Urban Stormwater Hydrology
WATER RESOURCES MONOGRAPH SERIES
Water Resources Monograph Series Volume 1 Synthetic Streamflows M.B Fiering and B.B. Jackson Volume 2 Benefit-Cost Analysis for Water System Planning C.W. Howe Volume 3 Outdoor Recreation and Water Resources Planning J.L. Knetsch Volume 4 Multiobjective Water Resource Planning D.C. Major Volume 5 Groundwater Management: The Use of Numerical Models Y. Bachmat, J. Bredehoeft, B. Andrews, D. Holtz, and S. Sebastian Volume 6 Metropolitan Water Management J. Gordon Milliken and Graham C. Taylor
WATERESOURCES MONOGRAPH 7 Urban Stormwater Hydro!ogy David F. Kibler, Editor AMERICAN GEOPHYSICAL WASHINGTON, D.C. 1982 UNION
Published under the aegis of the American Geophysical Union' s Water Resources Monograph Board; John D. Bredehoeft, Chairman; David Dawdy; Charles W. Howe; Thomas Maddock, III; Helen J. Peters; Eric Wood Water Resources Monograph Series Urban Stormwater Hydrology David F. Kibler, editor Copyright 1982 by the American Geophysical Union 2000 Florida Avenue, N.W. Washington, D.C. 20009 Library of Congress Cataloging in Publication Data Main entry under title: Urban stormwater hydrology. (Water resources monograph ; 7) Includes bibliographies. 1. Urban hydrology--addresses, essays, lectures. 2. Storm sewers--addresses, essays, lectures. I. Kibler, D. F. (David F.), 1940-. II. American Geophysical Union. Urban Hydrology Committee. III. Series. TC409. U7 628 '. 212 81-12757 ISBN 0-87590-308-0 AACR2 10987 65432 Printed in the United States of America
PREFACE This monograph has been written over the last 2 years by eight members of the AGU Urban Hydrology Committee as a means of conveying state-of-the-art practices in the expanding field of urban hydrology and stormwater management. Although numerous references to on-going research are cited, the monograph is intended to serve primarily as a practical guide to methods and models currently in use to analyze different types of stormwater management problems. With this objective in mind, the authors have made a special effort to include examples which help illustrate the steps in a particular procedure or analysis. The monograph presumes a basic background in hydrology and makes no real effort to present conventional procedures which can be found readily in available hydrology textbooks. However, the detailed example calculations in Chapters 2, 3, and 4 should assist the unfamiliar reader in understanding basic hydrologic computations related to urban rainfall-runoff analysis. Given this coverage, the monograph should be useful as a reference to practicing engineers and urban planners as well as to graduate students in engineering-environmental disciplines with career interests in the growing field of urban hydrology and stormwater management. On behalf of the individual chapter authors and the AGU Urban Hydrology Committee, I wish to express a note of appreciation to those who have served in a review capacity and helped to bring this monograph to fruition. In this regard, a special note of thanks goes to Ben Urbonas of the Denver Urban Drainage and Flood Control District, David Lystrom and Ernest Cobb of the U.S. Geological Survey, and David Dawdy of Northern Technical Services, Inc. David F. Kibler, Monograph Editor vii
CONTENTS Preface vii 1. INTRODUCTION TO URBAN HYDROLOGY AND STORMWATER MANAGEMENT Jacques W. Delleur Overview of monograph... 1 Urban hydrology and the stormwater problem... 4 Historical perspective of urban hydrology... 8 Interaction of land use and urban stormwater runoff... 9 Stormwater planning in the urban metroplex... 19 New directions in urban hydrology and stormwater management. 26 2. RAINFALL FOR URBAN STORMWATER DESIGN Harry G. Wenzel, Jr. Introduction... 35 Rainfall data... 36 Depth-duration-frequency analysis... 39 Areal effect on point rainfall... 47 Design rainfall duration... 47 Time distribution of design rainfall... 48 Examples of design rainfall development... 55 Advantages and disadvantages of design rainfalls... 60 Current design rainfall research... 61 Alternatives to design rainfall approach... 62 Design rainfall for detention storage... 63 Rainfall for water quality studies... 64 3. RAINFALL ABSTRACTIONS Gert Aron Introduction... 69 Interception... 69 Depression storage... 70 Infiltration... 72 SCS method... 79 The index... 82 Importance of losses in urbanized basins- Effective runoff areas... 84
4. DESK-TOP METHODS FOR URBAN STORMWATER CALCULATION David F. Kibler Role of desk-top methods in urban stormwater analysis... 87 Calder Alley drainage system... 88 Rational method for storm drain design... 90 Soil Conservation Service composite hydrograph method for small urban drainage systems (TR 55)... 99 Time of concentration in the urban basin... 107 Synthetic unit hydrograph methods for urban watersheds... 113 Summary of desk-top model results... 125 Desk-top methods for urban runoff quality... 127 5. URBAN RUNOFF PROCESSES Larry R. Roesner Introduction... 137 The surface runoff subsystem... 144 The transport subsystem... 152 6. QUALITY OF URBAN RUNOFF Larry A. Roesner Background... 161 Pollution potential o stormwater... 162 Sources of pollutants... 165 Entry of pollutants into urban runoff... 168 Estimation of the rate of pollutant buildup on urban watersheds... 175 Washoff of pollutants... 178 Washoff from undeveloped land areas... 179 Washoff rates for pollutants other than solids... 181 Role of the transport system... [82 Environmental assessment considerations... 184 7. DATA COLLECTION AND INSTRUMENTATION Marshall E. Jennings Data collection strategy... 189 Types of data and examples... 191 Rainfall and other meterological data... 191 Streamflow data... 193 Chemical and biological data... 194 Land use characteristics... 198 Examples of instrumentation in urban stormwater investigations 202 Water quality sampling subsystem... 211 Examples of data collection strategy... 212
8. OVERVIEW OF URBAN STORMWATER MODELS Sterios A. Dendrou Introduction... 219 Role of urban stormwater models and levels of analysis... 220 Planning models... 221 Design and analysis models... 226 Operation and control models... 233 Other models... 235 Comparative stud ies... 240 Data requirements... 241 Model calibration, va{idation, and verificagion... 242 9. EXAMPLE MODEL APPLICATIONS Harry C. Torno Introduction... 249 Four Mile Run' Planning and analysis... 251 Bucyrus, Ohio' Analysis and design... 254 Edmonton, Alberta' Analysis and design... 255 Bloomington-Normal, Illinois' Planning and analysis... 259 Borough of East York (Toronto, Ontario)' Analysis... 262 Dorchester Bay' Planning and analysis... 263 Other applications... 266 Conclusion... 268