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Acknowledgments, xv Preface, xvii About the companion website, xix 1 Natural resources engineering opportunities, 1
1.1 Definitions, 2
1.2 The hydrologic cycle and the water-soil-air-biotic continuum, 3
1.3 Changing land uses due to societal forces, 4
1.4 Natural resources and ecological engineering scope addressed in this text, 5
1.5 Outlook, 11 References, 14
Part One: Quantifying the Hydrologic Cycle 2 Precipitation, 19
2.1 Precipitation mechanisms, types, and measurement, 19
2.2 Precipitation analysis, 23
2.3 Introduction to hydrologic frequency analysis, 25
2.4 Local-scale precipitation analysis, 29
2.5 Calculating storm magnitudes for design purposes, 30
2.5.1 Storm simulation, 30
2.5.2 Probable maximum precipitation, 34
2.6 Pollution transport by precipitation, 34
2.7 The water quality storm, 35
2.8 Climate change and precipitation, 35
2.9 Outlook, 36 References, 37 3 Infiltration, 39
3.1 Infiltration, percolation, and subsurface flow defined, 39
3.2 Factors affecting infiltration of aqueous materials, 40
3.3 Darcy''s law, 41
3.4 Water infiltration and percolation prediction, 45
3.5 Infiltration measurement, 50
3.6 Pollutant transport by subsurface flow, 51
3.7 Outlook, 53 References, 55 4 Evapotranspiration, 57
4.1 Background and factors affecting evapotranspiration, 57
4.2 Evaporation prediction approaches, 58
4.3 Evaporation from water surfaces based solely on aerodynamic effects or mass balance, 58
4.4 Evaporation prediction from the energy-balance-Bowen-ratio method, 60
4.5 Reference evaporation prediction accounting for aerodynamic effects and energy balance - the Penman-Monteith combination equation method, 62
4.6 Empirical and approximate methods for Ep, 70
4.7 Physical simulation and measurements of ET, 74
4.8 Outlook, 77 References, 79 5 Runoff, 81
5.1 Background, 81
5.2 Watershed or catchment delineation, 84
5.3 Runoff volume for a compact watershed, 86
5.4 Peak runoff rate with compact watersheds, 93
5.5 Selecting the design storm, 103
5.6 Frequency analysis of runoff, 111
5.7 Runoff from complex watersheds, 112
5.8 Outlook, 114 References, 118
Part Two: Field- and Farm-Scale Water Quality 6 Water erosion, 123
6.1 Background, 124
6.2 Factors affecting water erosion, 124
6.3 Soil erosion versus sediment yield, 125
6.4 Soil loss tolerance, 126
6.5 Water erosion types, 126
6.6 Erosion mechanics, 128
6.7 Predicting soil detachment and upland erosion, 129
6.8 The weighted RrfCprac factor for average annual erosion computation, 138
6.9 Prediction of sediment yield, 142
6.10 Legal aspects, 145
6.11 Modeling approaches for sediment yield prediction, 145
6.12 Erosion control practices in agriculture, 148
6.13 Erosion and sediment control with construction, 149
6.14 Erosion and nutrient pollution, 152
6.15 Outlook, 152 References, 156 7 Water quality and management at farm/field scales, 159
7.1 Water quality background, 159
7.2 Important concepts and selected pollution measurement techniques, 163
7.3 Scale effects, 165
7.4 Best management practices for nonpoint pollution abatement, 169
7.5 Quantitative removal and renovation of selected pollution constituents, 176
7.6 Modeling pollution fate and transport, 178
7.7 Outlook, 179 References, 181
Part Three: Water management on the field and farm scales 8 Open channel hydraulics - fundamentals, 185
8.1 Hydraulics fundamentals, 185
8.2 Channel design and construction, 194
8.3 Outlook, 208 References, 212 9 Vegetated waterways and bioswales, 215
9.1 Vegetated waterways and diversions, 215
9.2 Bioswales, 222
9.3 Outlook, 225 References, 226 10 On-site erosion management, 229
10.1 Terraces on the farm, 230
10.2 Erosion and sediment control in urban areas, 244
10.3 Outlook, 247 References, 251 11 Hydraulics of water management structures, 253
11.1 Structure types, 254
11.2 Hydraulic concepts, 258
11.3 Stage-discharge relationships of weir inlets and flumes, 259
11.4 Discharge relations of orifices and sluice gate inlet devices, 265
11.5 Flow hydraulics of closed conduits, 265
11.6 Stage-discharge curves for culverts and spillways, 275
11.7 Closed conduit systems for urban storm water collection, 281
11.8 Water measurement structures for irrigation and aquaculture, 282
11.9 Ecologic suitability, 282
11.10 Outlook, 284 References, 287 12 Hydraulics of Impoundments, 289
12.1 Soils fundamentals for embankment construction, 290
12.2 Flood routing through reservoirs and related structures, 297
12.3 General pond design, 303
12.4 Applications, 314
12.5 Outlook, 323 References, 329 13 Shallow Groundwater Management, 331
13.1 Surface drainage, 332
13.2 Subsurface flow fundamentals, 333
13.3 Pipe drainage, 335
13.4 Shallow wells, 347
13.5 Uniform infiltration and drainage to a nearby stream, 353
13.6 Outlook, 354 References, 356 14 Introduction to irrigation, 359
14.1 Irrigation systems overview, 360
14.2 Soil-water-plant relations, 362
14.3 Soil intake rate, 369
14.4 Water quality issues and leaching requirement for crop well-being, 369
14.5 Irrigation efficiency, 372
14.6 Effective rainfall and irrigation scheduling, 374
14.7 Computing ET requirements - peak ET, 376
14.8 Computing ET requirements - seasonal water use, 376
14.9 Irrigation pumping rate for meeting ET requirements, 377
14.10 Water rights and legal underpinnings, 378
14.11 Manual or wheel-move lateral sprinkler system design, 378
14.12 Center pivot system specification, 390
14.13 Linear move irrigation machines, 394
14.14 Design for nontraditional applications, 394
14.15 Microirrigation system design with pressure compensated emitters, 397
14.16 Safety, 401
14.17 Outlook, 401 References, 405
Part Four: Basin-scale Processes 15 Ecological assessment and engineering, 409
15.1 Watershed assessment background, 410
15.2 Watershed assessment methods, 411
15.3 Principles of ecological engineering and ecosystem services, 445
15.4 Outlook, 447 References, 450 Appendices A Ethics, stakeholder views, case studies, and precision, 457 A catalog of ethical views, 458 Making sense of the ethical catalogue - one person''s view, 461 Resource economics - "social traps", 462 Case study one - pitcher plant community viability, 463 Case study 2 - a hypothetical case concerning clean water act compliance, 466 Significant digits and presentation precision, 467 References, 468 B Selected Excel® and other software package solutions, 471 Selected symbolic solutions, 472 Determining bottom width and depth in a trapezoidal channel with known slope, side slope, and permissible velocity, 472 Determining depth and side slope in a triangular channel with known slope and permissible velocity, 473 Determining slope and depth in a triangular channel with known flow rate, permissible velocity and side slope (z), 473 References, 474 C Tractive force method for waterway design, 475 Riprap-lined or earthen waterways, 475 Vegetated waterways, 477 References, 479 D Land forming, structure selection, installation, and forces on conduits, 481 Land forming computations, 481 Impoundment and embankment volume calculations, 483 Setting slope stakes for cuts and fills, 486 Techniques for installation of channels and other structures, 486 Layout of circular curves, 487 Small channels or minor topography modifications, 489 Terrace construction and layout, 491 Post-construction stormwater management options, 494 Dry detention pond, 494 Extended wet detention pond, 494 Constructed wetlands, 494 Grass swale, 494 Filter strip and level spreader, 495 Infiltration trench, 495 Oil/grit separator, 495 Source (EPA post-construction) key definitions, 495 Materials specifications for channels and structures, 498 Rural road construction, 498 Buried pipe loading, 499 Trench safety, 502 References, 503 E Selected units conversions, 505 Index, 507