Water distribution systems handbook

Front Matter......Page 1
Contributors......Page 3
Preface......Page 4
Acknowledgments......Page 6
About the Editor......Page 7
18. Reliability Analysis for Design......Page 0
Table of Contents......Page 8
1.1 Background......Page 36
1.2.1 Ancient Urban Water Supplies......Page 38
1.2.2 Status of Water Distribution Systems in the 19th Century......Page 44
1.2.3 Perspectives on Water Distribution Mains in the United States......Page 45
1.3.1 The Overall Systems......Page 51
1.3.2 System Components......Page 55
1.3.3 System Operation......Page 61
1.3.4 The Future......Page 64
References......Page 65
2.1 Introduction......Page 66
2.2 Importance of Pipeline Systems......Page 67
2.3 Numerical Models: Basis for Pipeline Analysis......Page 68
2.4 Modeling Approach......Page 69
2.4.1 Properties of Matter (What?)......Page 70
2.4.2 Laws of Conservation (How?)......Page 71
2.4.3.1 Law of Conservation of Chemical Species......Page 72
2.4.3.2 Steady Flow......Page 73
2.4.4 Newton\'s Second Law......Page 74
2.5 System Capacity: Problems in Time and Space......Page 75
2.6 Steady Flow......Page 78
2.6.1 Turbulent Flow......Page 80
2.6.2 Headloss Caused by Friction......Page 81
2.6.3 Comparison of Loss Relations......Page 83
2.6.4 Local Losses......Page 86
2.6.5 Tractive Force......Page 87
2.6.6 Conveyance System Calculations: Steady Uniform Flow......Page 88
2.6.7 Pumps: Adding Energy to the Flow......Page 91
2.6.8 Sample Application Including Pumps......Page 93
2.6.9 Networks - Linking Demand and Supply......Page 95
2.7 Quasi-Steady Flow: System Operation......Page 96
2.8.1 Importance of Waterhammer......Page 98
2.8.2 Cause of Transients......Page 100
2.8.3.2 Implication 2. Water is Only Slightly Compressible......Page 101
2.8.3.3 Implication 3. Local Action and Control of Valves......Page 102
2.8.4 Equation of State-Wavespeed Relations......Page 103
2.8.5 Increment of Head-Change Relation......Page 104
2.8.6 Transient Conditions in Valves......Page 105
2.8.6.1 Gate Discharge Equation......Page 106
2.8.6.2 Alternate Valve Representation......Page 107
References......Page 108
3.1.1 Overview......Page 110
3.2.1 Water Demands......Page 111
3.2.2.2 Storage......Page 116
3.2.2.5 Service Pressures......Page 117
3.2.4 Computer Models and System Modeling......Page 118
3.2.4.2 Software Packages......Page 119
3.3.1 Alignment......Page 120
3.3.3 Rights-of-Way......Page 122
3.4 Piping Materials......Page 123
3.4.1.5 Fittings......Page 124
3.4.1.6 Linings......Page 126
3.4.1.7 Coatings......Page 127
3.4.2.1 Materials......Page 128
3.4.2.3 Joints......Page 129
3.4.2.6 Linings and Coatings......Page 130
3.4.3.2 Available Sizes and Thicknesses......Page 131
3.4.3.5 Fittings......Page 132
3.4.3.6 Linings and Coatings......Page 133
3.4.4 Reinforced Concrete Pressure Pipe (RCPP)......Page 135
3.4.4.2 Prestressed Steel Cylinder Pipe, AWWA C301......Page 136
3.4.4.4 Pretensioned Steel Cylinder, AWWA C300......Page 138
3.4.5.1 Materials......Page 139
3.4.5.3 Joints......Page 140
3.4.6.1 Available Sizes and Thicknesses......Page 141
3.4.7 Pipe Material Selection......Page 142
3.5.2 Loads on Buried Pipe......Page 144
3.5.2.1 Earth Loads......Page 145
3.5.2.2 Rigid Pipe......Page 146
3.5.2.3 Flexible Pipe......Page 147
3.5.3 Thrust Restraint......Page 148
3.5.3.1 Thrust Blocks......Page 149
3.5.3.2 Restrained Joints......Page 151
3.6.1 Isolation Valves......Page 154
3.6.1.2 Butterfly Valves......Page 155
3.6.2.1 Pressure-Reducing Valve......Page 156
3.6.3 Blow-offs......Page 157
References......Page 158
4.1.1 Configuration and Components of Water Distribution Systems......Page 160
4.1.3 Network Components......Page 162
4.2.1 Series and Parallel Pipe Systems......Page 164
4.2.2 Branching Pipe Systems......Page 166
4.2.3.1 Hardy Cross Method......Page 170
4.2.3.2 Linear Theory Method......Page 176
4.2.3.3 Newton-Raphson Method and the Node Equations......Page 177
4.2.3.4 Gradient Algorithm......Page 179
4.2.3.5 Comparison of Solution Methods......Page 181
4.2.3.6 Extended-Period Simulation......Page 182
4.3.1 Governing Equations......Page 183
4.3.2.1 Loop Formulation......Page 184
4.4 Computer Modeling of Water Distribution Systems......Page 185
4.4.2 Model Calibration......Page 186
References......Page 187
5.1.1 Pump Standards......Page 189
5.1.2 Pump Definitions and Terminology......Page 190
5.1.3 Types of Centrifugal Pumps......Page 194
5.2.2.1 Hazen-Williams Equation......Page 196
5.2.2.3 Darcy-Weisbach Equation......Page 199
5.2.3 Hydraulics of Valves......Page 200
5.2.6 Variable-Speed Pumps......Page 201
5.3.1 Introduction: Discharge-Specific Speed......Page 206
5.4.1 Net Positive Suction Head Available......Page 207
5.4.2 Net Positive Suction Head Required by a Pump......Page 208
5.5 Corrected Pump Curves......Page 210
5.6.1 Row Range of Centrifugal Pumps......Page 215
5.6.3 Summary of Pump Selection......Page 216
5.7.1.1 Pump Operating Ranges......Page 218
5.7.2 Piping......Page 220
5.7.2.3 Design of Pipe Wall Thickness (Pressure Design)......Page 221
5.7.2.4 Design of Pipe Wall Thickness (Vacuum Conditions)......Page 222
5.8.1 Effect of Surge on Valve Selection......Page 223
References......Page 224
Appendix......Page 225
6.1 Introduction to Waterhammer and Surging......Page 229
6.2.2 Acoustic Velocity......Page 230
6.2.3 Joukowsky (Waterhammer) Equation......Page 231
6.3 Hydraulic Characteristics of Valves......Page 232
6.3.1 Descriptions of Various Types of Valves......Page 233
6.3.3 Definition of Hydraulic Performance of Valves......Page 234
6.3.4 Typical Geometric and Hydraulic Valve Characteristics......Page 236
6.4 Hydraulic Characteristics of Pumps......Page 237
6.4.2 Homologous (Affinity) Laws......Page 238
6.4.3 Abnormal Pump (Four-Quadrant) Characteristics......Page 240
6.4.4 Representation of Pump Data for Numerical Analysis......Page 243
6.4.5 Critical Data Required for Hydraulic Analysis of Systems with Pumps......Page 244
6.5.1 Critical Parameters for Transients......Page 246
6.5.2 Critique of Surge Protection......Page 248
6.5.3 Surge Protection Control and Devices......Page 250
6.6 Design Considerations......Page 252
6.7 Negative Pressures and Water Column Separation in Networks......Page 254
6.9.1 Case Study with One-Way and Simple Surge Tanks......Page 255
6.9.2 Case Study with Air Chamber......Page 256
6.9.3 Case Study with Air-Vacuum Breaker......Page 259
References......Page 260
7.2 Problem Definition......Page 262
7.3 Mathematical Formulation......Page 264
7.4.1 Branched Systems......Page 265
7.4.2 Looped Pipe Systems via Linearization......Page 266
7.4.3 General System Design via Nonlinear Programming......Page 268
7.4.4 Stochastic Search Techniques......Page 269
7.5 Applications......Page 270
7.6 Summary......Page 273
References......Page 274
8.2 Disinfection of New Water Mains......Page 277
8.2.3.1 The Tablet Method......Page 278
8.2.6 Disposal of Highly Chlorinated Water......Page 279
8.3.1.2 Method 2......Page 280
8.4.2 Cross-Connection Control Programs......Page 281
8.4.3.3 Atmospheric and Pressure Vacuum Breakers, and Barometric Loops......Page 282
8.4.4 Application of Backflow Preventers......Page 283
8.5.2 Flushing Procedures......Page 284
8.5.4 Alternating of Disinfectants......Page 285
References......Page 286
9.1.1 Overview......Page 288
9.1.2 Definitions......Page 289
9.2.1 Loss of Disinfectant Residual......Page 290
9.2.1.1 Disinfection Methods......Page 291
9.2.1.3 Mitigation of Disinfectant Loss......Page 292
9.2.3 Internal Corrosion......Page 293
9.2.3.2 Factors Affecting Corrosion......Page 294
9.2.3.4 Control of Corrosion......Page 295
9.2.4.2 Composition......Page 296
9.2.4.4 Treatment and Control......Page 297
9.3.2 Synoptic Monitoring......Page 298
9.4 Water-Quality Modeling......Page 302
9.4.2 Governing Equations......Page 303
9.4.2.4 Bulk Flow Reactions......Page 304
9.4.3.1 Steady-State Models......Page 305
9.4.3.2 Dynamic Models......Page 306
9.4.4.3 Reaction-Rate Data......Page 307
9.4.5.3 Uses for Hydraulic Calibration......Page 308
References......Page 309
10.2 Basic Concepts......Page 312
10.2.4 Emergency Storage......Page 313
10.2.7 Hydraulic Transient Control......Page 314
10.3.1 Floating Versus Pumped Storage......Page 315
10.3.2 Ground Versus Elevated Tank......Page 316
10.3.5 Pressurized Tanks......Page 317
10.4.1 Clearwell Storage......Page 318
10.4.3 Multiple Tanks in the Pressure Zone......Page 319
10.5.1 Setting Tank Overflow Levels......Page 320
10.5.3 Identifying Pressure Zones......Page 321
10.6.1 Trade-offs in Tank Volume Design......Page 322
10.6.3.1 Equalization Storage......Page 323
10.6.3.2 Fire Storage......Page 325
10.6.4 Staging Requirements......Page 327
10.6.5 Useful Dead Storage......Page 328
10.7.3 Overflows and Vents......Page 329
References......Page 330
11.1.1 Overview......Page 332
11.2.1.1 Loss of Disinfectant Residual......Page 333
11.2.1.3 Development of Taste and Odor......Page 334
11.2.1.6 Buildup of Iron and Manganese......Page 335
11.2.2.1 Bacterial Regrowth......Page 336
11.2.2.3 Worms and Insects......Page 337
11.2.3.2 Entry of Contaminants......Page 338
11.3.1 Ideal Flow Regimes......Page 339
11.3.3 Mixing Times......Page 340
11.3.4 Stratification......Page 341
11.3.5 Aging......Page 342
11.4.1 Routine Monitoring......Page 343
11.4.1.3 Parameters of Sediment Monitoring......Page 344
11.4.2 Sampling Methods and Equipment......Page 348
11.4.3 Monitoring Frequency and Location of Samples......Page 349
11.4.4.2 Temperature Monitoring......Page 351
11.5.1.1 Principles of Similitude......Page 354
11.5.1.2 Construction of a Model......Page 355
11.5.1.3 Types of Tracers......Page 356
11.5.2 Computational Fluid Dynamics......Page 357
11.5.2.1 Mathematical Formulations of CFD Models......Page 358
11.5.2.2 Application of CFD Models......Page 359
11.5.3.4 Application of Systems Models......Page 360
11.6.3 Flow Regimes: Complete Mix Versus Plug Flow......Page 362
11.6.3.2 Mixed Flow......Page 363
11.6.3.3 Plug Flow......Page 364
11.6.4 Stratification in Reservoirs......Page 365
11.7.1 Inspections......Page 366
11.7.2 Maintenance......Page 367
References......Page 368
12.1.1 Need for Computer Models......Page 371
12.1.3 History of Computer Models......Page 372
12.2.1.1 Network Components......Page 373
12.2.2 Compilation of Data......Page 374
12.2.2.3 Pipe Diameters......Page 375
12.2.3 Estimation of Demand......Page 376
12.2.5 Reaction-Rate Information......Page 377
12.3 Computer Model Internals......Page 378
12.3.3 Hydraulic Solution Algorithms......Page 379
12.3.5 Extended-Period Solver......Page 381
12.3.7 Output Processing......Page 382
12.4.1 Background......Page 383
12.4.2 Program Features......Page 384
12.4.3 User Interface......Page 385
12.4.4 Solver Module......Page 387
12.5 Conclusion......Page 390
References......Page 391
13.1 Introduction......Page 394
13.2 Design of Distribution Systems in the United States......Page 395
13.3 Water Quality in Networks......Page 396
13.4 Hydraulic and Water-Quality Models......Page 397
13.4.2 Dynamic Water-Quality Models......Page 398
13.5.1 North Penn Study......Page 399
13.5.1.1 Network Modeling......Page 400
13.5.1.3 Development of Dynamic Water-Quality Algoritm......Page 401
13.5.2 South Central Connecticut Regional Water Authority......Page 402
13.5.2.3 Results from the Field Study......Page 406
13.5.2.6 Analysis of Sampling Results......Page 410
13.5.2.7 Modeling of Chlorine Residual......Page 414
13.5.3 Case Study of Cabool, Missouri......Page 415
13.6 Evolution of Water Quality Modeling......Page 416
13.7 Modeling Propagation of Contaminants......Page 417
13.7.1 Case Study of the North Marin Water District......Page 418
13.7.1.1 Water-Quality Study......Page 423
13.7.1.2 Modeling of Total Trihalomethane Formations......Page 424
13.7.2 Complement to the North Marin study......Page 428
13.7.3 Waterborne Outbreak in Gideon, Missouri......Page 430
13.7.3.1 Description of the System......Page 432
13.7.3.2 Identification of the Outbreak......Page 433
13.7.3.3 Possible Causes......Page 434
13.7.3.5 Performance of the System......Page 435
13.7.3.6 Propagation of the Contaminant......Page 437
13.8.2 Case Study in Southington, Connecticut......Page 438
13.9 Summary and Conclusions......Page 439
References......Page 440
14.1.2 Network Data Requirements......Page 444
14.3 Determine Estimates of the Model Parameters......Page 446
14.3.1.1 Chart the Pipe Roughness......Page 447
14.3.1.2 Field Test the Pipe Roughness......Page 449
14.3.2 Distribution of Nodal Demands......Page 452
14.3.2.1 Spatial Distribution of Demands......Page 453
14.4.1 Fire-Flow Tests......Page 455
14.4.2 Telemetric Data......Page 456
14.5 Evaluate the Results of the Model......Page 457
14.6 Perform a Macro-Level Calibration of the Model......Page 458
14.8 Perform a Macro-Level Calibration of the Model......Page 459
14.8.3 Optimization Approaches......Page 460
References......Page 464
15.1 Introduction......Page 467
15.2.1 Typical Operating Indexes......Page 468
15.2.2 Operating Criteria......Page 469
15.2.4 Emergency Operations......Page 470
15.3 Monitoring of System Performance with SCADA Systems......Page 471
15.3.1 Anatomy of a SCADA System......Page 472
15.4 Control of Water Distribution System......Page 475
15.4.1.3 Advanced Control......Page 476
15.5 Linking of SCADA Systems with Analysis and Control Models......Page 477
15.5.1 Data Requirements of Analysis and Control Models......Page 478
15.5.2 Establishment of the Link......Page 479
15.6 Use of Central Databases in System Control......Page 481
References......Page 482
16.1 Introduction......Page 483
16.2.2 Management Strategies......Page 485
16.2.3.1 Hydraulic Network Models......Page 487
16.2.3.2 Demand Forecast Models......Page 489
16.2.3.3 Control Models......Page 490
16.2.4.1 Problem Formulation......Page 491
16.2.4.2 System Classification......Page 492
16.2.5 Summary and Conclusions......Page 496
16.3 Formulations to Satisfy Water Quality......Page 498
16.4.1 Mathematical Programming Approach......Page 502
16.4.2 Simulated Annealing Approach......Page 505
16.4.3 Development of Cost Function......Page 507
16.4.4 Sample Application......Page 509
16.5 Optimal Scheduling of Booster Disinfection......Page 511
16.5.1 Background 1: Linear Superposition......Page 516
16.5.2 Background 2: Dynamic Network Water-Quality Models in a Planning Context......Page 517
16.5.4 Optimal Location and Scheduling of Booster-Station Dosage as a Mixed-Integer Linear Programming Problem......Page 519
16.5.5 Optimal Location of Booster Stations as a Maximum Set-Covering Problem......Page 521
16.5.6 Solution of the Optimization Models......Page 523
16.5.7 Available Software......Page 524
16.5.8 Summary......Page 525
References......Page 526
17.1.1.1 Normal Wear......Page 531
17.2 Unaccounted-for Water......Page 532
17.2.2 Understanding the Causes of Unaccounted-for Water......Page 533
17.2.3.1 Water Main Leakage......Page 535
17.2.3.4 Fire Fighting......Page 537
17.2.3.9 Meter under Registration......Page 538
17.2.4 Summary......Page 539
17.3.1.1 External Soil Corrosion......Page 540
17.3.2 External Loads......Page 541
17.3.4 Pressure-Related Breaks......Page 543
17.3.5 Repair Versus Replacement......Page 544
17.4.1.2 Hydraulic Modeling......Page 546
17.4.2.1 Closed Isolating Valves......Page 547
17.4.2.3 Carrying Capacity......Page 548
17.4.2.4 Inadequate Capacity......Page 549
17.4.3 Pipe Rehabilitation Technology......Page 550
17.5 Maintenance Information Systems......Page 551
17.5.3 Geographic Information Systems......Page 552
17.5.5 SCADA Systems......Page 553
References......Page 554
18.1.1 Need and Justification......Page 559
18.1.2 Definitions of Distribution System Repairs......Page 561
18.1.3.1 Performance Failure......Page 562
18.1.4 Reliability: Indexes and Approaches......Page 563
18.2.1.1 Piping Materials......Page 564
18.2.1.4 Looped Water Distribution System......Page 565
18.2.1.8 Emergency Controls......Page 566
18.2.1.12 Operational Considerations......Page 567
18.2.2.2 Diagrams of Distribution Segments......Page 568
18.2.2.4 Emergency Interconnections......Page 569
18.2.2.6 Typical Cross-Intersections......Page 571
18.2.2.7 Application of Segments in Valve Locations and Reliability Evaluation......Page 572
18.3.1 Failure Density, Failure Rate, and Mean Time to Failure......Page 573
18.3.2 Availability and Unavailability......Page 577
18.4.1 Reliability of a System Failure......Page 580
18.4.2 Failure Modes......Page 581
18.4.3 Approaches to the Assessment of Reliability......Page 584
18.4.4.1 Simulation Models......Page 587
18.4.4.2 Analytical Approaches......Page 591
18.4.4.4 Redundancy Based Measures......Page 597
18.4.5 Overview of Reliability Measures......Page 598
18.4.6 Observations......Page 600
18.5 Measure of Link Importance......Page 601
References......Page 607
A......Page 611
B......Page 612
C......Page 613
D......Page 616
E......Page 617
F......Page 618
H......Page 619
L......Page 620
M......Page 621
N......Page 622
O......Page 623
P......Page 624
R......Page 630
S......Page 632
T......Page 636
U......Page 637
V......Page 638
W......Page 639