DOCSLIB.ORG

Hydro-Mechanical Analysis of Breach Processes Due to Levee Failure

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Hydro-Mechanical Analysis of Breach Processes Due to Levee Failure UNIVERSITÉ D’AIX-MARSEILLE ÉCOLE DOCTORALE SCIENCE POUR L’INGÉNIEUR: MÉCANIQUE, PHYSIQUE, MICRO ET NANOÉLECTRONIQUE THÈSE HYDRO-MECHANICAL ANALYSIS OF BREACH PROCESSES DUE TO LEVEE FAILURE PRÉPARÉE À IRSTEA D’AIX-EN-PROVENCE POUR OBTENIR LE GRADE DE DOCTEUR DE L’UNIVERSITÉ D’AIX-MARSEILLE SPÉCIALITÉ MÉCANIQUE DES SOLIDES PAR LIU ZHENZHEN SOUTENUE PUBLIQUEMENT LE 03 JUILLET 2015 DEVANT LE JURY COMPOSÉ DE Frédéric Golay Rapporteur MCF, Université du Sud Toulon Var Didier Marot Rapporteur PR, IUT de Saint-Nazaire Fabien Anselmet Examinateur PR, Ecole Centrale de Marseille Said EI Youssoufi Examinateur PR, Université de Montpellier Stéphane Bonelli Directeur de thèse DR, IRSTEA, Aix en Provence Introduction Floods can have serious consequence in floodplains. Worldwide, many areas can become flooded or are at risk, and numerous people risk being displaced. Determining flood risks is an effective method of ensuring safety against inundation. The accurate analysis of the failure of flood protection structures is the first step in mapping the resulting inundation in a floodplain. Thus, hydro-mechanical analyses of breach processes due to the failure of embankment dams and levees are conducted. As one of the main cause of the serious failure of embankment dams and levees, piping (or the internal erosion of soil) failure process is simulated in Chapter 2. The pipe flow with erosion mechanism is employed into the pipe enlargement model for embankment dams and levees. The hydraulic head variation in the upstream, the trail water conditions in the downstream, the collapse of the pipe top and the transition to a breach are taken into account in the pipe enlargement model. Once a breach is formed, it begins to enlarge downward and laterally. The hydraulic erosion in the breach and episodic retreat of the headcut are considered as controlling mechanisms during breach widening processes. A simply headcut migration model based on the soil tensile strength is presented in Chapter 3 to simulate the critical length of the headcut. Input parameters of this model are: the breach geometry, the soil properties and the flow situations in the breach. Heights of embankment dams ranging from 2 to 12 meters are used to calculate the critical lengths of the headcut under different soil tensile strengths ranging from 0 to 18 kPa. This analytical model is verified by the traditional side slope stability analysis method with three typical embankment dam scales (2, 4 and 6 meters high) in Chapter 4. Due to quick variations of flow streamlines in the breach, distributions of shear stress on the boundary of the breach are complex with the effects of the secondary flow. To accurate estimate erosion processes, a simple numerical model is proposed to calculate averaged lateral and bottom shear stresses and the depth-averaged velocity in Chapter 5. It accounts I for turbulent effects via the dimensionless eddy viscosity coefficient , and secondary flow effects via the dimensionless secondary flow parameters k1 and k2 . A large-scale test is used to validate our numerical model in Chapter 6. The comparisons with measured data are with good agreements. II Contents Chapter 1. Bibliography 1.1. Floods and flood risk ................................................................................................ 3 1.1.1. Floods in China .................................................................................................... 3 1.1.2. Floods in France ................................................................................................. 12 1.2. Breach models of embankment dam and levee failures ...................................... 15 1.2.1. Introduce............................................................................................................. 15 1.2.2. Experimental breach models .............................................................................. 16 1.2.3. Physical breach models ...................................................................................... 20 1.3. Laboratory and field dam breach tests ................................................................. 35 1.3.1. IMPACT project in the EU (from 2001 to 2004) ............................................... 35 1.3.2. Overtopping research in the US ......................................................................... 37 1.3.3. Headcut migration tests ...................................................................................... 42 1.4. Conclusions .............................................................................................................. 46 Chapter 2. Pipe enlargement processes 2.1. Literature review of the failure of embankment dams and levees due to internal erosion and piping .......................................................................................................... 49 2.1.1. Introduction ........................................................................................................ 49 2.1.2. Initiation and continuation of erosion ................................................................ 49 2.1.3. Pipe enlargement ................................................................................................ 50 2.1.4. Formation of breach ........................................................................................... 54 2.1.5. Breach widening ................................................................................................. 55 2.2. Piping flow with erosion ......................................................................................... 55 2.2.1. General introduction of pipe flow ...................................................................... 55 2.2.2. Soil surface erosion by tangential flow .............................................................. 56 2.2.3. Pipe flow with erosion ....................................................................................... 57 I 2.3. Soil erodibility ......................................................................................................... 58 2.3.1. Soil erodibility tests ........................................................................................... 58 2.3.2. Erosion rate coefficient ...................................................................................... 60 2.3.3. Critical shear stress ............................................................................................ 62 2.4. Model for pipe enlargement ................................................................................... 63 2.4.1. Model description .............................................................................................. 63 2.4.2. Model calculation ............................................................................................... 66 2.4.3. Computational algorithm ................................................................................... 69 2.5. Conclusions.............................................................................................................. 69 Chapter 3. Breach widening processes 3.1. Literature review of the breach widening processes ........................................... 73 3.1.1. The formation of a breach .................................................................................. 73 3.1.2. Breach enlargement ........................................................................................... 73 3.1.3. Final breach ........................................................................................................ 80 3.2. The breach width expression ................................................................................. 82 3.2.1. Simplifications of breach geometry ................................................................... 82 3.2.2. Calculation of the breach width ........................................................................ 84 3.2.3. General classification of breach widening ......................................................... 84 3.2.4. The knowledge of the two variables .................................................................. 85 3.3. Headcut migration .................................................................................................. 87 3.3.1. Failure modes ..................................................................................................... 87 3.3.2. Sketch of a headcut ............................................................................................ 89 3.3.3. Failure criterions ................................................................................................ 90 3.3.4. Soil shear strength .............................................................................................. 90 3.3.5. Bending failure calculations .............................................................................. 94 3.3.6. Shear failure calculations ................................................................................. 103 3.4. Analytical results and discussion......................................................................... 109 3.4.1. The specific soil weight ................................................................................... 110 3.4.2. The water head in the breach ........................................................................... 110 3.4.3. The ratio of the depth of erosion to the water head ......................................... 110 3.4.4. Infiltration coefficient ...................................................................................... 111
Load more

Recommended publications
  • Enhancing the Resilience to Flooding Induced by Levee Breaches In
    Nat. Hazards Earth Syst. Sci., 20, 59–72, 2020 https://doi.org/10.5194/nhess-20-59-2020 © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Enhancing the resilience to flooding induced by levee breaches in lowland areas: a methodology based on numerical modelling Alessia Ferrari, Susanna Dazzi, Renato Vacondio, and Paolo Mignosa Department of Engineering and Architecture, University of Parma, Parco Area delle Scienze 181/A, 43124 Parma, Italy Correspondence: Alessia Ferrari ([email protected]) Received: 18 April 2019 – Discussion started: 22 May 2019 Revised: 9 October 2019 – Accepted: 4 December 2019 – Published: 13 January 2020 Abstract. With the aim of improving resilience to flooding occurrence of extreme flood events (Alfieri et al., 2015) and and increasing preparedness to face levee-breach-induced in- the related damage (Dottori et al., 2018) in the future. undations, this paper presents a methodology for creating a Among the possible causes of flooding, levee breaching wide database of numerically simulated flooding scenarios deserves special attention. Due to the well-known “levee ef- due to embankment failures, applicable to any lowland area fect”, structural flood protection systems, such as levees, de- protected by river levees. The analysis of the detailed spa- termine an increase in flood exposure. In fact, the presence tial and temporal flood data obtained from these hypothetical of this hydraulic defence creates a feeling of safety among scenarios is expected to contribute both to the development people living in flood-prone areas, resulting in the growth of of civil protection planning and to immediate actions during settlements and in the reduction of preparedness and hence a possible future flood event (comparable to one of the avail- in the increase in vulnerability in those areas (Di Baldassarre able simulations in the database) for which real-time mod- et al., 2015).
    [Show full text]
  • Preliminary Report on the Performance of the New Orleans Levee Systems in Hurricane Katrina on August 29, 2005
    Preliminary Report on the Performance of the New Orleans Levee Systems in Hurricane Katrina on August 29, 2005 by R.B. Seed, P.G. Nicholson, R.A. Dalrymple, J. Battjes, R.G. Bea, G. Boutwell, J.D. Bray, B. D. Collins, L.F. Harder, J.R. Headland, M. Inamine, R.E. Kayen, R. Kuhr, J. M. Pestana, R. Sanders, F. Silva-Tulla, R. Storesund, S. Tanaka, J. Wartman, T. F. Wolff, L. Wooten and T. Zimmie Preliminary findings from field investigations and associated studies performed by teams from the University of California at Berkeley and the American Society of Civil Engineers, as well as a number of cooperating engineers and scientists, shortly after the hurricane. Report No. UCB/CITRIS – 05/01 November 2, 2005 New Orleans Levee Systems Hurricane Katrina August 29, 2005 This project was supported, in part, by the National Science Foundation under Grant No. CMS-0413327. Any opinions, findings, and conclusions or recommendations expressed in this report are those of the author(s) and do not necessarily reflect the views of the Foundation. This report contains the observations and findings of a joint investigation between independent teams of professional engineers with a wide array of expertise. The materials contained herein are the observations and professional opinions of these individuals, and does not necessarily reflect the opinions or endorsement of ASCE or any other group or agency, Table of Contents i November 2, 2005 New Orleans Levee Systems Hurricane Katrina August 29, 2005 Table of Contents Executive Summary ...……………………………………………………………… iv Chapter 1: Introduction and Overview 1.1 Introduction ………………………………………………………………... 1-1 1.2 Hurricane Katrina ………………………………………………………….
    [Show full text]
  • A FAILURE of INITIATIVE Final Report of the Select Bipartisan Committee to Investigate the Preparation for and Response to Hurricane Katrina
    A FAILURE OF INITIATIVE Final Report of the Select Bipartisan Committee to Investigate the Preparation for and Response to Hurricane Katrina U.S. House of Representatives 4 A FAILURE OF INITIATIVE A FAILURE OF INITIATIVE Final Report of the Select Bipartisan Committee to Investigate the Preparation for and Response to Hurricane Katrina Union Calendar No. 00 109th Congress Report 2nd Session 000-000 A FAILURE OF INITIATIVE Final Report of the Select Bipartisan Committee to Investigate the Preparation for and Response to Hurricane Katrina Report by the Select Bipartisan Committee to Investigate the Preparation for and Response to Hurricane Katrina Available via the World Wide Web: http://www.gpoacess.gov/congress/index.html February 15, 2006. — Committed to the Committee of the Whole House on the State of the Union and ordered to be printed U. S. GOVERNMEN T PRINTING OFFICE Keeping America Informed I www.gpo.gov WASHINGTON 2 0 0 6 23950 PDF For sale by the Superintendent of Documents, U.S. Government Printing Office Internet: bookstore.gpo.gov Phone: toll free (866) 512-1800; DC area (202) 512-1800 Fax: (202) 512-2250 Mail: Stop SSOP, Washington, DC 20402-0001 COVER PHOTO: FEMA, BACKGROUND PHOTO: NASA SELECT BIPARTISAN COMMITTEE TO INVESTIGATE THE PREPARATION FOR AND RESPONSE TO HURRICANE KATRINA TOM DAVIS, (VA) Chairman HAROLD ROGERS (KY) CHRISTOPHER SHAYS (CT) HENRY BONILLA (TX) STEVE BUYER (IN) SUE MYRICK (NC) MAC THORNBERRY (TX) KAY GRANGER (TX) CHARLES W. “CHIP” PICKERING (MS) BILL SHUSTER (PA) JEFF MILLER (FL) Members who participated at the invitation of the Select Committee CHARLIE MELANCON (LA) GENE TAYLOR (MS) WILLIAM J.
    [Show full text]
  • Cost-Effective Levee Design for Cases Along the Meuse River Including Uncertain- Ties in Hydraulic Loads
    Cost-effective levee design for cases along the Meuse river including uncertain- ties in hydraulic loads B. Broers Delft University of Technology . Cost-effective levee design for cases along the Meuse river including uncertainties in hydraulic loads by Ing. B. Broers in partial fulfilment of the requirements for the degree of Master of Science in Civil Engineering at the Delft University of Technology, Faculty of Civil Engineering and Geosciences to be defended publicly on January 15, 2015 Student number: 4184408 Supervisor: Prof. dr. ir. M. Kok, TU Delft - Hydraulic Engineering section Thesis committee: Dr. ir. T. Schweckendiek, TU Delft - Hydraulic Engineering section Ir. drs. J. G. Verlaan, TU Delft - Construction Management and Engineering section Ir. S.A. van Lammeren, Royal HaskoningDHV Ir. drs. E. R. Kuipers, Waterschap Peel en Maasvallei An electronic version of this thesis is available at http://repository.tudelft.nl/. Preface This MSc Thesis reflects the final part of the Master of Science degree in Hydraulic Engineering at the Civil Engineering and Geosciences Faculty of the Delft University of Technology. The research is per- formed under guidance of the Delft University of Technology in cooperation with Royal HaskoningDHV and Waterschap Peel & Maasvallei. I like to thank many people for their support and cooperation during my graduation thesis. In the first place I thank my direct supervisors: Timo Schweckendiek, Enno Kuipers and Bas van Lammeren for their helpful feedback, enthusiasm and guidance during the thesis. Many thanks to Prof. Matthijs Kok for his support and advice. My thanks to Jules Verlaan too, who helped me especially in the field of LCCA.
    [Show full text]
  • When the Levees Break: Relief Cuts and Flood Management in the Sacramento-San Joaquin Delta
    UC Berkeley Hydrology Title When the levees break: Relief cuts and flood management in the Sacramento-San Joaquin Delta Permalink https://escholarship.org/uc/item/4qt8v88d Authors Fransen, Lindsey Ludy, Jessica Matella, Mary Publication Date 2008-05-16 eScholarship.org Powered by the California Digital Library University of California When the levees break: Relief cuts and flood management in the Sacramento-San Joaquin Delta Hydrology for Planners LA 222 Lindsey Fransen, Jessica Ludy, and Mary Matella FINAL DRAFT May 16, 2008 Abstract The Sacramento-San Joaquin Delta is one of California’s most important geographic regions. It supports significant agricultural, urban, and ecological systems and delivers water to two-thirds of the state’s population, but faces extremely high risks of disaster. Largely below sea level and supported by 1,100 miles of aging dikes and levees, the Delta system is subject to frequent flooding. Jurisdictional and financial disincentives to better flood planning prevent coordination that might otherwise reduce both costs and damages. This study highlights one possible flood mitigation technique called a relief cut, which is an intentional break in a downslope levee to allow water that has overtopped or breached an upslope levee to drain back into the river. This flood management technique is “smart” when located in appropriate areas so that floodwaters can be managed most efficiently and safely after a levee break. We identify four key constraints and make four recommendations for flood management planning. The
    [Show full text]
  • The Hurricane Katrina Levee Breach Litigation: Getting the First Geoengineering Liability Case Right
    Richards Final.docx (DO NOT DELETE) 2/10/2012 9:50 AM ESSAY THE HURRICANE KATRINA LEVEE BREACH LITIGATION: GETTING THE FIRST GEOENGINEERING LIABILITY CASE RIGHT † EDWARD P. RICHARDS INTRODUCTION In August 2005, Hurricane Katrina flattened the Gulf Coast from the Alabama border to 100 miles west of New Orleans. The New Or- leans levees failed, and much of the city was flooded. More than 1800 people died,1 and property damage is estimated at $108 billion.2 While Katrina was not the most deadly or expensive hurricane in U.S. history, it was the worst storm in more than eighty years and destroyed public complacency about the government’s ability to respond to disasters. The conventional story of the destruction of New Orleans is that the levees broke because the Army Corps of Engineers (Corps) did not design and build them correctly. The district court’s holding in In re Katrina Canal Breaches Consolidated Litigation (Robinson),3 dis- † Clarence W. Edwards Professor of Law and Director, Program in Law, Science, and Public Health at the Louisiana State University Law Center. Email: rich- [email protected]. For more information, see http://biotech.law.lsu.edu. Thanks to Kathy Haggar and Kelly Haggar of Riparian, Inc., a wetland consulting firm in Baton Rouge, Louisiana, for research assistance in geology and coastal geomorphology. 1 RICHARD D. KNABB ET AL., NAT’L HURRICANE CTR., TROPICAL CYCLONE RE- PORT: HURRICANE KATRINA 11 (2005), available at http://biotech.law.lsu.edu/ katrina/govdocs/TCR-AL122005_Katrina.pdf. 2 Id. at 13. 3 647 F. Supp.
    [Show full text]
  • On the Importance of Analyzing Flood Defense Failures
    7 E3S Web of Conferences, 03013 (2016) DOI: 10.1051/ e3sconf/20160703013 FLOOD risk 2016 - 3rd European Conference on Flood Risk Management On the importance of analyzing flood defense failures 2 1, Myron van Damme1,a, Timo Schweckendiek1,2 and Sebastiaan N. Jonkman1 1Delft University of Technology, Department of Hydraulic Engineering, Delft, Netherlands 2Deltares, Unit Geo-engineering, Delft, Netherlands Abstract. Flood defense failures are rare events but when they do occur lead to significant amounts of damage. The defenses are usually designed for rather low-frequency hydraulic loading and as such typically at least high enough to prevent overflow. When they fail, flood defenses like levees built with modern design codes usually either fail due to wave overtopping or geotechnical failure mechanisms such as instability or internal erosion. Subsequently geotechnical failures could trigger an overflow leading for the breach to grow in size Not only the conditions relevant for these failure mechanisms are highly uncertain, also the model uncertainty in geomechanical, internal erosion models, or breach models are high compared to other structural models. Hence, there is a need for better validation and calibration of models or, in other words, better insight in model uncertainty. As scale effects typically play an important role and full-scale testing is challenging and costly, historic flood defense failures can be used to provide insights into the real failure processes and conditions. The recently initiated SAFElevee project at Delft University of Technology aims to exploit this source of information by performing back analysis of levee failures at different level of detail. Besides detailed process based analyses, the project aims to investigate spatial and temporal patterns in deformation as a function of the hydrodynamic loading using satellite radar interferometry (i.e.
    [Show full text]
  • Levee Breach Consequence Model Validated by Case Study in Joso, Japan
    Levee Breach Consequence Model Validated by Case Study in Joso, Japan Paul Risher, PE, Hydraulic Engineer, Risk Management Center (RMC), US Army Corps of Engineers (USACE); Cameron Ackerman, PE, D.WRE, Senior Hydraulic Engineer, Hydrologic Engineering Center (HEC), USACE; Jesse Morrill-Winter, Regional Economist, Sacramento District, USACE; Woodrow Fields, Hydraulic Engineer, HEC, USACE; and Jason T. Needham, PE, Senior Consequence Specialist, RMC, USACE Abstract-- In September 2015, extreme rainfall from two tropical cyclones caused the Kinugawa River levee to overtop and breach in three locations near the city of Joso, Japan. Citizens, government agencies, and television news observed the breaches and resultant flood damages. The well-documented disaster provides a unique opportunity to validate levee breach progression, flooding, evacuation, and lifeloss estimations generated by the suite of models used by USACE and others to support levee safety risk assessments. In this paper, we describe how data from social media augmented official sources to create a complete and accurate data set. Specifically, we scoured multiple online sources to describe the breach erosion progression at a level of detail rarely available outside of a controlled environment. We then describe the multi-step modeling process of: 1) setting up the HEC-RAS river hydraulics model, with the required boundary conditions and breach parameters; 2) calibrating the HEC-RAS model to observed breach flow velocities, flood depths, and inundation extents in the leveed area; and 3) using the HEC-RAS results and the available information on warnings and evacuation to validate the estimates of life loss from HEC-LifeSim. I. INTRODUCTION Flood risk for a given flood defense structure is a combination of the probability of failure of the structure and the consequences of that failure.
    [Show full text]
  • Rotterdam University of Applied Sciences Muh Aris Marfai, Gadjah Mada University, Yogyakarta
    Connecting Delta Cities COASTAL CITIES, FLOOD RISK MANAGEMENT AND ADAPTATION TO CLIMATE CHANGE Connecting Delta Cities Jeroen Aerts, VU University Amsterdam David C. Major, Columbia University Malcolm J. Bowman, State University of New York, Stony Brook Piet Dircke, Rotterdam University of Applied Sciences Muh Aris Marfai, Gadjah Mada University, Yogyakarta COASTAL CITIES, FLOOD RISK MANAGEMENT AND ADAPTATION TO CLIMATE CHANGE Authors Acknowledgements Jeroen Aerts, David C. Major, Malcolm J. Bowman, We gratefully acknowledge the generous support and Piet Dircke, Muh Aris Marfai participation of Adam Freed (City of New York), Aisa Tobing (Jakarta Governor’s Office), Raymund Kemur Contributing authors (Ministry of Spatial Planning, Indonesia) and Arnoud Abidin, H.Z., Ward, P., Botzen, W., Bannink, B.A., Molenaar (City of Rotterdam). We thank the City of Lon- Nickson, A., Reeder, T. don, Alex Nickson, Tim Reeder of the UK Environment Agency, Robert Muir-Wood and Hans Peter Plag for their Sponsors participation and support. We furthermore thank Florrie This book is sponsored by the City of Rotterdam, de Pater of the Knowledge for Climate program for her and Rotterdam Climate Proof and the Dutch research support on communication aspects, Mr Scott Sullivan program for Climate (KvK). The Connecting Delta Cities and his staff of Stony Brook University for providing faci- network has been addressed as a joint action under lities and assistance at the Manhattan campus, Cynthia the Clinton C40 initiative. For more information on Rosenzweig and colleagues at Columbia and NASA GISS these initiatives and their relation to Connecting for information and participation, Klaus Jacobs of Colum- Delta Cities, please see: bia University, William Solecki of Hunter College and Colophon www.deltacities.com.
    [Show full text]
  • Hurricane Katrina External Review Panel Christine F
    THE NEW ORLEANS HURRICANE PROTECTION SYSTEM: What Went Wrong and Why A Report by the American Society of Civil Engineers Hurricane Katrina External Review Panel Christine F. Andersen, P.E., M.ASCE Jurjen A. Battjes, Ph.D. David E. Daniel, Ph.D., P.E., M.ASCE (Chair) Billy Edge, Ph.D., P.E., F.ASCE William Espey, Jr., Ph.D., P.E., M.ASCE, D.WRE Robert B. Gilbert , Ph.D., P.E., M.ASCE Thomas L. Jackson, P.E., F.ASCE, D.WRE David Kennedy, P.E., F.ASCE Dennis S. Mileti, Ph.D. James K. Mitchell, Sc.D., P.E., Hon.M.ASCE Peter Nicholson, Ph.D., P.E., F.ASCE Clifford A. Pugh, P.E., M.ASCE George Tamaro, Jr., P.E., Hon.M.ASCE Robert Traver, Ph.D., P.E., M.ASCE, D.WRE ASCE Staff: Joan Buhrman Charles V. Dinges IV, Aff.M.ASCE John E. Durrant, P.E., M.ASCE Jane Howell Lawrence H. Roth, P.E., G.E., F.ASCE Library of Congress Cataloging-in-Publication Data The New Orleans hurricane protection system : what went wrong and why : a report / by the American Society of Civil Engineers Hurricane Katrina External Review Panel. p. cm. ISBN-13: 978-0-7844-0893-3 ISBN-10: 0-7844-0893-9 1. Hurricane Katrina, 2005. 2. Building, Stormproof. 3. Hurricane protection. I. American Society of Civil Engineers. Hurricane Katrina External Review Panel. TH1096.N49 2007 627’.40976335--dc22 2006031634 Published by American Society of Civil Engineers 1801 Alexander Bell Drive Reston, Virginia 20191 www.pubs.asce.org Any statements expressed in these materials are those of the individual authors and do not necessarily represent the views of ASCE, which takes no responsibility for any statement made herein.
    [Show full text]
  • New Techniques for the Rapid Repair of Levee Breaches
    Flood Recovery, Innovation and Response II 85 New techniques for the rapid repair of levee breaches S. J. Boc, D. T. Resio & E. C. Burg US Army Corps of Engineers, Engineer Research and Development Center, Coastal and Hydraulics Laboratory, USA Abstract Levee breaching is a widespread issue that has had few technological improvements in history. Recent severe flooding situations have created a critical need for a rapid levee repair capability that can function in a wide range of different environments. For levee repair capabilities to make a substantial difference in interior flood levels and damages, they must act very quickly and minimize the chance of additional “unraveling” along the levee. A successful technology must be capable of functioning in extremely austere situations with little conventional logistics support and little or no site preparation. One alternative is to use the one resource readily available during floods; water, as the main structural element in conjunction with high-strength fabrics. The incompressibility of water in a closed high-strength fabric tube can create a stable geometric configuration capable of resisting deformation through a breach. In September 2008 three concepts for levee repair and protection were tested and demonstrated in a 1:4 scale physical model at the Hydraulic Engineering Research Unit, Agricultural Research Service in Stillwater, Oklahoma. Test results will be discussed. Keywords: levee breach, high strength fabric, levee breach repair. 1 Introduction Hurricane Katrina was a prime example showing how coastal and inland areas are vulnerable to natural and/or man-made disasters related to levee/floodwall breaching. This situation has created awareness for the need of a rapid levee repair capability that is adaptable to a wide range of environments (US Gulf WIT Transactions on Ecology and the Environment, Vol 133, © 2010 WIT Press www.witpress.com, ISSN 1743-3541 (on-line) doi:10.2495/FRIAR100081 86 Flood Recovery, Innovation and Response II Coast, Lake Okeechobee, Sacramento River, etc.).
    [Show full text]
  • Modeling Residual Flood Risk Behind Levees, Upper Mississippi River, USA
    Contents lists available at ScienceDirect Environmental Science & Policy journal homepage: www.elsevier.com/locate/envsci Modeling residual flood risk behind levees, Upper Mississippi River, USA Nicholas Pintera,*, Fredrik Huthoffb, Jennifer Dierauerc, Jonathan W.F. Remod, Amanda Damptzc a Dept. of Earth and Planetary Sciences, University of California, Davis CA 93616, USA b HKV Consultants, Botter 11-29, Lelystad, The Netherlands c Department of Geology, Southern Illinois University, Carbondale, IL 62901, USA d Dept. of Geography and Environmental Resources, Southern Illinois University, Carbondale, IL 62901, USA ARTICLE INFO ABSTRACT Article history: Flood protection from levees is a mixed blessing, excluding water from the floodplain but creating higher Received 16 February 2015 flood levels (“surcharges”) and promoting “residual risk” of flood damages. This study completed 2D Received in revised form 8 January 2016 hydrodynamic modeling and flood-damage analyses for the 4592 km Sny Island levee system on the Accepted 8 January 2016 Upper Mississippi River. These levees provide large economic benefits, at least $51.1 million per year in prevented damages, the large majority provided to the agricultural sector and a small subset of low- Keywords: elevation properties. However these benefits simultaneously translate into a large residual risk offlood Flooding damage should levees fail or be overtopped; this risk is not recognized either locally in the study area nor Floodplain management in national policy. In addition, the studied levees caused surcharges averaging 1.2–1.5 m and locally as Social vulnerability Hydraulic modeling high as 2.4 m, consistent with other sites and studies. The combined hydraulic and economic modeling Mississippi River here documented that levee-related surcharge + the residual risk of levee overtopping or failure can lead to negative benefits, meaning added long-term flood risk.
    [Show full text]