CONTENTS
Contributing Authors xi
Revision History xiii
Contacting Bentley xv
Foreword xvii
CHAPTER 1 BASIC HYDRAULIC PRINCIPLES 1
1.1 General Flow Characteristics 1
System of Units 1
Flow Rate and Velocity 1
Area, Wetted Perimeter, and Hydraulic Radius 2
Flow Conveyance 3
Steady Flow 4
Uniform Flow 4
Laminar Flow, Turbulent Flow, and Reynolds Number 5
1.2 Energy 7
The Energy Principle 7
The Energy Equation 8
Hydraulic Grade 8
Energy Grade 9
Energy Losses and Gains 9
1.3 Friction Losses 10
Manning's Equation 11
Chezy's (Kutter's) Equation 11
Hazen-Williams Equation 12
Darcy-Weisbach (Colebrook-White) Equation 12
Typical Roughness Factors 13
1.4 Pressure Flow 14
1.5 Open-Channel Flow 16
Specific Energy and Critical Flow 16
1.6 Orifices and Weirs 19
Orifices 20
Weirs 22
1.7 Computer Applications 26
1.8 FlowMaster 27
1.9 Tutorial Example 28
Tutorial 1 - Open Channels 28
Tutorial 2- Pressure Pipes 30
1.10 Problems 34
CHAPTER 2 BASIC HYDROLOGY 39
2.1 Rainfall 39
Basic Rainfall Characteristics 39
Return Period and Frequency 39
Types of Rainfall Data 40
2.2 Rainfall Abstractions and Runoff Volume 49
Watershed Area 49
Rainfall Abstractions 50
Determining Runoff Volume 51
Horton Infiltration Equation 52
Runoff Coefficient 55
NRCS (SCS) Curve Number Method 57
2.3 Computing Peak Runoff Flow Rate 64
Time of Concentration 64
The Rational Method 69
NRCS (SCS) Peak Flow Estimation 73
2.4 Computing Hydrographs 79
Creating Runoff (Effective Rainfall) Hyetographs 80
Unit Hydrographs 83
Discrete Convolution 90
2.5 Problems 95
CHAPTER 3 INLETS, GRAVITY PIPING SYSTEMS,
AND STORM SEWER DESIGN 97
3.1 Inlet Design Overview 97
3.2 Gutter Sections on Grade 98
3.3 Inlets on Grade 100
Grate Inlets on Grade 100
Curb Inlets on Grade 102
Combination Inlets on Grade 103
3.4 Inlets in Sag 104
3.5 Inlet Design Overview 107
Inlet and Gutter Problems Using FlowMaster 107
Inlet and Gutter Network Problems Using StormCAD 108
3.6 Gradually Varied Flow 108
Flow Classification 109
Energy Balance 112
3.7 Mixed Flow Profiles 113
Sealing Conditions 113
Rapidly Varied Flow 113
3.8 Storm Sewer Applications 114
Hydrology Model. 114
3.9 StormCAD 116
How Can You Use StormCAD? 116
Analysis and Design 117
Profiles 117
3.10 Tutorial Examples 117
Tutoriall-Design of a Network with Auto Design 117
3.11 Problems 128
CHAPTER 4 CULVERT HYDRAULICS 143
4.1 Culvert Systems 143
Culvert Hydraulics 144
4.2 Outlet Control Hydraulics 144
Friction Losses 146
Entrance Minor Loss 146
Exit Minor Loss 148
Gradually Varied Flow Analysis 148
4.3 Inlet Control Hydraulics 148
Unsubmerged Flow 150
Submerged Flow 150
4.4 CulvertMaster 153
How Can You Use CulvertMaster? 153
4.5 Tutorial Example 154
4.6 Problems 157
CHAPTER 5 DETENTION POND DESIGN 161
5.1 Overview of Stormwater Detention 161
5.2 Basic Design Considerations 162
Pre-Development versus Post-Development Criteria and Recurrence Frequency 162
Types and Configurations of Stormwater Detention
Facilities 163
5.3 Detention Pond Modeling Concepts 164
5.4 Components of Detention Facilities 166
Dam Embankments 166
Freeboard 166
Pond Bottoms and Side Slopes 167
Outlet Structures 167
Overflow Spillways 168
5.5 Routing Data: Storage and Hydraulic Relationships 168
Stage versus Storage Volume 168
Stage versus Discharge 173
Composite Stage versus Discharge Relationships 177
5.6 Storage Indication Method 181
5.7 Stormwater Detention Analysis Procedure 185
5.8 PondPack 191
What Is PondPack? 191
How Can You Use PondPack for Windows? 191
5.9 Tutorial Example 192
Tutoriai2-Design a Detention Pond for a Small
Development 198
5.10 Problems 211
CHAPTER 6 PRESSURE PIPING SYSTEMS AND
6.1 WATER QUALITY ANALYSIS 215
Pressure Systems 215
Water Demands 215
6.2 Energy Losses 219
Friction Losses 219
Minor Losses 219
6.3 Energy Gains-Pumps 222
Variable-Speed Pumps 222
Constant Horsepower Pumps 223
6.4 Control Valves 224
Check Valves (CVs) 224
Flow Control Valves (FCVs) 225
Pressure Reducing Valves (PRVs) 225
Pressure Sustaining Valves (PSVs) 225
Pressure Breaker Valves (PBVs) 225
Throttle Control Valves (TCVs) 225
6.5 Pipe Networks 225
Conservation of Mass-Flows and Demands 226
Conservation of Energy 227
6.6 Network Analysis 227
Steady-State Network Hydraulics 227
Extended- Period Simulation 228
6.7 Water Quality Analysis 228
Age 228
Trace 229
Constituents 229
Initial Conditions 230
Numerical Methods 231
Discrete Volume Method 231
Time-Driven Method 232
6.8 Automated Optimization 232
Model Calibration 233
System Design 234
6.9 WaterGEMS 234
What Does WaterGEMS Do? 234
How Can You Use WaterGEMS? 235
6.9 Tutorial Example 236
Tutorial 1 -Three Pumps in Parallel. 236
Tutorial 2- Water Quality 243
Tutorial 3- Pumping Costs 253
Tutorial 4- Pipe Sizing using Darwin Designer 254
Tutorial 5 -Model Calibration using Darwin Calibrator 259
6.10 Problems 262
CHAPTER 7 HYDRAULIC TRANSIENTS IN DISTRIBUTION SYSTEMS 279
7.1 Hydraulic Transients 279
Transient Flow 280
Common Causes 282
7.2 Hydraulic Transient Theory 282
General Modeling Equations 283
Speed and Pressure of Transients 284
7.3 Minimizing Transients in Systems 288
Design Strategies 288
Protection Devices 289
7.4 Modeling Hydraulic Transients 291
7.5 Hammer 293
What Does HAMMER Do? 293
7.6 Tutorial Example 293
7.7 Problems 302
CHAPTER 8 SANITARY SEWER DESIGN 305
8.1 Sanitary Sewer Systems 305
Common Sanitary Sewer Elements 306
8.2 Loading 307
Common Load Types 307
Sanitary Unit Loading 309
Extreme Flow Factors 311
Common Variable Peaking Factors (PF) 311
Wet-Weather Loading 313
8.3 Extended-Period Simulations 314
Overview 314
Routing Overview 315
Hydrologic and Hydraulic Time Steps 317
8.4 SewerCAD 317
What Does SewerCAD Do? 317
How Can You Use SewerCAD? 318
8.5 Tutorial Examples 319
Tutorial!- Pump Size for Peak Flows 319
Tutorial2- 24-Hour Simulation of Dry Weather Flow 329
Tutorial 3 - Constructing a Profile 336
8.6 Problems 338
CHAPTER 9 DYNAMIC MODELING 349
9.1 Introduction 349
9.2 Dynamic Modeling 350
St Venant Equations 350
Numerical Solution 352
Initial and Boundary Conditions 353
9.3 Hydrograph Routing Effects 354
9.4 Simplified Routing Models 355
Diffusion Wave 356
Kinematic Wave 357
Muskingum Routing 357
Muskingum-Cunge Method 358
9.5 Why Use an Unsteady Flow Model? 359
9.6 SewerGEMS 360
What Does SewerGEMS Do? 360
How Can You Use SewerGEMS? 361
9.7 Tutorial Examples 362
Tutorial 1 - Stormwater Conveyance System Performance 362
Tutorial 2 - Pump Stations and Force Mains in a
Sanitary Sewer System 371
9.8 Problems 378
APPENDIX A BENTLEY SYSTEMS SOFTWARE 393
A .l Software Packages 393
A.2Software Installation and Licensing 394
Installing and Activating the Software 395
Checking Out Licenses for Disconnected Use 395
Installation for the MicroStation, AutoCAD, or
ArcGIS Platform 396
Troubleshooting 396
Technical Support 397
A.3 General Tips and Common Tools 397
Online Help 397
Graphical Editor 398
Table Manager and Table Customization 399
FlexUnits 401
APPENDIX B SCENARIO MANAGEMENT 405
B.1 Overview 405
B.2 About This Appendix 406
B.3 Before Haestad Methods: Distributed Scenarios 406
B.4 With Haestad Methods: Self-Contained Scenarios 407
B.5 The Scenario Cycle 407
Scenario Anatomy: Attributes and Alternatives 407
A Familiar Parallel 408
B.6 Scenario Behavior: Inheritance 409
Overriding Inheritance 410
Dynamic Inheritance 410
When Are Values Local, and When Are They Inherited? 411
Minimizing Effort through Attribute Inheritance 411
Minimizing Effort through Scenario Inheritance 412
B.7 A Water Distribution Example 413
Building the Model (Average Day Conditions) 414
Analyzing Different Demands (Maximum Day Conditions) 414
Another Set of Demands (Peak Hour Conditions) 415
Correcting an Error 415
Analyzing Improvement Suggestions 416
Finalizing the Project 417
INDEX 419