Water distribution system handbook (part 1)

WATER DISTRIBUTION SYSTEMS HANDBOOK Larry W Mays, Editor in Chief Department of Civil and Environmental Engineering Arizona State University Tempe, Arizona McGraw-Hill New York • San Francisco • Washington, D.C • Auckland • Bogota • Caracas • Lisbon • London • Madrid • Mexico City • Milan • Montreal • New Delhi • San Juan • Singapore • Sydney • Tokyo • Toronto http://www.nuoc.com.vn Library of Congress Cataloging-in-Publication Data Water distribution systems handbook/Larry W Mays, ed p cm Includes bibliographical references ISBN 0-07-134213-3 Water—Distributions Hanbooks, manuals, etc Water—supply engineering Handbooks, manuals, etc I Mays, Larry W TD481.W375 1999 628 1'44—dc21 99-16987 CIP McGraw-Hill ^n A Division of The McGraw-Hill Companies i>6 Copyright © 2000 by The McGraw-Hill Companies, Inc All rights reserved Printed 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 data base or retrieval system, without the prior written permission of the publisher DOC/DOC 043210 ISBN 0-07-134213-3 The sponsoring editor for this book was Larry Hager and the production supervisor was Sherri Souffrance It was set in Times Roman by Compuvision Printed and bound by R R Donnelley & Sons Company This book was printed on acid-free paper McGraw-Hill books are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate training programs For more information, please write to the Director of Special Sales, McGraw-Hill, Inc., Two Penn Plaza, New York, NY, 10121-2298 Or contact your local bookstore Information contained in this work has been obtained by The McGraw-Hill Companies, Inc ("McGraw-Hill") from sources believed to be reliable However, neither McGraw-Hill nor its authors guarantee the accuracy or completeness of any information published herein, and neither McGraw-Hill nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information This work is published with the understanding that McGraw-Hill and its authors are supplying information but are not attempting to render engineering or other professions) services If such services are required, the assistance of an appropriate professional should be sought http://www.nuoc.com.vn CONTRIBUTORS Bayard Bosserman II Boyle Engineering Corporation (CHAPTER 5) Francious Bouchart Heriot-Watt University (CHAPTER 18) Donald V Chase University of Dayton (CHAPTER 15) Robert Clark U S Environmental Protection Agency (CHAPTER 13) Edwin E Geldreich Consulting Microbiologist (CHAPTER 9) Fred E Goldman Goldman, Toy, and Associates (CHAPTER 16) Ian Goulter Swinburne University of Technology (CHAPTER 18) Walter M Grayman Consulting Engineer (CHAPTER 9, 11) Bryan W Karney University of Toronto (CHAPTER 2) Gregory J Kirmeyer Economic and Engineering Services, Inc (CHAPTER 11) Kevin Lansey University of Arizona (CHAPTER 4, 7) Srinivasa Lingireddy University of Kentucky (CHAPTER 14) James W Male University of Portland (CHAPTER 17) C Samuel Martin Georgia Institute of Technology (CHAPTER 6) Larry W Mays Arizona State University (CHAPTER 1,4, 16, 18) Lindell E Ormsbee University of Kentucky (CHAPTER 14, 16) Lewis A Rossman U S Environmental Protection Agency (CHAPTER 9, 12) A Burcu Altan Sakarya Middle East Technical University (CHAPTER 16, 18) Yeou-Koung Tung Hong Kong University of Science and Technology (CHAPTER 18) Jim Uber University of Cincinnati (CHAPTER 16) Thomas M Walski Pennsylvania American Water Co (CHAPTER 8, 10, 17, 18) Mark Ysusi Montgomery Watson (CHAPTER 3) http://www.nuoc.com.vn PREFACE At the beginning of year 2000 this is an exciting time to be involved in writing about the delivery of safe drinking water Today's increased awareness and concern for safe drinking water on a national and international basis, coupled with limited budgets of not only developing countries but also of developed countries, has generated an exponential increase in interest in the future of water distribution In the U S and in other developed countries the populations take the ability to have safe drinking water at any time and place for granted According to the World Health Organization and the United Nations, however, the needs for urban water and rural water supply are tremendous The urban population in developing countries in 1990 without access to safe drinking water was approximately 243 million people, and in rural areas in developing countries was approximately 989 million people, for a total of 1,232 million people without access to safe drinking water The expected population increase in urban areas in developing countries from year 1990 to 2000 is expected to be 570 million people, making the total in urban areas requiring the service of safe drinking water to be 813 million people The expected population increase in rural areas in developing countries from 1990 to 2000 is expected to be 312 million people, making the total in rural areas requiring the service of safe drinking water to be 1,301 million people The total population needs in developing countries requiring safe drinking water by year 2000 is 2,114 million people The Water Distribution Systems Handbook, referred to herein as the Handbook, has been an extensive effort to develop a comprehensive reference book on water distribution systems A substantial amount of new knowledge concerning the design, operation, and analysis of water distribution systems has accumulated over the past decade In particular, many new developments have taken place on the subjects of water quality of storage, modeling of water quality, optimal operation, reliability of water distribution systems, and many other subjects Some of this information is dispersed in professional and scientific journals and reports Within the Handbook the various authors have synthesized this accumulated knowledge and presented it in a concise and accessible form There are obviously many other topics that could have been covered, making the Handbook even more comprehensive; however, I had to make choices on the coverage These choices obviously reflect my vision of what is needed most in the Handbook The topics covered are the ones that I feel are the most important for state-of-the art design, analysis, modeling, and operation of water distribution systems The detail of each topic is fairly well balanced among the chapters and among the topics in each chapter There is also a reflection of my perspective on the subject, with the constraint that all the material fits within one handbook Hopefully, the readers will have an understanding and appreciation of what is being accomplished in this Handbook First and foremost this handbook is intended to be a reference for those wishing to expand their knowledge of water distribution systems The Handbook will be of value to engineers, managers, operators, and analysts involved with the design, http://www.nuoc.com.vn analysis, operation, maintenance, and rehabilitation of water distribution systems This handbook can also be a valuable reference, if not the text in both undergraduate and graduate courses for teaching the design and analysis of water distribution systems Each of the authors is a leading expert in the field of water distribution systems They have published extensively in the literature on water distribution systems, and many of them have had extensive experience in the design, operation, and analysis of distributions systems Each of the authors was chosen because of their proven knowledge in the specific area of contribution As editor in chief of the Handbook, I felt that it was important to provide a brief historical perspective (Chapter 1) of the knowledge of water distribution, starting from the ancient times to the present This historical perspective begins with the pressurized water distribution systems at Knossos (circa 2000 BC) and provides examples of other ancient water systems The developments during the 19th and 20th centuries are particularly important to understand our present status at the start of year 2000 with this handbook in place To better understand where we are and where we may be going, it is wise to look at where we have been In 1952 Albert Einstein was offered the presidency of Israel but declined because he thought he was too naive in politics Perhaps his real reason, according to Stephen W Hawking (A Brief History of Time), was different To quote Einstein, "Equations are more important to me, because politics is for the present, but an equation is something for eternity." Hopefully, this handbook is not only for the present, but also will be a contribution for the future Each book that I have worked on has been a part of my lifelong journey in water resources The Handbook certainly is no exception I have gained more from this experience than can ever be measured in words I dedicate this handbook to humanity and human welfare Larry W Mays Scottsdale, Arizona http://www.nuoc.com.vn Acknowledgments I must first acknowledge the authors who made this handbook possible It has been a sincere privilege to have worked with such an excellent group of dedicated people They are all experienced professionals who are among the leading experts in their fields References to material in this handbook should be attributed to the respective chapter authors During the past twenty-three years of my academic career as a professor, I have received help and encouragement from so many people that it is not possible to name them all These people represent a wide range of universities, research institutions, government agencies, and professions To all of you I express my deepest thanks I would like to acknowledge Arizona State University, especially the time afforded me to pursue this handbook I sincerely appreciate the advice and encouragement of Larry Hager of McGraw-Hill throughout this project Larry has always been a great guy to work with on the three handbooks that we have done together He is always a joy to talk to, as he's one of the few that is willing to listen to my fly fishing and snow skiing experiences This handbook has been a part of a personal journey that began years ago when I was a young boy with a love of water Books are companions along the journey of learning I hope that you will be able to use this handbook in your own journey of learning about water Have a happy and wonderful journey Larry W Mays http://www.nuoc.com.vn ABOUT THE EDITOR Larry W Mays is professor of civil and environmental engineering at Arizona State University and former chair of the department He was formerly director of the Center for Research in Water Resources at the University of Texas at Austin, where he also held an Engineering Foundation Endowed Profesorship A registered professional engineer in seven states and a registered professional hydrologist, he has served as a consultant to many organizations A widely published expert on water resources, he wrote Optimal Control of Hydrosystems (Marcel Dekker) and was editor in chief of both Water Resources Handbook (McGraw-Hill) and Hydraulic Design Handbook (McGraw-Hill) Co-author of both Applied Hydrology and Hydrosystems Engineering and Management published by McGraw-Hill and was the editor in chief of Reliability Analysis of Water Distribution Systems (ASCE), and co-editor of Computer Modeling of Free-Surface and Pressurized Flows (Kluwer Academic Publishers) He has published extensively on his research in water resources management http://www.nuoc.com.vn Contents Contributors xx Preface xxi Acknowledgments xxiii About the Editor xxiv Introduction 1.1 1.1 Background 1.1 1.2 Historical Aspects of Water Distribution 1.3 1.2.1 Ancient Urban Water Supplies 1.3 1.2.2 Status of Water Distribution Systems in the 19th Century 1.9 1.3 1.2.3 Perspectives on Water Distribution Mains in the United States 1.10 1.2.4 Early Pipe Flow Computational Methods 1.16 Modern Water Distribution Systems 1.16 1.3.1 The Overall Systems 1.16 1.3.2 System Components 1.20 1.3.3 System Operation 1.26 1.3.4 The Future 1.29 References 1.30 http://www.nuoc.com.vn This page has been reformatted by Knovel to provide easier navigation v vi Contents Hydraulics of Pressurized Flow 2.1 2.1 Introduction 2.1 2.2 Importance of Pipeline Systems 2.2 2.3 Numerical Models: Basis for Pipeline Analysis 2.3 2.4 Modeling Approach 2.4 2.4.1 Properties of Matter (What?) 2.5 2.4.2 Laws of Conservation (How?) 2.6 2.4.3 Conservation of Mass 2.4.3.1 Law of Conservation of Chemical Species 2.4.3.2 Steady Flow 2.7 Newton's Second Law 2.9 2.4.4 2.7 2.8 2.5 System Capacity: Problems in Time and Space 2.10 2.6 Steady Flow 2.13 2.6.1 Turbulent Flow 2.15 2.6.2 Headless Caused by Friction 2.16 2.6.3 Comparison of Loss Relations 2.18 2.6.4 Local Losses 2.21 2.6.5 Tractive Force 2.22 2.6.6 Conveyance System Calculations: Steady Uniform Flow 2.23 2.6.7 Pumps: Adding Energy to the Flow 2.26 2.6.8 Sample Application Including Pumps 2.28 2.6.9 Networks - Linking Demand and Supply 2.30 2.7 Quasi-Steady Flow: System Operation 2.30 2.8 Unsteady Flow: Introduction of Fluid Transients 2.32 2.8.1 Importance of Waterhammer 2.32 2.8.2 Cause of Transients 2.34 http://www.nuoc.com.vn This page has been reformatted by Knovel to provide easier navigation 2.8.3 Contents vii Physical Nature of Transient Flow 2.8.3.1 Implication Water Has a High Density 2.8.3.2 Implication Water is Only Slightly Compressible 2.8.3.3 Implication Local Action and Control of Valves 2.35 2.35 2.35 2.36 2.8.4 Equation of State-Wavespeed Relations 2.37 2.8.5 Increment of Head-Change Relation 2.38 2.8.6 Transient Conditions in Valves 2.8.6.1 Gate Discharge Equation 2.8.6.2 Alternate Valve Representation 2.8.6.3 Pressure Regulating Valves 2.8.7 Conclusion 2.42 2.39 2.40 2.41 2.42 References 2.42 System Design: An Overview 3.1 3.2 3.1 Introduction 3.1 3.1.1 Overview 3.1 3.1.2 Definitions 3.2 Distribution System Planning 3.2 3.2.1 Water Demands 3.2 3.2.2 Planning and Design Criteria 3.2.2.1 Supply 3.2.2.2 Storage 3.2.2.3 Fire Demands 3.2.2.4 Distribution System Analysis 3.2.2.5 Service Pressures 3.7 3.7 3.7 3.8 3.8 3.8 3.2.3 Peaking Coefficients 3.9 http://www.nuoc.com.vn This page has been reformatted by Knovel to provide easier navigation V2 V2 30 20 TJ — nfJ -4- Tf ° 4- Jf 20 ° L L 300 mm ^ A300 2o ° 2# n = #L300mm+1.96^ + 0.25^ = 3.10 o Z^ 2.31 [ (10/12)4 J Q 2g K = 0.12058 G2 V12 V?0 Vl Total #L = HL 12in + #L loin + A^12 -TT+ JT10 -^+ ^8 ^T = 0.013139 Q185 + 0.015936 G185 + 0.04933 G2 + 0.12058 G2 + 0.031859 G2 = 0.0291 G185 + 0.202 G2 Part Modification of Pump Curve Using the above equation for H1, a "modified" pump curve can then be developed by converting pump curve head values to include minor piping losses: H (ft) G GPM CFS Uncorrected O 1000 2000 3000 4000 0.000 2.228 4.456 6.684 8.912 200 180 160 130 90 Corrected 200.00 178.87 151.52 120.0 72.29 The H values, as corrected, must then be plotted The operating point of the pump is the intersection of the corrected H-Q curve with the system curve Part Calculation of NPSHA Using the data developed above for calculating the minor losses in the piping, it is now possible to calculate the NPSH4 for the pump Only the minor losses pertaining to the suction piping are considered: Items 1-8 in Fig 5.12 For this suction piping, we have: Kn = 1.96, KZ = 0.25, sum of C values Pipe length for 12-in pipe: L = 26 ft Determine the headless in the suction piping: y2 H L = H K L i2in + u "TJT y2 + ^s 2^ = ^,2,+ 1-96 ^ + 0.25 ^ http://www.nuoc.com.vn = 0.013139 G185 + 0.0493322 + 0.031859Q2 = 0.013139 G185 + 0.081189g2 For Fig 5.12, assume that the following data apply: High-water level = elevation 2241 ft Low-water level = elevation 2217 ft Pump center line elevation = 2212 ft Therefore, Maximum static head = 2241 - 2212 = 29 ft Minimum static head = 2217 - 2212 = ft Per Eq (5.31), NPSHA = hatm + hs - hvp - hL For this example, use the following: hatm= hvp = hs = hs = 33.96ft 0.78 ft at 6O0F 29 ft maximum ft minimum Compute NPSHA: Condition High-static suction head Low-static suction head Flow hs hatm hvp (ftVs) (ft) (ft) (ft) (ft) (ft) 29 33.96 0.78 0.00 62.18 O HL at Flow NPSHA at Flow 29 33.96 0.78 0.37 61.81 29 33.96 0.78 1.47 60.71 29 33.96 0.78 3.28 58.90 29 33.96 0.78 5.81 56.37 10 29 33.96 0.78 9.05 53.13 O 33.96 0.78 0.00 38.18 33.96 0.78 0.37 37.81 33.96 0.78 1.47 36.71 33.96 0.78 3.28 34.90 33.96 0.78 5.81 32.37 10 33.96 0.78 9.05 29.13 http://www.nuoc.com.vn ... MODERNWATERDISTRIBUTIONSYSTEMS 1.3.1 The Overall Systems Water utilities construct, operate, and maintain water supply systems The basic function of these water utilities is to obtain water from... Aspects of Water Distribution 1.3 1.2.1 Ancient Urban Water Supplies 1.3 1.2.2 Status of Water Distribution Systems in the 19th Century 1.9 1.3 1.2.3 Perspectives on Water Distribution. .. Data Water distribution systems handbook/ Larry W Mays, ed p cm Includes bibliographical references ISBN 0-07-134213-3 Water? ??Distributions Hanbooks, manuals, etc Water? ??supply engineering Handbooks,