Water and Wastewater Calculations Manual ABOUT THE AUTHOR Shun Dar Lin is an Emeritus Faculty of University of Illinois and in Taiwan A registered professional engineer in Illinois, he has published nearly 100 papers, articles, and reports related to water and wastewater engineering Dr Lin brings to the book a background in teaching, research, and practical field experience spanning nearly 50 years Dr Lin received his Ph.D in Sanitary Engineering from Syracuse University, an M.S in Sanitary Engineering from the University of Cincinnati, and a B.S in Civil Engineering from National Taiwan University He has taught and conducted research since 1960 at the Institute of Public Health of National Taiwan University In 1986, Dr Lin received the Water Quality Division Best Paper Award for “Giardia lamblia and Water Supply” from the American Water Works Association He developed the enrichmenttemperature acclimation method for recovery enhancement of stressed fecal coliform The method has been adopted in the Standard Methods for the Examination of Water and Wastewater since the 18th edition (1990) Dr Lin is a life member of the American Society of Civil Engineers, the American Water Works Association, and the Water Environment Federation He is a consultant to the governments of Taiwan and the United States and for consultant firms Note: This book was written by Dr Shun Dar Lin in his private capacity Copyright © 2007, 2001 by The McGraw-Hill Companies, Inc Click here for terms of use Water and Wastewater Calculations Manual Shun Dar Lin C C Lee Editor of Handbook of Environmental Engineering Calculations Second Edition New York Chicago San Francisco Lisbon London Madrid Mexico City Milan New Delhi San Juan Seoul Singapore Sydney Toronto Copyright © 2007, 2001 by The McGraw-Hill Companies, Inc All rights reserved Manufactured in the United States of America Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher 0-07-154266-3 The material in this eBook also appears in the print version of this title: 0-07-147624-5 All trademarks are trademarks of their respective owners Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the benefit of the trademark owner, with no intention of infringement of the trademark Where such designations appear in this book, they have been printed with initial caps McGraw-Hill eBooks are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate training programs For more information, please contact George Hoare, Special Sales, at george_hoare@mcgraw-hill.com or (212) 904-4069 TERMS OF USE This is a copyrighted work and The McGraw-Hill Companies, Inc (“McGraw-Hill”) and its licensors reserve all rights in and to the work Use of this work is subject to these terms Except as permitted under the Copyright Act of 1976 and the right to store and retrieve one copy of the work, you may not decompile, disassemble, reverse engineer, reproduce, modify, create derivative works based upon, transmit, distribute, disseminate, sell, publish or sublicense the work or any part of it without McGrawHill’s prior consent You may use the work for your own noncommercial and personal use; any other use of the work is strictly prohibited Your right to use the work may be terminated if you fail to comply with these terms THE WORK IS PROVIDED “AS IS.” McGRAW-HILL AND ITS LICENSORS MAKE NO GUARANTEES OR WARRANTIES AS TO THE ACCURACY, ADEQUACY OR COMPLETENESS OF OR RESULTS TO BE OBTAINED FROM USING THE WORK, INCLUDING ANY INFORMATION THAT CAN BE ACCESSED THROUGH THE WORK VIA HYPERLINK OR OTHERWISE, AND EXPRESSLY DISCLAIM ANY WARRANTY, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE McGraw-Hill and its licensors not warrant or guarantee that the functions contained in the work will meet your requirements or that its operation will be uninterrupted or error free Neither McGraw-Hill nor its licensors shall be liable to you or anyone else for any inaccuracy, error or omission, regardless of cause, in the work or for any damages resulting therefrom McGraw-Hill has no responsibility for the content of any information accessed through the work Under no circumstances shall McGraw-Hill and/or its licensors be liable for any indirect, incidental, special, punitive, consequential or similar damages that result from the use of or inability to use the work, even if any of them has been advised of the possibility of such damages This limitation of liability shall apply to any claim or cause whatsoever whether such claim or cause arises in contract, tort or otherwise DOI: 10.1036/0071476245 For more information about this title, click here Contents Preface ix Chapter Streams and Rivers General Point Source Dilution Discharge Measurement Time of Travel Dissolved Oxygen and Water Temperature Biochemical Oxygen Demand Analysis Streeter–Phelps Oxygen Sag Formula BOD Models and K1 Computation Determination of Reaeration Rate Constant K2 10 Sediment Oxygen Demand 11 Organic Sludge Deposits 12 Photosynthesis and Respiration 13 Natural Self-Purification in Streams 14 SOD of DO Usage 15 Apportionment of Stream Users 16 Velz Reaeration Curve (A Pragmatic Approach) 17 Stream DO Model (A Pragmatic Approach) 18 Biological Factors References Chapter Lakes and Reservoirs Lakes and Impoundment Impairments Lake Morphometry Water Quality Models Evaporation The Clean Lakes Program References 2 10 13 14 41 49 52 54 55 78 79 87 92 107 121 125 125 126 130 131 137 176 v vi Contents Chapter Groundwater Definition Hydrogeologic Parameters Steady Flows in Aquifers Anisotropic Aquifers Unsteady (Nonequilibrium) Flows Groundwater Contamination Setback Zones References Chapter Fundamental and Treatment Plant Hydraulics Definitions and Fluid Properties Water Flow in Pipes Pumps Water Flow in Open Channels Flow Measurements References Chapter Public Water Supply 179 180 184 195 197 198 211 217 224 227 228 236 265 272 291 306 307 Sources and Quantity of Water Population Estimates Water Requirements Regulations for Water Quality Water Treatment Processes Aeration and Air Stripping Solubility Equilibrium Coagulation Flocculation 10 Sedimentation 11 Filtration 12 Water Softening 13 Ion Exchange 14 Iron and Manganese Removal 15 Activated Carbon Adsorption 16 Membrane Processes 17 Residual from Water Plant 18 Disinfection 19 Water Fluoridation 20 Health Risks References 308 311 315 321 342 343 368 371 380 384 392 404 417 435 440 444 458 463 506 513 525 Chapter Wastewater Engineering 531 What Is Wastewater? Characteristics of Wastewater Sewer Systems Quantity of Wastewater 533 533 542 545 Contents Urban Stormwater Management Design of Storm Drainage Systems Precipitation and Runoff Stormwater Quality Sewer Hydraulics 10 Sewer Appurtenances 11 Pumping Stations 12 Sewer Construction 13 Wastewater Treatment Systems 14 Screening Devices 15 Comminutors 16 Grit Chamber 17 Flow Equalization 18 Sedimentation 19 Primary Sedimentation Tanks 20 Biological (Secondary) Treatment Systems 21 Activated-Sludge Process 22 Trickling Filter 23 Rotating Biological Contactor 24 Dual Biological Treatment 25 Stabilization Ponds 26 Secondary Clarifier 27 Effluent Disinfection 28 Advanced Wastewater Treatment 29 Sludge (Residuals) Treatment and Management 30 Wetlands References vii 549 551 551 556 562 562 568 572 574 581 586 586 588 592 607 617 621 696 711 726 726 735 742 752 796 861 884 Appendix A Illinois Environmental Protection Agency’s Macroinvertebrate Tolerance List 893 Appendix B Well Function for Confined Aquifers 899 Appendix C Solubility Product Constants for Solution at or near Room Temperature 905 Appendix D Freundlich Adsorption Isotherm Constants for Toxic Organic Compounds 909 Appendix E Factors for Conversion 913 Index 919 This page intentionally left blank Preface This manual presents the basic principles and concepts relating to water/wastewater engineering and provides illustrative examples of the subject covered To the extent possible, examples rely on practical field data and regulatory requirements have been integrated into the environmental design process Each of the calculations provided herein is solved step-by-step in a streamlined manner that is intended to facilitate understanding Examples (step-by-step solutions) range from calculations commonly used by operators to more complicated calculations required for research or design For calculations provided herein using the US customary units, readers who use the International System may apply the conversion factors listed in Appendix E Answers are also generally given in SI units for most of problems solved by the US customary units This book has been written for use by the following readers: students taking coursework relating to “Public Water Supply,” “Waste-Water Engineering,” or “Stream Sanitation”; practicing environmental (sanitary) engineers; regulatory officers responsible for the review and approval of engineering project proposals; operators, engineers, and managers of water and/or wastewater treatment plants; and other professionals, such as chemists and biologists, who need some knowledge of water/wastewater issues This work will benefit all operators and managers of public water supply and of wastewater treatment plants, environmental design engineers, military environmental engineers, undergraduate and graduate students, regulatory officers, local public works engineers, lake managers, and environmentalists Advances and improvements in many fields are driven by competition or the need for increased profits It may be fair to say, however, that advances and improvements in environmental engineering are driven instead by regulation The US Environmental Protection Agency (US EPA) sets up maximum contaminant levels, which research and project designs must reach as a goal The step-by-step solution examples provided in this book are guided by the integration of rules and regulations ix Copyright © 2007, 2001 by The McGraw-Hill Companies, Inc Click here for terms of use Index Land application (sludge) (Cont.): pollutant limitation-based calculation, 852–853 site evaluation and selection, 847 supplemental potassium (K) fertilizer, 853–861 Langbein and Durum equation, 46 Langmuir adsorption model, 441 Lateral area of influence (LAI, groundwater), 218–219 Lateral radius of influence (LRI, groundwater), 219–222 Lawrence and McCarty design equations, 627 Lawrence Livermore National Laboratory, 447 Lead: in biosolids, 846, 853 in drinking water, 325 in runoff, 557 in water, 323 Lead pipe, 246 Leakage (ion exchange), 425–426 Leakage in sewer, 542–543, 564 Leakage test (water supply piping), 320–321 Leaking storage tank, 521 Least-squares method, 19 Legionella, 322, 476, 492 Leucothrix, 663 Lime: in activated sludge process, 663 for phosphorus removal, 754–755, 760–766 sludge, lime, 798, 839 for sludge stabilization, 826 for softening water, 342, 368, 372–373, 389, 404–411, 426, 460–461, 521 for wastewater stabilization, 812, 826–830 Lime sludge stabilization, 826 Loading rate: annual pollutant loading rate for biosolids, 846 areal (stabilization ponds), 728–731 of nitrification, 778 sludge, 831, 837 solids, 606, 740–741, 802, 806–807, 814, 821–828, 840 street and road runoff, 559–560 surface (overflow), 388–392, 596, 753 931 Loads: on sewer lines, 572–574 for buried sewers, 572–574 for trench condition, 573–574 LOAFL (See Lowest-observed-adverseeffect level) Logistic curve method (water supply population estimates), 313–314 Long Term Enhanced Surface Water Treatment Rule, 335, 337–339 Lowest-observed-adverse-effect level (LOAFL), 332, 333 LRI (See Lateral radius of influence) LT2 rule (See Long Term Enhanced Surface Water Treatment Rule) Ludzack-Ettinger process (nitrogen removal), 770 LWQA (Lake water quality assessment), 140 Macroinvertebrate biotic index (MBI), 119–120 Macroinvertebrate tolerance list (IEPA), 893–898 Macrophytes: in lake use support analysis, 158–167 in lakes and reservoirs, 141–142, 147, 154 in streams and rivers, 6, 54 Magnesium carbonate hardness, 409, 410 Manganese removal (water supply), 435–440 Manganese zeolite process, 438 Manholes, 564–565 Manning equation, 248–263, 273–276 Manufacturers’ empirical design approach (RBCs), 719–726 Maps, lake, 126–127 Marston’s equation, 572–573 Mass (apparent mass) (m), 228 Mass balance: aeration tank, 654–656 microorganism and substrate, 629–631 secondary clarifier, 657 Mass transfer equation, 213–214 Mass transfer rate, 349–350, 355–356, 454–455 Mass-volume relation (slurry), 799–800 Mattee-Muller model, 355 Maximum contaminant level (MCL, water), 335, 497, 507 932 Index Maximum contaminant level goal (MCLG, water): for carcinogens, 321 for Category I contaminants, 332, 334 for Category II contaminants, 332, 334 for Category III contaminants, 332, 334–335 compliance with standards for, 340–341 development of, 332–335 for disinfectants/disinfectant by-products, 494 federal standards (table), 322–331 for radionuclides, 519–520 Maximum daily flow rate, 316, 420–430 Maximum hourly flow rate, 548, 726 Maximum rate for substrate utilization, 629–630 Maximum specific growth rate, 621, 630, 776–777 Maximum yield coefficient, 630 MBI (See Macroinvertebrate biotic index) MCL (See Maximum contaminant level) MCLG (See Maximum contaminant level goal) Mean cell residence time, 629–631, 657–658, 661, 816 Mean depth: of lake, 127–129, 195 of stream/river, 3, 73 Mean velocity gradient (G), 378–383 Mechanically aerated systems (activated sludge), 688–690 Membrane(s): and disinfection by-products, 502–503 filter method, 114–117 processes, 444–458 description and operations of, 445–449 design considerations for, 449–450 and membrane performance, 450–458 silt density index, 458 treatment strategies, 521 Mercury, 325, 846, 853 Mesotrophic lakes, 157 Metals: in anaerobic digesters, 813 groundwater contamination by, 212 and ion exchange, 418 in land-applied biosolids, 845, 852, 855, 858 screening of, 581 in sludge, 798 in stormwater, 557 Metals (Cont.): in wastewater, 537 in water samples, 140, 142 (See also specific metals) Methane-forming bacteria, 813 Methanes, 345, 729 from anaerobic degradation, 213 in drinking water, 323, 327, 471 in wastewater, 537, 727, 734–735, 813, 816–818 Method of equivalent pipes, 260–261 Methods for lateral radius of influence, 219–222 MF (See Microfiltration) Microbial contaminants (drinking water): federal regulation of, 321, 322, 336–339 and membrane filtration, 449 and source water protection, 495, 496 Micrococcus, 791 Microfiltration (MF), 445, 446, 502–504 Microorganism and substrate mass balance, 629–631 Microthrix parvicella, 663 Mineralization factor (Kmin), 848–849 Minimum daily flow (wastewater), 548 Minimum hourly flow (wastewater), 548 Miscible substances, 216 Mixed liquor suspended solids (MLSS): composition of, 622 MLSS settling test, 642–648 MLVSS vs., 623 Mixed liquor volatile suspended solids (MLVSS), 622, 623 Mixed media filtration, 395 Mixing: public water supply coagulation, 377–380 (See also Aeration) MLSS (See Mixed liquor suspended solids) MLSS settling test, 642–648 MLVSS (See Mixed liquor volatile suspended solids) Modified activated sludge processes, 663–681 biological nitrification, 681 complete-mix process, 554 contact stabilization, 671–672 deep shaft reactor, 679–680 extended aeration, 669–670 Hatfield process, 673 high rate aeration, 671 high-purity oxygen system, 674–677 Index Modified activated sludge processes (Cont.): Kraus process, 673–674 oxidation ditch, 677–679 sequencing batch reactor, 674 short-term aeration, 671 step aeration, 667–668 tapered aeration, 666–667 Modified Ludzack-Ettinger process (nitrogen removal), 770 Modified wetlands, 863 Moisture content (sludge), 800–801, 826, 840 Molar density of water, 346 Molybdenum, 846, 852, 853 Moment method, 19, 23–29 Monochloramine, 468–471 Monod model of population dynamics, 776 Moody diagram, 242, 243, 252, 684 Most probable number (MPN) method (coliform density), 109–117 MPN method (See Most probable number method) Multiport diffusers, 265 Multistage model for carcinogenesis, 517–519 Nanofiltration (NF), 446–447, 502, 503, 505 Nanotubes, 447 National Drinking Water Contaminant Candidate List (CCL), 332 National Pollution Discharge Elimination System (NPDES), 459, 580–581, 842 National Primary Drinking Water Regulations (NPDWRs), 321–331, 494 National Research Council (NRC) trickling-filter formula, 700–705 National Secondary Drinking Water Regulations, 321, 332 National Urban Runoff Program (NURP), 556–557 Natural self-purification in streams, 55–76 apportionment of stream users, 79–86 critical point on oxygen sag curve, 64–76 determination of kr, 62–63 oxygen sag curve, 55–62 simplified oxygen sag computations, 77–78 Natural wetlands, 862 NBOD (See Nitrogenous BOD) 933 Net waste activated-sludge (Px), 633 Newton (N), 228 Newton’s viscosity law, 231 NF (See Nanofiltration) Nickel, 846, 853, 906 Nitrate: drinking water standards for, 325 removal in water supply, 426–434 Nitrate effect on kinetics of nitrification, 793–794 Nitrification: biological, 681, 773–775 combined carbon oxidation-nitrification in attached growth reactors, 786–791 kinetics of, 775–786 loading rate of, 778 and organic loading rate, 778 OWASA process, 766 and pH, 779–780 with rotating biological contactor, 786–791 temperatures for, 778–779 Nitrifying biofilm properties, 775 Nitrobacter, 774–775 Nitrogen: biosolids application calculation based on, 847–851 in wastewater, 537 Nitrogen control (AWT), 772–796 advanced processes for, 772–773 biological nitrification, 773–775 combined carbon oxidation-nitrification in attached growth reactors, 786–791 conventional processes for, 772 denitrification, 791–796 environmental effects of nitrogen compounds, 772 kinetics of denitrification, 793–794 of nitrification, 775–786 nitrifying biofilm properties, 775 Nitrogenous BOD (NBOD), 10, 16, 74–75, 98 Nitrosomonas, 775–780 NOAEL (See No-observed-adverse-effectlevel) Nodal method (distribution networks), 264 Nomograph: for Hazen-William formula, 247 for Manning formula, 250 Nonequilibrium flows (See Unsteady flows) 934 Index Nonisotropic turbulence, 45 Nonvolatile suspended solids, 165 No-observed-adverse-effect-level (NOAEL), 332, 333, 341 Nozzle coefficient (Cv), 294–296 Nozzle meters, 292, 294 Nozzles: public water supply aeration, 365–368 NPDES (See National Pollution Discharge Elimination System) NPDES permits, 459, 842 NPDWRs (National Primary Drinking Water Regulations), 494 NRC formula, 700 NRC trickling-filter formula (See National Research Council tricklingfilter formula) NTUs (See Number of transfer units) Nuclear radiation, 519 Number of transfer units (NTUs), 362 NURP (See National Urban Runoff Program) Nutrient budget (lakes), 171–173 Nutrient removal, 579, 766–772 OBPs (See Ozonation by-products) Observed yield (Yobs), 631, 639 Ocardia, 663l O’Connor and Dobbins equation, 46, 74 Oligotrophic lakes, 157 One-hit (one-stage) model for carcinogenesis, 517 Ontario, 549–550 Open channel water flow, 272–291 Che’zy equation for uniform flow, 272–273 critical depth, 285–287 hydraulic jump, 287–290 Manning equation for uniform flow, 273–276 partially filled conduit, 276–281 self-cleansing velocity, 281–284 specific energy, 284–285 Operation and control of activated sludge, 649–663 aeration tank mass balance, 654–656 return activated sludge, 650–654 secondary clarifier mass balance, 657 sludge age, 657–662 sludge bulking, 662–663 sludge density index, 650 sludge volume index, 649–650 waste activated sludge, 657 Optimum fluoride concentration, 506–507 Organic chemicals (drinking water), 326–330 Organic compounds, Freundlich adsorption isotherm constants for, 909–912 Organic loading rate: and biological nitrification, 778 stabilization ponds, 728–731 Organic matter/material: anaerobic digestion of, 813, 815 and BOD, 10, 14–15, 18–19 critical concentration for, 778 decomposition of, 52–54, 727, 735 and DO saturation, 44–45 in grit chamber, 586 and iron/manganese removal, 435–438 in lakes, 6, 125–126–166, 151–155, 157 metabolism of, 620–622, 682 in sludge, 797, 800, 841, 844–845 stabilization of, 672, 826–827 in streams, 55–56 transfer of, 696 in wastewater, 535–541, 574–579, 626, 633–634, 678, 727 Organic polymers, 827 Organic sludge deposits: and natural self-purification, 55–76 critical point on oxygen sag curve, 64–76 determination of kr, 62–63 oxygen sag curve, 55–62 simplified oxygen sag computations, 77–78 in streams and rivers, 52–54 Orifice discharge, 296–297 Orifice meters, 292, 294 Oscillatoria, 714 Osmosis: definition of, 445 and membrane processes, 444–449 reverse, 445–449, 453–455, 502–504, 521 Osmotic pressure, 445, 448, 450–458 Overall mass transfer coefficient ( KL ): in air, 349 in liquid, 349–350, 355–356, 358–359 Overall use of lake, 165 Overflow rate (water supply sedimentation), 388–390 OWASA nitrification process (phosphorus removal), 767 Index Oxidation, 522 of ammonia, 469–470, 626, 775–777 by chlorination, 464 chlorine dioxide for, 471–472 of domestic sewage, 30 for iron and manganese removal (water), 342–343, 365, 436–440 of nitrites, 774–775 of nitrogenous compounds, 10 for organic matter, 15–16, 635, 666, 783 of protoplasm, 626 of TKN, 634, 784 Oxidation ditch (activated sludge), 677–679 Oxidation ponds (See Stabilization ponds) Oxidation rate: of nitrification, 777, 782 in stream, 32, 49, 52, 55–56 Oxygen: deficiencies in streams and rivers, transfer and utilization of (activated sludge), 681–683 Oxygen requirement for activated sludge, 634–635 Oxygen sag constant, 43–45 Oxygen sag curve: Churchill-Buckingham method, 59–62 critical point on, 64–76 determination of kr, 62–63 natural self-purification in streams, 55–62 simplified computations, 77–78 Thomas method, 59 Oxygen sag formula, Streeter-Phelps, 13–14 Ozonation, 473–474 Ozonation by-products (OBPs), 498, 499 Ozone, 473–474, 491, 492, 498–499 Packed towers, 357–365 PAN (Plant available nitrogen), 849 Pan evaporation, 135–136 Parasites, 322, 842–844 Parshall flume, 302–305, 588 Partially filled conduit, 249, 276, 277 Pascal, 229–231 Pascal’s law, 230 Pathogen reduction regulation (sludge), 842–845 Pathogens (wastewater), 108–109 Paved sludge drying beds, 837–838 PE (Pressure energy), 238 Peak hourly flow (wastewater), 548 Pellet softening (of water), 411–417 935 Percent capture, 809 Percent saturation of DO absorbed per mix, 88 Perfect gas, 234–235 Performance, membrane, 450–458 Permeability (P), 191–195 PFRP (Process to further reduce pathogens), 827 pH: and biofilm densities, 505 and chlorine dioxide, 471–472 and combined available chlorine, 469 and free available chlorine, 464, 465 and nitrification, 779–780 Phelps law, 15–16 Phosphorus: biosolids application calculation based on, 851–852 dissolved, 154–155 in lakes and reservoirs, 154–155 removal (AWT), 753–770, 772 by biological processes, 766–772 by chemical precipitation, 754–766 by lime treatment of secondary effluent, 760–766 by mineral addition to secondary effluent, 759–760 in primary and secondary plants, 755–758 in runoff, 558 in wastewater, 537 PhoStrip process (phosphorus removal), 767 PhoStrip II process (nitrogen removal), 769 Photosynthesis, DO in water and, 54–55 Physical conditioning (sludge), 827–828 Physical properties: of wastewater, 533–537 of water, 233 Pipe network, 258–264 Pipeline systems, 254–258 in parallel, 257–258 in series, 255–257 Pipes: water flow in, 236–264 distribution networks, 258–264 dividing-flow manifolds, 265 fluid pressure, 236 head, 237–253 leakage test for, 320–321 multiport diffusers, 265 pipeline systems, 254–258 sludge flow, 265 936 Index Pitot tube measurement, 291–292 Plant available nitrogen (PAN), 849 Plastic media: for rotating biological contactors, 711 for trickling filters, 705 Plate and frame filter press, 833–836 Plug-flow with recycle (activated sludge), 648–649 Point source dilution, 2–3 Point-of-use units, 520 Poise, 232 Pollutants: biosolids application calculation based on, 852–853 concentrations, 846, 852–853, 858–859 in lakes and reservoirs, 125–126–166 from runoff, 559–562 Population estimates (water supply), 311–315 arithmetic method, 311–312 constant percentage growth rate method, 312–313 declining growth method, 313 logistic curve method, 313–314 Porosity, 184–190, 396–399, 442 Potassium, 853 Potassium dichromate, 540 Potassium permanganate, 376, 436–440, 832 POTW (See Public owned treatment works) Power requirement for mixing, 378–380, 695–696 Power to pump water (PW), 265 Pragmatic approach: steps in, 99–106 stream DO model, 92–106 Precipitation, 551–553, 559–560 Preliminary wastewater treatment systems, 575–576 Pressure (P), 229–231 Pressure energy (PE), 238 Pressure filtration (sludge dewatering), 830–836 Pressure head, 238–239 Primary sedimentation tanks (wastewater), 607–617 Primary wastewater treatment system, 576–577 Process to further reduce pathogens (PFRP), 827 Process to significantly reduce pathogens (PSRP), 826 Pseudomonas, 621, 727 PSRP (Process to significantly reduce pathogens), 826 Public owned treatment works (POTW), 580–581, 796, 842 Public water supply, 308–525 activated carbon adsorption isotherm equations, 440–444 aeration and air stripping, 343–368 diffused aeration, 355–357 gas transfer models, 347–355 nozzles, 365–368 packed towers, 357–365 coagulation, 371–380 disinfection, 463–491 chlorination, 464–473 CT values, 477–491 disinfection by-products, 491–506 disinfection kinetics, 474–475 ozonation, 473–474 filtration, 392–403 hydraulics of filter, 396–401 mixed media, 395 size of filter medium, 394–395 flocculation, 380–384 fluoridation, 506–513 health risks, 513–525 assessment of, 515–520 management of, 520–525 potential of, 514–515 ion exchange, 417–434 leakage, 425–426 nitrate removal, 426–434 iron and manganese removal, 435–440 membrane processes, 444–458 description and operations of, 445–449 design considerations for, 449–450 and membrane performance, 450–458 sild density index, 459 silt density index, 458 population estimates, 311–315 arithmetic method, 312 constant percentage growth rate method, 312–313 declining growth method, 313 logistic curve method, 313–314 residual from water plant, 458–463 sedimentation, 384–392 solubility equilibrium, 368–371 sources and quantity of water, 308–311 washwater troughs, 401–402 Index Public water supply (Cont.): water quality regulation, 321–342 atrazine, 341–342 compliance with standards, 340–341 maximum contaminant level, 335 maximum contaminant level goals, 332–335 National Primary Drinking Water Regulations, 321–331 National Secondary Drinking Water Regulations, 332 Safe Drinking Water Act, 321, 332–335 updates to, 2006, 335–339 water requirements, 315–321 water softening, 404–417 lime-soda, 404–411 pellet, 411–417 water treatment processes, 342–343 Pumping: cost of, 270–272 wastewater treatment, 568–572 water and wastewater, 265–272 wells, 182–183 QUALZE model, 54, 55 Quantity and characteristics of sludge, 796–801 Quantity of wastewater, 545–548 Racks, 581–586 Radionuclides, 330, 519–520 Radius of influence, 219–222 Rainfall (See Precipitation) Rapid methods (ultimate BOD), 32 Rapid ratio method, 19, 32 RAS (See Return activated sludge) RBC (See Rotating biological contactor) RBCs (See Manufacturers’ empirical design approach) Reactors, pellet softening, 411–417 Reaeration, 41–49, 87–92 Reaeration curve, Velz, 87–92 Reaeration rate constant K2, 41–49 Reciprocating pumps, 265 Recirculation, 638, 675, 698 Recreation use impairment index (RUI), 140, 154, 158–168 Rectangular basin design, 612–614 Recycle ratio, 536, 671, 738 Reed-Theriault least-squares method, 19 Reference Dose (RfD) (drinking water contaminants), 332–335, 523 937 Regulations: for biosolids, 831–842 CT values, 477–491 for sludge, 841–861 for water quality, 321–342 (See also Federal drinking water standards) Relationship of sediment and SOD, 51 Relative roughness of pipe wall, 242, 256 Reservoirs (See Lakes and reservoirs) Residual disinfectant concentration, 476, 479 Residual from water plant, 458–463 Residual production and density, 461–462 Residuals (See Sludge) Respiration DO in water, 6, 54–55, 98 Retention time: in activated sludge systems, 658, 664, 716, 779, 820 hydraulic, 478, 627–633, 719 of lake, 128, 130 in secondary tank, 736 of solids, 794 in wastewater treatment, 549, 596, 623, 624 Return activated sludge (RAS), 622, 650–654 Return flow rate, 698 Reverse osmosis (RO), 445–449, 453–455, 502–504, 521 Revised Universal Soil Loss Equation (RUSLE), 174, 175 Reynolds number (R), 188–189 Risk: definition of, 514 potential of, 514–515 Risk assessment, 515–520 Risk management, 520–525 Rivers (See Streams and rivers) RO (See Reverse osmosis) Rotating biological contactor (RBC, wastewater treatment), 711–726 advantages/disadvantages of, 716–717 denitrification with, 794–796 hardware, 712–713 nitrification with, 786–791 process description, 713–716 process design, 718–726 soluble BOD5, 718 RUI (See Recreation use impairment index) 938 Index Runoff, 551–553 estimation of, 555–556 models, 559–562 National Urban Runoff Program, 556–557 rainfall intensity, 552–553 street and road loading rate, 559–560 time of concentration, 554 (See also Stormwater) RUSLE (See Revised Universal Soil Loss Equation) Safe Drinking Water Act (SDWA), 217, 321, 332–336, 496, 503, 507 Salmonella, 842–844 Salt flux, 451–452 Sand seeding (in pellet softening), 412, 416–417 Sand sludge drying beds, 836–837 SBOD (Suspended BOD), 718 SBRs (See Sequencing batch reactors) Scour, 593–595 Screening devices (wastewater), 581–586 SDI (Silt density index), 458 SDWA (See Safe Drinking Water Act) Secchi disc transparency, 153–154 Second-order reaction, 37–41 Secondary clarifiers/sedimentation tanks (wastewater), 735–742 basin sizing for attached-growth biological treatment effluent, 736–739 for suspended-growth biological treatment, 739–742 mass balance, 657 Secondary (biological) treatment systems, 578, 617–621 Sediment budget (lakes), 171–173 Sediment oxygen demand (SOD), 49–52 dissolved oxygen vs., 51–52 in DO usage, 78–79 Sedimentation: public water supply, 384–392 inclined settlers, 390–392 overflow rate, 388–390 wastewater treatment, 592–607 compression settling (type 4), 606–607 discrete particle sedimentation (type 1), 592–593 flocculant settling (type 2), 600–602 hindered sedimentation (type 3), 602–606 scour, 593–595 Sedimentation tanks (wastewater): configuration of, 595–600 primary, 607–617 secondary, 735–742 sludge from, 797–798 Seeding sand (in pellet softening), 412, 416–417 Selenium, 325, 846, 853 Self-cleansing velocity, 281–284 Self-purification (See Natural selfpurification in streams) Semipermeable membranes, 445, 447 Separated sewer systems, 542–543 Sequencing batch reactors (SBRs), 622, 674 Setback zones (groundwater protection), 217–218 Settleable solids (wastewater), 535 Settling velocity: in wastewater treatment, 592–606, 608, 642, 735, 737 in water supply, 385–388, 395, 399 7-day, 10-year flow, 3–4 Sewage (See Wastewater) Sewage sludge (See Biosolids) Sewers/sewer systems, 542–543 appurtenances, 562–568 buried, 572–574 combined sewers, 543–544 construction of, 572–574 depressed (inverted siphons), 565–568 hydraulics for, 562 inverted siphons (depressed sewers), 565–568 manholes, 564–565 self-cleansing velocity in, 281–284 separated systems, 542–543 street inlets, 562–564 Shannon-Weiner diversity index, 107–108 Shoreline development index, 127–129 Short-term aeration (activated sludge), 671 Silicon tetrafluoride, 507–508 Silt density index (SDI, water), 458 Simplified oxygen sag computation, 77–78 Site evaluation and selection (biosolids application), 847 Slope: of energy gradient line, 246, 273 vegetated submerged bed system design, 878, 879 Slope method, 19–23 SLR (See Sludge loading ration) Index Sludge (residuals), 796–861 activated, 618 age, 635, 658–662, 671, 820 collector, 612–613 conditioning, 827–828 dewatering, 828–840 centrifugation, 836 pressure filtration, 830–836 sludge drying beds, 836–840 sludge drying lagoons, 839–840 vacuum filtration, 828–830 flow in pipes, 265, 636, 796–809 lime, 798, 839 loading rate, 831, 836–837 mass-volume relation, 799–800 moisture content, 800–801 from primary/secondary/tertiary processes, 797–798 production of, 633 public water supply, 458–463 quantity/characteristics of, 796–801 regulatory requirements, 841–861 land applications, 845–861 pathogen reduction, 842–845 settleability, 649–655, 671, 740 sewage sludge biosolids, 840–841 stabilization, 812–827 aerobic digestion, 820–826 anaerobic digestion, 812–815 composting, 826–827 egg-shaped digesters, 820 gas production, 815–820 lime stabilization, 826 thickening, 802–812 centrifuge, 807–811 dissolved air flotation, 805–807 gravity, 802–805 gravity belt, 811–812 treatment alternatives, 801 types of, 458–459 use/disposal of sewage sludge biosolids, 841 volume reduction processes, 828–840 wasting, 627–628, 657, 670, 674 Sludge age, 657–662 Sludge bulking, 662–663 Sludge density index (SDI), 650 Sludge drying beds, 836–840 Sludge drying lagoons, 839–840 Sludge loading ration (SLR), 624 (See also Food-to-microorganism ratio) Sludge volume index (SVI), 649–650 Slug tests (unsteady flows), 206–211 Slugs (mass), 228 939 Small systems (water supply), 503–504 SO2 (Sulfur dioxide), 746 SOD (See Sediment oxygen demand) Soda ash (lime), 404–411 Sodium fluoride, 507 Sodium hydroxide, 822 Sodium hypochlorite, 743, 744 Sodium metabisulfite (dechlorination), 746 Sodium silicofluoride, 507, 508 Soil loss rate (lakes), 173–176 “Sole Source Aquifer Demonstration program,” 495 Solids: capture, 380, 581, 809, 833, 836 content, 265, 533–534, 607, 797–800, 802–803, 811, 821, 826–827, 830, 837, 839, 844–845 flux, 642–644 loading rate, 606, 740–741, 802, 806–807, 814, 821–828, 840 retention time, 650, 658, 779, 820 in wastewater, 533–537 Solubility: equilibrium, 368–371 of gas, 343, 350, 352 at or near room temperature, 904–907 of ozone, 473–474 product constants, 904–907 Solubility equilibrium, 368–371 Solubility product constant (Ksp), 368–371 Soluble biodegradable substrate, 626 Soluble BOD5, 718 Solutions, at or near room temperature, 904–907 Sorption (groundwater), 213–214 Source water protection (SWP), 495–497 Sources and quantities of water, 308–311 Soybeans, 327, 854 Specific capacity (groundwater), 195 Specific energy (He), 284–285 Specific substrate utilization rate, 632 Specific weight (g, w), 228–229 Sphaerotilus, 714 Spillways, weir coefficients of, 94–95 Spores, 501 Stabilization ponds (wastewater), 726–734 aerobic, 734–735 anaerobic, 735 classifications of, 726–727 facultative, 727–735 Stage Disinfectants and Disinfection By-products Rule, 335–338, 493 940 Index State EPA, 321, 332 State lake classification survey, 139–140 Stationary field monitoring procedure, 46–49 Steady flows (groundwater), 195–196 Step aeration (activated sludge), 667–668 Stoke, 233 Stokes equation for laminar flow conditions, 386 Stoke’s law, 386–388, 593, 608 Storage tank, leaking, 521 Storativity (S) (groundwater), 185 Cooper-Jacob method, 201–204 distance-drawdown method, 204–206 slug tests, 206–211 Theis method, 198–201 Storm sewers, 542–543 Stormwater: event mean concentration, 556–559 National Urban Runoff Program, 556–557 quality of, 556–559 runoff models, 559–562 storm drainage system design, 551 street and road loading rate, 559–560 (See also Runoff ) Stormwater management, 549–551 Stream DO model, 92–106 DO used, 98 influence of dams, 92–95 influence of tributaries, 95–97 steps of pragmatic approach, 99–106 Streams and rivers, 1–120 apportionment of stream users, 79–86 biochemical oxygen demand analysis, 10–13 biological factors, 107–108 algae, 107–108 indicator bacteria, 108–120 macroinvertebrate biotic index, 119–120 BOD models and K1 computation, 14–41 deoxygenation rate and ultimate BOD, 18–32 first-order reaction, 15–18 second-order reaction, 37–41 temperature effect on K1, 32–37 discharge measurement, 3–4 dissolved oxygen and water temperature, 5–9 Streams and rivers (Cont.): natural self-purification in streams, 55–76 critical point on oxygen sag curve, 64–76 determination of kr, 62–63 simplified oxygen sag computations, 77–78 organic sludge deposits, 52–54 point source dilution, 2–3 reaeration rate constant K2, 41–49 runoff to, 308–311 sediment oxygen demand (SOD), 49–52, 78–79 stream DO model, 92–106 influence of dams, 92–95 influence of tributaries, 95–97 steps of pragmatic approach, 99–106 Streeter-Phelps oxygen sag formula, 13–14 time of travel, 4–5 Velz reaeration curve, 87–92 Street and road loading rate (runoff), 559–560 Street inlets, 562–564 Streeter-Phelps oxygen sag formula, 13–14 Streptomyces, 714 Substrate limited growth, 620–621 Substrate utilization rate (rsu), 539, 630, 632 Subsurface flow wetlands (See Vegetated submerged bed (VSB) systems) Sulfur dioxide (SO2), 746 Sulfuric acid (in pellet softening), 412, 416 Supersaturation (DO), Supervisory control and data aquisition systems, 504 Supplemental potassium (K) fertilizer, 853–861 Surface (overflow) loading rate, 388–392, 722, 753 Surface settling rate, 609–611 Surface tension, 688 Surface Water Treatment Regulations (SWTR), 340, 476 Surfact process, 716 Suspended BOD (SBOD), 718 Suspended solids effluent standards, 79, 534, 617–618, 753 Suspended solids removal, 753 Index Suspended-growth biological treatment, 627, 739–742 SVI (See Sludge volume index) Swimming, 117, 162 SWP (See Source water protection) SWTR (See Surface Water Treatment Regulations) Synthesis denitrification, 791–793 Tap water, 521 Tapered aeration (activated sludge), 666–667 TARP (Tunnel and Reservoir Plan), 550 TBOD (Total BOD), 718 TC (See Total coliform) TDS (See Total dissolved solids) Temperature(s): and deoxygenation coefficient, 14–15 for nitrification, 778–779 of wastewater, 533 Temperature correction factor: Arrhenius model for, 474 for gases, 345 in RBC, 722, 788 Ten States Recommended Standards for Sewage Works, 575 Terminal settling velocity (sedimentation), 385–388 Tertiary stabilization ponds, 734 Theis method, 198–201 Thermal conditioning (sludge), 827–828 Thiotrix, 663, 717 THMs (See Trihalomethanes) Thomas method, 59 Time: of concentration, 554 of travel, 4–5, 183 Time-related capture zones, 183 TOC (See Total organic carbon) TOD (Total oxygen demand), 10 Toluene (in drinking water), 328 Total BOD (TBOD), 718 Total coliform (TC), 109, 146 Total dissolved solids (TDS, wastewater), 447, 452–456, 534, 579 Total energy head, 256, 284 Total organic carbon (TOC), 10, 156, 427, 499, 500, 535 Total oxygen demand (TOD), 10 Total phosphorus (TP), 154–155 Total solids (TS, wastewater), 534 Total suspended solids (TSS, wastewater), 534, 579 941 Total volatile solids, 537 Toxic organic compounds, 909–912 TP (See Total phosphorus) Transmissivity (T) (groundwater), 185–186 Cooper-Jacob method, 201–204 distance-drawdown method, 204–206 in flow nets, 186–187 slug tests, 206–211 Theis method, 198–201 Treatment cost, 87, 126, 168–173 Treatment strategies, 521–525 Treatment technique (TT), 335 Tributaries, dissolved oxygen and, 95–97 Trichloramine, 468 Trickling filter (wastewater treatment), 853–861 design formulas, 698–711 distributor speed, 707–711 Eckenfelder formula, 705–706 Germain formula, 707 NRC formula, 700–705 for plastic media, 705 filter classification, 698 process description, 696–698 recirculation, 698 sludge from, 797 Trihalomethanes (THMs), 337, 339, 492–494 Triple-sludge process (nitrogen removal), 773 Trophic state index (TSI, lakes), 156–159 TS (Total solids), 534 TSI (See Trophic state index) TSS (See Total suspended solids) TT (Treatment technique), 335 Tunnel and Reservoir Plan (TARP, Chicago), 550 Turbidity: and LT2 rule, 337 maximum contaminant level goal for, 322 and membrane filtration, 449 and microfiltration, 445 Two-film theory (gas transfer), 347–355 Two-resistance layer theory (diffused aeration), 355–356 Type curve, 199–200 carbonaceous, 34 nitrogenous, 34 942 Index UBOD (See Ultimate (total) BOD) Ultimate (total) BOD (UBOD), 18–32 logarithmic formula, 30–32 moment method, 23–29 rapid methods, 32 slope method, 19–23 Ultrafiltration (UF), 445–446, 502–504 Ultraviolet (UV) radiation, 463, 497, 499, 742, 747 Uncertainty factor, 332–333, 341 Unconfined aquifers, 180–181 Bouwer and Rice slug test for, 208–209 defined, 180 flows in, 195–196 lateral area of influence, 218–219 storativity in, 185–186 volumetric flow equation, 223 well discharge for, 192–193 Underground storage tanks (USTs), 214–216, 521 Uniform coefficient, 393, 419 Uniform flow, 272–273 Universal Soil Loss Equation (USLE), 174, 175 Unpaved sludge drying beds, 838 Unsteady (nonequilibrium) flows (groundwater), 198–211 Cooper-Jacob method, 201–204 distance-drawdown method, 204–206 slug tests, 206–211 Theis method, 198–201 Uranium, 330, 519, 520 Urban stormwater management, 549–551 US Environmental Protection Agency (EPA): atrazine concentration, 342 carcinogen classification scheme of, 333–334 Clean Lakes Program, 137–138, 156 cost-benefit analysis, 335 fluoride standards, 507 iron standards, 435 Long Term Enhanced Surface Water Treatment Rule, 335, 337–339 manganese standards, 435 maximum contaminant level goal, 340 Part 503 rule, 841–842, 847 particle removal times, 559 public wells, 183 QUALZE water quality model, 55 and risk assessment/management, 518, 522 Safe Drinking Water Act, 321 US Environmental Protection Agency (EPA) (Cont.): Stage Disinfectants and Disinfection By-products Rule, 335–338 Surface Water Treatment Regulations, 475 uncertainty factor determination, 332–333 wellhead protection programs, 217 wetlands, 862 Use and disposal of sewage sludge biosolids, 841 USLE (See Universal Soil Loss Equation) USTs (See Underground storage tanks) UV radiation (See Ultraviolet radiation) Vacuum filtration (sludge dewatering), 828–830 Vacuum-assisted sludge drying beds, 838 Van der Waals force, 372 Vapor pressure, 135, 212, 216, 465 Vegetated submerged bed (VSB) systems, 863, 864, 876–884 Velocity (flow): in open channel, 291 in pipes, 291–292 self-cleansing, 281–284 Velocity coefficient of nozzle, 365 Velocity head, 237–238 Velz reaeration curve, 87–92 Venturi meter, 292–294 Vinyl chloride (in drinking water), 330, 524 VIP process, 768 Viruses: in biosolids, 842–844 in drinking water, 322 enteric, 742, 842–844 filtration of, 393 inactivation of, 475–485, 489–491 (See also CT values) secondary treatment for, 578 sources of, 108–109 ultrafiltration of, 445, 446 in wastewater, 541 Viscosity: absolute, 231–232 kinematic, 233 of water, 231–234 VLMP (See Volunteer lake monitoring program) VOCs (Volatile organic compounds), 212 Index Void ratio, 184, 698 Volatile organic compounds (VOCs), 212 Volatile solids (wastewater), 535 Volatile suspended solids, 140, 535–537, 623, 775, 820 Volatilization factor, 849 Volume development ratio, 128–129 Volume of lake, 127 Volumetric flow equations, 219–223 Volunteer lake monitoring program (VLMP), 139 VSB systems (See Vegetated submerged bed systems) WAS (See Waste activated sludge) Washwater troughs (water supply), 401–403 Waste activated sludge (WAS), 653, 657 Wastewater, 531–884 biological characteristics of, 541–542 BOD analysis of, 10–13 chemical constituents of, 537–541 defined, 533 design flow rates, 547–548 effluent standards for, 79 and oxygen resources of streams, 52–53 pathogens from, 108–109 physical properties of, 533–537 precipitation and runoff, 551–553 quantity of, 545–548 sewer construction, 572–574 sewer hydraulics, 562 sewer systems, 542–543, 562–568 storm drainage system design, 551 stormwater quality, 556–562 and ultrafiltration, 446 urban stormwater management, 549–551 Wastewater lagoons (See Facultative stabilization ponds) Wastewater treatment: activated-sludge process, 621–696 aeration and mixing systems, 681–683 aeration periods and BOD loadings, 623 biochemical reactions, 626 food-to-microorganism (F/M) ratio, 623–626 mathematical modeling of, 627–649 modified processes, 663–681 943 Wastewater treatment, activated-sludge process (Cont.): operation and control of, 649–663 process design concepts, 626–627 advanced, 578–579, 752–796 nitrogen control, 772–773 phosphorus removal, 753–770, 772 suspended solids removal, 753 comminutors, 586 compliance standards, 580–581 dual biological treatment, 726 effluent disinfection, 742–752 chlorine dosage, 743–746 dechlorination, 746–747 process design, 747–752 flow equalization, 588–591 grit chamber, 586–588 preliminary, 575–576 primary (physical), 576–577 primary sedimentation tanks, 607–617 circular basin design, 614–617 rectangular basin design, 612–614 pumping stations, 568–572 rotating biological contactor, 711–726 advantages/disadvantages of, 717 hardware, 712–713 process description, 713–716 RBC process design, 718–726 soluble BOD5, 718 screening devices, 581–586 secondary clarifier, 735–742 secondary (biological) systems, 578, 617–621 sedimentation, 592–607 compression settling (type 4), 606–607 discrete particle sedimentation (type 1), 592–593 flocculant settling (type 2), 600–602 hindered sedimentation (type 3), 602–606 scour, 593–595 sedimentation tank (basin) configuration, 595–600 sludge treatment and disposal, 796–861 quantity/characteristics of sludge, 796–801 regulatory requirements, 841–861 944 Index Wastewater treatment, sludge treatment and disposa (Cont.): sewage sludge biosolids, 841 sludge conditioning, 827–828 sludge dewatering, 828–840 sludge stabilization, 812–827 sludge thickening, 802–812 treatment alternatives, 801 use and disposal of sewage sludge biosolids, 841 stabilization ponds, 726–734 aerobic, 734–735 anaerobic, 735 facultative, 727–735 systems for, 560–562 tertiary (combination), 578–579 trickling filter, 696–711 design formulas, 698–711 filter classification, 698 process description, 696–698 recirculation, 698 and wetlands, 861–884 Water: clarity, Secchi disc transparency for, 153–154 drinking (See Drinking water) fluoridation of, 506–513 groundwater (See Groundwater) physical properties of, 233 public water supply (See Public water supply) viscosity of, 231–234 Water budget method (lake evaporation), 132 Water flow: in open channels, 272–291 Che’zy equation for uniform flow, 272–273 critical depth, 285–287 hydraulic jump, 287–290 Manning equation for uniform flow, 273–276 partially filled conduit, 276–281 self-cleansing velocity, 281–284 specific energy, 284–285 in pipes, 236–264 distribution networks, 258–264 dividing-flow manifolds, 265 fluid pressure, 236 head, 237–253 multiport diffusers, 265 Water flow, in pipes (Cont.): pipeline systems, 254–258 sludge flow, 265 Water flux, 451–452 Water hardness: classification for, 404 lime-soda softening for, 404–411 pellet softening for, 411–417 Water hyacinth, 862–863 Water quality: Clean Lakes Program, 137–176 federal drinking water standards, 321–342 lakes and reservoirs, 130–131, 146–156 Water quality models, 55–56, 130–131 Water requirements, 315–321 fire demand, 315–320 leakage test, 320–321 Water softening, 404–417 lime-soda, 404–411 pellet, 411–417 Water table, 180 Water temperature: and dissolved oxygen, 5–9 in lakes and reservoirs, 148–150 Water treatment processes, 342–343 and disinfection, 491 Watershed management: for drinking water quality, 321 source water protection, 495, 496 Watershed protection approach (WPA), 146 Wedge-wire (wedgewater) sludge drying beds, 838–839 Wehner-Wilhelm equation, 732–734 Weight (W), specific, 228–229 Weir coefficients, 94–95 Weir loading, 388, 390, 608–617 Weirs, 297–302 Well function of u (W(u)), 198–201 “Wellhead Protection Program,” 496 Wells, 183–184, 195 Wells, interceptor, 521 Wetlands, 861–884 aquatic plant systems in, 862–863 constructed, 863–884 environmental/health considerations, 864–866 free water surface wetlands, 866–876 vegetated submerged bed systems, 876–884 Index Wetlands (Cont.): defined, 861 modified, 863 natural, 862 Wheat field, 855–861 Whole effluent toxicity, 580 WPA (Watershed protection approach), 146 Wuhrmann process (nitrogen removal), 769 Zeolites, 418, 438 Zinc, 557, 846, 853, 907 Zocloea, 714 Zone of capture (ZOC, groundwater), 183–184 Zones of influence (groundwater), 183–184 Zoogleoa, 727 945 ... operators, engineers, and managers of water and/ or wastewater treatment plants; and other professionals, such as chemists and biologists, who need some knowledge of water/ wastewater issues This work... and practical examples are given The text includes calculations for surface water, groundwater, drinking water treatment, and wastewater engineering Chapter comprises calculations for river and. .. supply distribution systems and hydraulics for water and wastewater treatment plants are also included Chapters and cover the unit process for drinking water and wastewater treatment, respectively