PREFACE xiii
ACKNOWLEDGMENTS xvii
1 INTRODUCTION: COMPREHENSIVE WATERSHED ASSESSMENT AND MANAGEMENT 1
1.0 Introduction 1
1.1 Sustainability 3
1.2 Watershed Assessment and Management 4
1.3 Comprehensive Watershed Management Concepts 4
1.4 Political versus Natural Resource Management 10
1.5 Summary 13
PART A: WATERSHED PROCESSES 17
2 PHYSIOGRAPHY 19
2.0 Introduction 19
2.1 Physiography and Physiographic Provinces 19
2.2 Geology 19
2.3 Soils 30
2.4 Topography 45
2.5 Summary 47
3 CLIMATE, PRECIPITATION, HYDROLOGIC CYCLE 49
3.0 Introduction 49
3.1 Climate Classification 49
3.2 Precipitation 49
3.3 Hydrologic Cycle, Water Balance, and Water Budget 56
3.4 Anthropogenic (Man-made) Changes to the Water Balance 64
3.5 Low Flow 71
3.6 Summary 73
4 HYDROGEOLOGY 76
4.0 Introduction 76
4.1 Groundwater 76
4.2 Flow through Porous Media 82
4.3 Fluid Movement in Unsaturated Media 82
4.4 Fluid Movement in Saturated Media 83
4.5 Flow Through Secondary Openings in Dense Materials 84
4.6 Nitrogen Pollution 84
4.7 Summary 90
5 HYDROGEOMORPHOLOGY (WATERSHED AND STREAM MORPHOLOGY) 92
5.0 Introduction 92
5.1 Hydrogeomorphology 93
5.2 Watershed Classifications 97
5.3 Stream Classifications 104
5.4 Watershed Hydrology 111
5.5 Summary 113
6 LAKES, RESERVOIRS, STREAMS, AND WETLANDS 115
6.0 Introductio 115
6.1 Lentic Water (Ponds, Lakes, Reservoirs) 116
6.2 The Great Dam Debate 123
6.3 Lotic Water (Streams and Rivers) 124
6.4 Physical Properties of Receiving Waters 125
6.5 Wetlands 125
6.6 Summary 133
7 ECOLOGY/HABITAT 135
7.0 Introduction 135
7.1 Ecosystems 135
7.2 Biodiversity 138
7.3 Stressors 139
7.4 Bioindicators 140
7.5 Fisheries 147
7.6 Threatened and Endangered Species 149
7.7 Summary 152
8 WATER QUALITY: NONPOINT SOURCE POLLUTION 155
8.0 Introduction 155
8.1 Water Quality 155
8.2 Chemical Properties of Precipitation 156
8.3 Chemical Properties of Receiving Waters 161
8.4 Point versus Nonpoint Source Pollution 163
8.5 Nonpoint Source (NPS) Pollutants 165
8.6 Buildup and Washoff in Urban Areas 170
8.7 Runoff Pollutant Sources 173
8.8 Summary 173
PART B: WATERSHED ASSESSMENT 183
9 WATERSHED ASSESSMENT: DATA COLLECTION 185
9.0 Introduction 185
9.1 Project Initiation 186
9.2 Establish the Watershed Assessment Team 186
9.3 Involve Citizenry 187
9.4 Select a Consultant 188
9.5 Implement Quality Assurance/Quality Control (QA/QC) 188
9.6 Identify General Problems in the Watershed 188
9.7 Develop Goals and Objectives 189
9.8 Obtain Grant(s) 193
9.9 Hold Public Meetings and Conduct Surveys 194
9.10 Collect Data 196
9.11 Check Local Ordinances 213
9.12 Assimilate Data 214
9.13 Proceed with Analysis: Assessment and Modeling 214
9.14 Write the Plan Report 214
9.15 Summary 216
10 GEOGRAPHIC INFORMATION SYSTEMS 217
10.0 Introduction 217
10.1 Use of GIS for Watershed Assessment 217
10.2 Units, Scale, and Accuracy 218
10.3 Coordinate Systems, Datums, and Projections 219
10.4 GIS Data Types 222
10.5 Metadata 225
10.6 GIS Layers and Data Sources Useful for Watershed Assessment and Analysis 226
10.7 Summary 272
11 PRECIPITATION AND STREAM FLOW DATA 277
11.0 Introduction 277
11.1 Precipitation Measurements 277
11.2 Stream Flow Measurements 288
11.3 Base Flow Separation 307
11.4 Summary 312
12 WATERSHED HYDROLOGY AND MODELING 315
12.0 Introduction 315
12.1 Drainage Area 316
12.2 Time-of-Concentration and Watershed Lag 316
12.3 Runoff 320
12.4 Routing 325
12.5 Modeling Process 327
12.6 Sensitivity Analysis 328
12.7 GIS 331
12.8 Model Calibration Process 331
12.9 Verification 355
12.10 Calibrated Model Runs 357
12.11 Summary 357
13 STREAM AND RIVER MORPHOLOGIC ASSESSMENT 361
13.0 Introduction 361
13.1 Age Classifications 362
13.2 Stream Form (Pattern) 362
13.3 Stream Factors 364
13.4 Stream Classifications 374
13.5 Performing a Fluvial Geomorphological Assessment 379
13.6 Summary 383
14 ECOLOGY: HABITAT CLASSIFICATION AND ASSESSMENT 385
14.0 Introduction 385
14.1 Longitudinal Changes in Stream Ecosystems 385
14.2 Ecosystem Classifications 386
14.3 Ecoregions and Watershed Management 393
14.4 Rapid Bioassessment Protocol (RBP) 394
14.5 Species Diversity Inventory 395
14.6 Aquatic Habitat 395
14.7 Conducting an Aquatic Survey 396
14.8 Aquatic Organism Assessment 400
14.9 Summary 400
15 NONPOINT SOURCE POLLUTION LOAD ASSESSMENT 403
15.0 Introduction 403
15.1 Existing Pollutant Loading Data (NURP) 403
15.2 Field Data Collection and Monitoring 405
15.3 Total Maximum Daily Load (TMDL) 411
15.4 Pollutant Loading Equations and Methods 413
15.5 Revised Universal Soil Loss Equation (RUSLE) 419
15.6 Computer Simulation Models 428
15.7 Summary 430
PART C: WATERSHED MANAGEMENT 433
16 AGENCY ROLES, PROGRAMS, REGULATIONS, AND POLICIES 435
16.0 Introduction 435
16.1 Water Quality Criteria and Standards 436
16.2 Regulations 438
16.3 State, Regional, and Local Regulations 457
16.4 Federal Programs 460
16.5 Greenways and Rivers Conservation Plans 468
16.6 Land Trusts 468
16.7 Summary 469
17 SYSTEMATIC APPROACH TO WATERSHED ASSESSMENT: THE DIGITAL WATERSHED, WATERSHED ANALYSIS, GIS, AND MODELING 471
17.0 Introduction 471
17.1 GIS Applications 471
17.2 Compiling the Digital Watershed 472
17.3 Data Analysis 473
17.4 The GIS Overlaying Procedure 486
17.5 GIS in Hydrologic and Hydraulic Analyses 486
17.6 GIS and Floodplain Management 493
17.7 GIS and Groundwater Management 494
17.8 GIS and Water Quality 495
17.9 Management District Determination 495
17.10 Displaying the Results 497
17.11 Summary 497
18 STORMWATER MANAGEMENT ON A WATERSHED BASIS: REGIONAL STORMWATER MANAGEMENT 499
18.0 Introduction 499
18.1 Urbanization/Land Development 501
18.2 Stormwater Management and Land Development 501
18.3 Watershed-Level Stormwater Runoff Control Management Philosophy 505
18.4 Conventional On-Site Runoff Control versus Watershed Level Runoff Control 505
18.5 Release Rate Percentage Concept 507
18.6 Minimum Reasonable Release Rate Determination 513
18.7 Variable Stormwater Management Districts 514
18.8 Summary 523
19 ON-SITE STORMWATER MANAGEMENT AND CONSERVATION DESIGN 526
19.0 Introduction 526
19.1 Traditional Procedure for Site Design Stormwater Management 527
19.2 Best Management Practices 529
19.3 Five-Phase Approach to Stormwater Management 530
19.4 Nonstructural BMPs and Stormwater Management 550
19.5 The Role of Soils in Low Impact Development 564
19.6 Recommended Procedure for Site Design Stormwater Management: The Low Impact Development Design Planning Process 565
19.7 Advantages and Benefits of LID Design 569
19.8 Future Implementation 569
19.9 Structural BMPs 570
19.10 Summary 583
20 FLOODPLAIN MANAGEMENT AND RIPARIAN BUFFERS 587
20.0 Introduction 587
20.1 Federal Emergency Management Agency¢s Flood Insurance Program 589
20.2 Land Development Process in the Floodplain 594
20.3 Room for Improvement 599
20.4 Floodplain and Riparian Buffer Management 602
20.5 Riparian Buffers and Stream Orders 604
20.6 Riparian Buffer Assessment 605
20.7 Riparian Buffer Management 606
20.8 Summary 610
21 STREAM AND LAKE MANAGEMENT 613
21.0 Introduction 613
21.1 Streambank Management Using FGM Techniques 613
21.2 Lake Management 614
21.3 Summary 620
22 GROUNDWATER AND INTEGRATED WATER RESOURCES MANAGEMENT 623
22.0 Introduction 623
22.1 Water Supply Plan 623
22.2 Wellhead Protection Study 625
22.3 Integrated Water Resources Management 632
22.4 Summary 646
23 SUMMARY 648
APPENDIX A SELECTED LIST OF GIS DATA AND RELATED SITES 651
APPENDIX B ACRONYMS 652
GLOSSARY 657
INDEX 690
