What We Have Learned Since the Big Thompson Flood Proceedings of the Tenth Anniversary Conference July I7-1 9. 1986 Boulder, Colorado What We Have Learned Since the Big Thompson Flood Eve C. Gruntfest Editor Proceedings of the Tenth Anniversary Conference July 17-1 9. 1986 Boulder. Colorado Natural Hazards Research and Applications Information Center Special Publication #16 1987 The opinions and recommendations contained herein are those of the authors and conference participants, and do not necessarily reflect those of the funding or sponsoring agencies or organizations. Cover photo: Scene in the Big Thompson Cahyon, Colorado, on August 1, 1976. Available from: The Natural Hazards Research and Applications Information Center Institute of Behavioral Science University of Colorado Campus Box 482 Boulder, CO 80309 I NTRODUCTI UN The Symposium held in Boulder on July 17-19, 1986, offered a rare opportunity to look back and assess the strengthS and weaknesses of post­ disaster research and policy initiatives. The meeting drew together participants from a wide range of disciplines to analyze the premise that disasters are opportunities for change, and to set the flash flood research and policy agenda for the remainder of the century. Part One provides an overview of the Big Thompson flood in light of recent experiences. Gruntfest's "Common Ground" describes the flood and appraises the progress in flash flood hazard mitigation in the Big Thompson Canyon, the state of Colorado, and the United States as a whole. In his paper, Wright, the governor's representative to the recovery effort, reflects on the state's role. Kistner presents an overview of the 1982 Estes Park dam-break flood, analyzing how the 1982 recovery process was influenced by lessons learned after the 1976 Big Thompson experience. Charney, forensic anthropologist in charge of body identification after the Big Thompson flood, discusses the operation of a temporary morgue following a disaster, a frequently ignored aspect of emergency preparedness. Part Two is comprised of ten papers that address mitigation issues, as they arise at various levels of government. At the federal level, Steinberg presents the Corps of Engineers' flood damage reduction program, and Olson and Gore discuss direction in the National Flood Insurance Program since 1976. Truby, Stanton, and Wright examine state mitigation efforts: Truby focuses on dam failure hazards; Stanton concentrates on the Colorado Flood Hazard Mitigation Plan; and Wright provides a legislator's perspective in appraisal of mitigation efforts over the last decade. Regional and local impacts are considered in papers by DeGroot and Tucker and Havlick. DeGroot and Tucker's paper identifies the nationally recognized efforts of the Urban Drainage and Flood Control District in the Denver metropolitan area. As a member of the Boulder City Council, Havlick looks at the impacts the Big Thompson flood has had in Boulder, 35 miles away from the Big Thompson Canyon. The mitigation section is rounded out by Platt's paper on the post-disaster mitigation teams begun by FEMA in 1979, and by Dye's discussion of the private sector's role in selling flood insurance. Part Three covers forecasting innovations. The paper by Belville and Wagoner provides an overview of changes in National Weather Service policies and programs since 1976. Johnson's paper, the Tucker and Reiter contribution, and Scofield's paper deal primarily with innovations in forecasting models of hydrologic systems and precipitation. The section concludes with a paper by VanBlargen identifying the technological advancements in flash flood forecasting within the National Weather Service in the past decade. Part Four concentrates on warning and response. Graham's paper details the warning experience preceding the 1982 Estes Park dam break. Boulder's sophisticated automated flash flood warning system is described by Van Wie. Sorensen examines the 1985 Cheyenne flood warning system and compares the situation to the Big Thompson. Minnesota's innovative network for disaster stress intervention is described by Huber. Handmer and Penning-Rowsell 's paper discusses Australian experiences with flood warnings. Hostetter wraps up the section with his paper on Mennonite studies of social impacts of disasters. Part Five contains papers on geomorphology and hydrology. Jarrett documents hydrologic research relevant to the 1976 flood, and Hoyt's paper compares the Big Thompson impacts with those of the 1982 Estes Park dam-break flood Part Six includes a summary of the recommendations made by participants in the Symposium. The Symposium participant list is included as Appendix I. Appendix II has background papers for additional information on the actions people took during the flood, and on the land acquisition program implemented following the flood. Abstracts of papers not included in the Proceedings but presented at the Symposium are in Appendix III. An extensive bibliography of articles and books written on the Big Thompson flood serves as Appendix IV. ACKNOWLEDGEMENTS Presentations made during the Symposium form the basis for these Proceedings. am grateful to all who took the time to make their contributions. The names of all the Symposium participants are provided in Appendix I. J. Eleonora Sabadell of the National Science Foundation, and Dennis Walts of the National Oceanic and Atmospheric Administration Environmental Research Laboratories provided financial support for the Symposium. William Donovan of the United States Army Corps of Engineers funded the publication of the Proceedings volume by the Natural Hazards Research and Applications Information Center. William Anderson of the National Science Foundation, and James Null, Dean of the College of Letters, Arts and Sciences, University of Colorado, Colorado Springs, provided initial encouragement and support for the project. Technical support and early encouragement were provided by an advisory committee that included Curtis Barrett, National Oceanic and Atmospheric Administration; William Gordon, Larimer County Office of Emergency Management; Brian Hyde, Colorado Water Conservation Board; Jon Kusler, J.A. Kusler and Associates; Dale Lillie, National Weather Service, Kansas City; Thomas McKee and Dennis Mileti, Colorado State university; Maurice Pautz, National Weather Service Denver Forecasting Office; Rutherford Platt, University of Massachusetts; John Swanson, Federal Emergency Management Agency; Jack Truby, Colorado Department of Disaster Emergency Services; Susan Tubbesiny, Natural Hazards Research and Applications Information Center; and Dennis Walts, National Oceanic and Atmospheric Administration, Environmental Research Laboratories. The success of the Symposium depended upon many individuals and sponsoring organizations. Jon Kusler, Rutherford Platt, and John Handmer, of the Australian National University, were at a meeting in Great Britain where the inspiration for the Symposium first came. The staff of the Natural Hazards Research and Applications Information Center, in particular Susan Tubbesing and Sarah Nathe, deserve special mention for their advice from the time the Symposium idea first hatched in 1984, to the publication of the Proceedings in 1987. Staff of the Disaster Assistance Program at FEMA/Region VIII in Denver were especially helpful in starting to implement the plans. Post-Symposium comments from Howard Gaskill, New Hampshire Civil Defense; Lawrence Kollenbrander, Western Carolina University; H. James Owen, Flood Loss Reduction Associates; Bory Steinberg, U.S. Army Corps of Engineers; Gilbert White, University of Colorado; and James Wright, Tennessee Valley Authority, help pave the way for application of the recommendations. Special thanks are due to Gilbert White for his excellent closing remarks and for his continuing inspiration. The support team for the Symposium was superb. Carole Huber applied her keen brain and strong organizational abilities before, during, and after the Symposium and kept us all on schedule. Mary McCutchen, Skye Ridley, Donna Huntington, Joni Stephens, and Lucy Brooke of the Federal Emergency Management Agency, and Kate Ord assisted with the registration and field trip details. Eve C. Gruntfest Conference Organizer University of Colorado at Colorado Springs TABLE OF CONTENTS Introduction •• iii Acknowledgements v PART ONE: THE FLOOD IN CONTEXT Common Ground Eve C. Gruntfest 3 State Response to the Big Thompson Canyon Disaster Kenneth R. Wright ••••••••••••• 9 Flash Flood Preparedness of Public Entities in Colorado Brian Hyde. • •• • ••••••••••••••• 17 Building on a Disaster Robert L. Kistner. 19 The Temporary Morgue Operation Mi chael Charney ••••• 22 PART TWO: MITIGATION MEASURES Policy Changes Affecting the Corps of Engineers Flood Damage Prevention Program Bory Steinberg•••••••• 27 The Big Thompson Disaster--Then and Now Jerome M. Olson •••• 35 The National Flood Insurance Program 1976-1986 Douglas Gore ••••••••••••••• 41 The Dam Failure Hazard: Awareness and Preparedness in Colorado Jack Truby •••••••••••••• 50 Changes In Our Understanding of Mitigation William P. Stanton •• 52 Changes at the State Level Since 1976 Ruth M. Wright. 57 Successful Flood Management on a Regional Basis William G. DeGroot and L. Scott Tucker. 68 How the Big Thompson Flood has Affected Local Flood Prevention Efforts Spenser W. Havlick •••. 75 Post-Flood Hazard Mitigation: A Legacy of Big Thompson Rutherford H. Platt •••••••• •••• 82 Innovations in the Private Handling of Flood Insurance William M. Dye.