factors of Safety of Gravity Dams 248 18.6 Construction of Gravity Dams 257 18.7 Control of Cracking in Concrete Dams 257 18.8 Theory of Arch Dams 259 18.8.1Thin Cylinder Theory 259 18.8.2 Thick Cylinder Theory 261 18.8.3 Elastic Arch Theory 262 18.8.4 Trial Load Analysis 262 18.8.5 Modal Studies 263 18.9 Earth Dams 264 18.9.1Criteria for the Safe Design of Earth Dam 268 18.9.2 Spillway for Earth Dams 269 18.9.3 Spillway Crest Gates 271 Summary 280 Review Questions 280 19. Multipurpose Reservoirs 289 19.1Introduction 289 19.2 Multipurpose Reservoir Operation 290 19.3 Water Resource Development 292 19.4 Interlinking of Rivers in India 296 Summary 298 Review Questions 298 20.Canal Systems 20.1Introduction 299 20.2 Alignment of Irrigation Canal 299 20.3 Head Regulator and Cross Regulator 305 20.3.1Regulating Notches 305 20.3.2 Canal Escapes 305 20.3.3 Tail Escapes 307 20.4 Irrigation Outlets 307 20.4.1Irrigation Outlet Requirements 307 20.4.2 Types of Outlets 308 20.5 Cross-Drainage Works 311 20.5.1Types of C.D. Works 311 20.5.2 Catch Drain 314 Summary 315 Review Questons 315 21. Environmental Aspects 317 21.1Introduction 317 21.2 Tehri Dam Project-A Case Study 317 21.2.1Seismic Activity 319 21.22 Siltation 319 21.2.3Submergence 320 21.2.4 Rehabilitation 320 21.2.5 Flora Fauna and Fishery 320 21.2.6 Analysis and Conclusion of Project 321 21.3 Are Dams Boon or Bane? 321 Summary 323 Reviw Questions 323 PART B: IRRIGATION STRUCTURES: DESIGN AND DRAWING 325 Plate 1.Reservoir Design 327 Plate 2.Low-Gravity Dam and Spillway 333 Plate 3.Hydraulic Energy Dissipaters and Model Studies 341 Plate 4.High-Gravity Dam 355 Plate 5.Arch Dam 363 Plate 6.Tank Bund 369 Plate 7.Seepage and Drainage of Earthen Bunds 375 Plate 8.Earth Dam 379 Plate 9.Rock-Fill Dam 385 Plate 10.Composite Dam 387 Plate 11.Buttress Dam 389 Plate 12, Tank Sluices 391 Plate 13, Tank Surplus Escape (Core Wall Type) 397 Plate 14. Tank Surplus Weir (Wing Wall Type) 403 Plate 15. Canal Sluice.. 409 Plate 16. Irrigation Outlet (Crump Type) 413 Plate 17. Canal in Gravelly Soil 415 Plate 18. Canal Regulator (Cross Regulator) 419 Plate 19. Canal Drops 425 Plate 20. Aqueduct ' 451 Plate 21. Siphon Aqueduct . 459 Plate 22. Barrage 465 Plate 23. Vertical Drop Weir 479 Plate 24. Bell's Guide Bunds 485 Plate 25. Canal Siphon 489 Plate 26. Super Passage . 497 Plate 27. Gomti Aqueduct-A Case Study 563 Model Question Papers 507 References , 515 Index 517