WATER POWER ENGINEERING
CHAPTER 1 INTRODUCTION 1 11 Definition 1 12 Necessity of Irrigation 1 13 Total Planning Concept of Irrigation Project—scope of Irrigation Engineering 2 14 Benefits of Irrigation 4 15 ILL-Effects of Irrigation 6 16 History of Irrigation Development in India 7 17 Types of Irrigation Sysytems 8 Review Questions 10 CHAPTER 2 METHOD OF IRRIGATION 11 21 Classification of Irrigation Methods 11 22 Factors Affecting the Choice of the Method of Irrigation 11 23 Surface Irrigation Methods 12 231 Uncontrolled or Wild Flooding 13 232 Controlled Flooding 13 233 Flooding from Field Channels 13 234 Border Strip Method 15 235 Design of Border Strip Irrigation 18 236 Check Basin Method 21 237 Ring Basin Method 24 238 Furrow Method or Furrow Irrigation 25 24 Sprinkler Irrigation Method 31 25 Sub-Irrigation Methods or Sub-Surface Irrigation Methods 35 Solved Illustrative Examples 41 Review Questions 51 CHAPTER 3 SOIL WATER AND PLANT RELATIONSHIP 52 31 Introduction 52 32 Composition of Soil, Soil Texture and Soil Structure 53 33 Water Holding Capacity of Soil 54 Contents 34 Soil Groups of India 55 341 Alluvial Soils 55 342 Black Soils 55 343 Red Soils 56 344 Laterite Soils and Forest Soils 56 345 Desert Soils 56 346 Saline and Alkali Soils 56 35 Classification of soil water 56 351 Gravitational Water 57 352 Capillary Water 58 353 Hygroscopic Water 58 36 Soil Moisture tension 59 361 Soil Moisture Stress 59 37 Soil Moistyre Constants 59 371 Saturation Capacity 59 372 Field Capacity 60 373 Moisture Equivalent 60 374 One-third Atmosphere Moisture Point 61 378 Permanent Wilting Point 61 379 Temporary Wilting 62 3710 Ultimate Wilting 62 3711 Available Moisture 62 3712 Readily Available Moisture 62 38 Depth of Water (Or Moisture) Held by Soil In Root Zone and Available to Plants 63 39 Extraction Pattern of Soil Moisture in Root Zone by Plant Roots 64 310 Elements Essential For Plant Growth 64 311 Non-Essential Elements of Interest in Plant Nutrition 65 312 Maintaining Soil Fertility 66 3121 By Keeping the Land Fallow 66 3122 Addition of Manure and Fertilizers 66 3123 Crop Rotation 66 3124 Mixed or Inter-cropping 67 313 Quality of Irrigation Water 67 3131 Effect of Silt 67 3132 Effect of Salts 67 3133 Classification of Irrigation Water 72 3134 Improving the Quality of Irrigation Water 72 314 Saline, Saine-Alkai and Alkali (or Non-Saline Alkali) Sois 72 3141 Saline Soils 73 3142 Saline-Alkali Soils 74 3143 Alkali (or Non-saline Alkali) Soils 74 Solved Illustrative Examples 74 Review Questions 79 CHAPTER 4 WATER REQUIREMENTS OF CROPS 80 41 Introduction 80 42 Limiting Soil Moisture Conditions 80 43 Depth of Water Applied During Irrigation and Frequency of Irrigation 81 44 Crop Seasons and Crops of India 82 45 Crop Period and Base Period 82 46 Duty of Water and Delta 83 47 Factors Affecting Duty of Water 86 48 Methods of Improving Duty of Water 88 49 Commanded Areas and Intensity of Irrigation 89 491 Gross Commanded Area (GCA) 89 492 Culturable Commanded Area (CCA) 89 493 Intensity of Irrigation 90 410 Other Terms Related to Water Requirements of Crops 90 4101 Paleo Irrigation (or Paleo) 90 4102 Kor Watering, Kor Depth and Kor Period 90 4103 Outlet Factor 91 4104 Capacity Factor 91 4105 Time Factor 91 4106 Cumec Day 92 4107 Crop Ratio 92 4108 Overlap Allowance 92 411 Consumptive Use of Water-Evapotranspiration 92 4111 Potential Evapotranspiration (PET) and Actual Evapotranspiration (AET) 93 412 Irrigation Efficiencies 117 413 Irrigation Requirements of Crops 119 415 Assessment of Irrigation Water Charges 125 Solved Illustrative Examples 127 Review Questions 153 CHAPTER 5 HYDROLOGY 156 51 Definition 156 52 Hydrologic Cycle 156 53 Precipitation 157 531 Mechanism of Precipitation 157 532 Types of Precipitation 158 54 Measurement of Precipitation 159 55 Mean Annual Rainfall, Minimum and Maximum Annual Rainfall 168 56 Average Depth of Rainfall over an Area 169 57 Evaporation, Transpiration and Evapotranspiration 171 58 Infiltration 172 59 Runoff 174 510 Factors Affecting Runoff 175 511 Methods of Determination of Runoff 176 512 Estimation of Maximum or Peak Flood Discharge 181 513 Hydrograph 188 514 Unit Hydrograph 191 515 S-Hydrograph (or S-Curve) 193 516 Derivation of Unit Hydrographt of Different Unit Duration from a Unit Hydrograph of given Unit Duration 196 517 Derivation of Unit Hydrograph from Complex Storms 200 518 Synthetic Unit Hydrograph 201 Solved Illustrative Examples 205 Review Questions 226 CHAPTER 6 GROWUNDWATER HYDROLOGY 230 61 Introduction 230 62 Aquifer, Aquiclude, Aquifuge and Aquitard 231 63 Porosity, Specific Yield and Specific Retention 231 64 Divisions of Subsurface Water 232 65 Type of Aquifers 234 66 Groundwater Movement–Darcy’s Law 237 67 Storage Coefficient or storativity, Coefficient of Permeability or Hydraulic Conductivity and Coefficient of Transmissibility or Transmissivity 239 68 Well Hydraulics 242 69 Determination of Hydraulic Properties of Aquifer 249 610 Well Losses, Specific Capacity of Well and Well Efficiency 251 611 Interference Among Wells 253 612 Artesian Gravity Well 255 613 Partially Penetrating Wells 256 614 Spherical Flow in a Well 257 615 Unsteady Flow Towards Wells 259 616 Pumping Test Methods and Recovery Test Method 263 617 Types of Water Wells 270 618 Methods of Construction of Open Wells 277 619 Yield of an Open Well 278 620 Methods of Construction of Tube Wells 282 621 Well Shrouding and Well Development 290 622 Collector or Radial Wells 293 623 Other Sources of GrounDwater 294 Solved Illustrative Examples 295 Review Questions 319 CHAPTER 7 RESERVIOR PLANNING 321 71 Introduction 321 72 Types of Reservoirs 321 73 Investigations for Reservoir Planning 323 74 Selection of Site for a Reservoir 326 75 Zones of Storage in a Reservoir 326 76 Reservior Yield 328 77 Mass Curve and Demand Curve 329 78 Determination of Reservoir Capacity Required for a Specified Yield or Demand Using Mass Curve 330 79 Determination of Yield from a Reservoir of given Capacity 333 710 Demand Patterns for Various Types of Reservoirs 334 711 Apportionment of Total Cost of a Multi-Purpose Reservoir 336 712 Flood Routing 338 713 Reservoir Losses 343 714 Measures to Reduce Evaporation Loss in Reservoirs 345 715 Sediment Transport by Rivers-Reservoir Sedimentation 345 716 Control of Sedimentation of Reservoirs 349 Solved Illustrative Examples 350 Review Questions 365 CHAPTER 8 DAMS—GENERAL 367 81 Definition 367 82 Classification of Dams 367 821 Classification Based on Function 367 822 Classification based on Hydraulic Design 368 823 Classification based on Material of Construction 368 824 Classification based on Structural Behaviour 369 825 Classification based on Size 369 83 Factors Governing Selection of Type of Dam 369 84 Selection of Site for a Dam 372 85 Preliminary and Final Investigations of Dam Sites 373 86 Salient Features of Important Dams of India 375 Review Questions 378 CHAPTER 9 DESIGN AND CONSTRUCTION OF GRAVITY DAMS 379 91 Introduction 379 92 Forces Acting on a Gravity Dam 380 93 Load Combinations for Design 403 94 Reaction of Foundation and Distribution of Vertical (Or Normal Stress at the Base of Dam-Middle Third Rule 404 95 Principal and Shear Stress 406 96 Modes of Failure of Dam —Stability Requirements 409 97 Quality and Strength of Concrete and Masonry 414 98 Elementary Profile of a Gravity Dam 415 99 Pracrical Profile of a Gravity Dam 419 910 Methods of Design of Gravity Dams 423 911 Joints, Keys and Water Stops 429 912 Openings in Dams 434 913 Galleries 435 914 Adits, vaults and Shafts 436 915 Temperature Control in Concrete Dams 437 916 Foundation Treatment 438 Solved Illustrative Examples 440 Review Questions 464 CHAPTER 10 BUTTRESS AND ARCH DAMS 468 101 Introduction 468 102 Buttress Dams 468 103 Types of Buttress Dams 468 104 Forces on Buttress Dams 477 105 Design of Flat-Slab Type Buttress Dams 477 106 Advantages and Disadvanrages of Buttress Dams 486 107 Arch Dams 487 108 Types of Arch Dams 488 109 Forces on an Arch Dam 491 1010 Design of Arch Dams 492 Review Questions 498 CHAPTER 11 EMBANKMENT DAMS 499 111 Introduction 499 112 Types of Earth Dams 500 1121 Rolled Fill Dam 500 1122 Hydraulic Fill Dam 500 1133 Semi-hydraulic Fill Dam 500 113 Foundations for Earth Dams 503 114 Design of Earth Dams 504 115 Causes of Failures of Earth Dams 506 116 Criteria for Safe Design of Earth Dams 511 117 Safety Against Overtopping 511 118 Determination of Seepage Line 511 119 Characteristics of Seepafge Line 521 1110 Seepage Line Where Vertical And Horizontal Permeability Differ 522 1111 Flow Net 522 1112 Stability of Side Slopes of Earth Dam—Stability Analysis 525 1113 Stability of Earth Dam Against Horizontal Shear Developed At The Base of The Dam 537 1114 Stability of Foundation of an Earth Dam Against Horizontal Shear 543 1115 Check for Free Passage of Water Through Earth Dams 546 1116 Safety Against Piping 548 1117 Protection of Upstrem Slope of an Earth Dam 548 1118 Protection of Downstream Slope of an Earth Dam 549 1119 Measures to Control Seepage Through Earth Dams and Their Foundations 550 1120 Typical Cross-Sections of Earth Dams 568 1121 Design Considerations in Earthquake Regions 570 1122 Rockfill Dams 574 Solved Illustrative Examples 578 Review Questions 589 CHAPTER 12 SPILLWAYS, ENERGY DISSIPATORS, SPILLWAY GATES AND OUTLET WORKS 591 121 Introduction 591 122 Essential Requirements of a Spillway 591 123 Spillway Capacity 591 124 Components of Spillway 592 125 Types of Spillways 593 126 Free Overfall or Straight Drop Spillway 595 127 Overflow or Ogee Spillway 596 128 Chute or Open Channel or Trough Spillway 605 129 Side Channel Spillway 609 1210 Shaft or Morning Glory Spillway 614 1211 Conduit or Tunnel Spillway 617 1212 Siphon Spillway 617 1213 Energy Disspations Below Spillway —Scour Protection Below Spillway 631 1214 Stilling Basins 638 1215 Bucket Type Energy Dissipators 642 1216 Spillway Crest Gates 644 1217 Outlet Works 651 Review Questions 654 CHAPTER 13 DIVERSION HEADWORKS 656 131 Introduction 656 132 Types of Diversion Headworks 656 133 Location of Canal Headworks 657 134 Components of Diversion Headworks 659 135 Weir 659 136 Barrage 661 137 Effect of Construction of a Weir on the River Regime 661 138 Cause of Failure of Weirs on Permeable Foundation and Their Remedies 662 139 Criteria for the Design of Weirs and Barrages 663 1310 Design of Impervious Floor for Subsurface Flow 668 1311 Bligh’s Creep Theory 668 1312 Lane’s Weighted Creep Theory 671 1313 Theory of Seepage Flow 672 1314 Khosla’s Theory 675 1315 Design of Vertical Drop Weir 690 1316 Design of Glacis Weir 697 1317 Undersluices or Scouring Sluices 698 1318 Divide Wall or Divide Groyne 700 1319 Fish Ladder 700 1320 Canal Head Regulator 703 1321 Silt Control Devices 706 1322 River Training Works 709 Solved Illustrative Examples 709 Review Questions 738