For the engineer, vegetation is a highly variable material hence calculations with vegetation will carry a high degree of uncertainty. The type and condition of vegetation on an embankment can have both positive and adverse effects on embankment performance. Embankments considered within this report comprise sea, river and reservoir flood defences. Why is there vegetation on an embankment? In practice it is important for an embankment to maintain integrity and stability up to (and preferably beyond) the maximum design load conditions. To cope better with these loads, the surface layer is typically protected by different means, including vegetation. As well as the main goal of providing surface protection, the design of embankments may also consider the creation of a more natural river environment and habitats and to promote recreational areas for the surrounding population. In this role, the selection of appropriate vegetation is fundamental. What is the influence of vegetation? Vegetation can have a number of effects beyond the provision of resistance to erosion. Vegetation may affect the conveyance of the river and the performance deterioration processes of embankments. Erosion resistance Vegetation increases the resistance of the embankment surface to erosion because it reduces flow velocity and shear stresses near to the embankment soil surface. Vegetation can also provide direct surface protection to erosion if it is long and flexible enough to lay and cover the soil surface when it is affected by a flow. Further protection from vegetation is provided by the root mat which develops below the bed surface of the embankment providing additional strength to the soil structure. Conveyance Conveyance is a quantitative measure of the discharge capacity of a watercourse. Water levels related to a certain discharge are mainly influenced by the resistance to flow due to surface roughness. In channel vegetation modifies the roughness surface depending on its type (flexibility, size, etc), the season (the expected biomass and the percentage covered will vary during the year), and other factors such as maintenance. Deterioration Vegetation can lead to embankment deterioration in several ways. One of the main types of deterioration relates to changes in soil moisture. In certain soils, prolonged extraction of moisture by plant roots can lead to desiccation and thus to cracking and seepage. Trees on an embankment can also promote local erosion around its trunk causing narrowing of the embankment crosssection. Ultimately, the failure of a tree and its roots could cause severe erosion of the soil. In addition, as vegetation promotes the creation of habitats, it can also encourage burrowing within embankments by vermin. Management actions also affect the performance of vegetation. For example, the eventual strength of the grass is governed by the management regime. Species that are not managed tend to have weak and sparse roots which results in a grass layer far less resistant to erosion.
Integrated Flood Risk Analysis and Management Methodologies Grass Erosion on Embankments AN OVERVIEW Date April 2008 Report Number T04-08-03 Revision Number 9_1 Task Leader HR Wallingford FLOODsite is co-funded by the European Community Sixth Framework Programme for European Research and Technological Development (2002-2006) FLOODsite is an Integrated Project in the Global Change and Eco-systems Sub-Priority Start date March 2004, duration Years Document Dissemination Level PU Public PP Restricted to other programme participants (including the Commission Services) RE Restricted to a group specified by the consortium (including the Commission Services) CO Confidential, only for members of the consortium (including the Commission Services) Co-ordinator: HR Wallingford, UK Project Contract No: GOCE-CT-2004-505420 Project website: www.floodsite.net PU FLOODsite Project Report Contract No:GOCE-CT-2004-505420 DOCUMENT INFORMATION Title Lead Author Contributors Distribution Document Reference Erosion of Embankments - A Review of Current Knowledge Marta Roca Collell, Mark Morris Georg Petersen Public T04-08-03 DOCUMENT HISTORY Date 04/04/08 16/3/09 Revision 1_0 9_1 Prepared by MRC Mark Morris Organisation HRW HRW Approved by Notes Initial drafting Final edits / formatting ACKNOWLEDGEMENT The work described in this publication was supported by the European Community’s Sixth Framework Programme through the grant to the budget of the Integrated Project FLOODsite, Contract GOCE-CT2004-505420 DISCLAIMER This document reflects only the authors’ views and not those of the European Community This work may rely on data from sources external to the FLOODsite project Consortium Members of the Consortium not accept liability for loss or damage suffered by any third party as a result of errors or inaccuracies in such data The information in this document is provided “as is” and no guarantee or warranty is given that the information is fit for any particular purpose The user thereof uses the information at its sole risk and neither the European Community nor any member of the FLOODsite Consortium is liable for any use that may be made of the information © FLOODsite Consortium T04-08-03_ErosionofEmbankments_v9_1.doc ii April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 SUMMARY This report details review work undertaken as part of FLOODsite Task – Understanding and prediction of failure modes, Activity – Front and rear face erosion, Action – Identification of gaps on erosion Erosion of the surface protection of vegetated fluvial and coastal embankments is the first step towards the breaching of an embankment A detailed knowledge of the driving forces, factors and mechanisms is necessary to understand the processes and is a key element in managing failure risks Past and present research on the erosion of surface vegetation has been reviewed and this report provides a brief summary along with listings of relevant projects and research findings Based upon these results, gaps in knowledge were identified and research needs described T04-08-03_ErosionofEmbankments_v9_1.doc iii April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 T04-08-03_ErosionofEmbankments_v9_1.doc iv April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 CONTENTS Document Information ii Document History .ii Acknowledgement ii Disclaimer ii Summary iii Contents v Introduction 1.1 General framework 1.2 Aims and objectives 1.3 Structure of this report 2 Summary of existing knowledge 2.1 Fundamentals about erosion resistance 2.2 Current and Recent knowledge sources 2.2.1 Research Projects 2.2.2 Reference Institutions 2.2.3 Journal Papers Recommended actions and initiatives 3.1 Determination of time to failure 3.2 Vegetation management 3.3 Develop a wider management framework linking vegetation type, management, soil moisture, soil fissuring and soil erodibility 3.4 Improve basic knowledge and understanding of vegetation-erosion processes 3.5 Defining failure modes and mechanisms 3.6 Experimental and field data 3.7 Estimation of vegetation roughness 10 Summary and prioritisation of recommended actions 11 References 13 Appendix 1: Current Research Details 15 Tables Table 2.1 Selected research programmes and projects showing main research topic areas Table 4.1 Summary and prioritisation of recommended actions 11 Figures Figure General framework of vegetated embankments T04-08-03_ErosionofEmbankments_v9_1.doc v April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 T04-08-03_ErosionofEmbankments_v9_1.doc vi April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 1.1 Introduction General framework For the engineer, vegetation is a highly variable material hence calculations with vegetation will carry a high degree of uncertainty The type and condition of vegetation on an embankment can have both positive and adverse effects on embankment performance Embankments considered within this report comprise sea, river and reservoir flood defences Why is there vegetation on an embankment? In practice it is important for an embankment to maintain integrity and stability up to (and preferably beyond) the maximum design load conditions To cope better with these loads, the surface layer is typically protected by different means, including vegetation As well as the main goal of providing surface protection, the design of embankments may also consider the creation of a more natural river environment and habitats and to promote recreational areas for the surrounding population In this role, the selection of appropriate vegetation is fundamental What is the influence of vegetation? Vegetation can have a number of effects beyond the provision of resistance to erosion Vegetation may affect the conveyance of the river and the performance / deterioration processes of embankments Erosion resistance Vegetation increases the resistance of the embankment surface to erosion because it reduces flow velocity and shear stresses near to the embankment soil surface Vegetation can also provide direct surface protection to erosion if it is long and flexible enough to lay and cover the soil surface when it is affected by a flow Further protection from vegetation is provided by the root mat which develops below the bed surface of the embankment providing additional strength to the soil structure Conveyance Conveyance is a quantitative measure of the discharge capacity of a watercourse Water levels related to a certain discharge are mainly influenced by the resistance to flow due to surface roughness In channel vegetation modifies the roughness surface depending on its type (flexibility, size, etc), the season (the expected biomass and the percentage covered will vary during the year), and other factors such as maintenance Deterioration Vegetation can lead to embankment deterioration in several ways One of the main types of deterioration relates to changes in soil moisture In certain soils, prolonged extraction of moisture by plant roots can lead to desiccation and thus to cracking and seepage Trees on an embankment can also promote local erosion around its trunk causing narrowing of the embankment cross-section Ultimately, the failure of a tree and its roots could cause severe erosion of the soil In addition, as vegetation promotes the creation of habitats, it can also encourage burrowing within embankments by vermin Management actions also affect the performance of vegetation For example, the eventual strength of the grass is governed by the management regime Species that are not managed tend to have weak and sparse roots which results in a grass layer far less resistant to erosion Figure summarises the general framework of points highlighting how vegetation influences embankment performance T04-08-03_ErosionofEmbankments_v9_1.doc April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 Motivations • • • • Environmental issues Surface protection Recreational purposes Spontaneously growing Influences on Erosion resistance MANAGEMENT Vegetated embankments Conveyance Deterioration processes Figure 1.2 General framework of vegetated embankments Aims and objectives The objective of this review is to provide a brief overview of knowledge, and hence gaps in knowledge, relating to erosion of embankment surface protection The review does not repeat literature reviews and work already done by others, but instead references these and forms a concise overview of the current state of art, practice and, in particular, identifies where the gaps in knowledge are and what needs to be done to address these 1.3 Structure of this report A summary of fundamental concepts about erosion resistance and existing research projects is presented in Chapter Recommended actions and initiatives are presented in Chapter (taking into account work done) and a suggested prioritisation of these actions is presented in Chapter Supporting material on Current Research Details may be found in Appendix T04-08-03_ErosionofEmbankments_v9_1.doc April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 Summary of existing knowledge This review does not repeat literature reviews and work already done but instead, references these and forms a concise overview of the current state of the art to act as a base to identify where gaps in knowledge exist and how these may be addressed A brief summary of key issues regarding erosion resistance is presented in Section 2.1 An overview of recent and ongoing research projects is given in Section 2.2 In collating the information, outputs from Actions 1-3 of FLOODsite Task are also incorporated, along with past and present research work undertaken in the UK, Germany, the Netherlands, the US and from EC and European national research programmes 2.1 Fundamentals about erosion resistance The surface layer of an embankment needs to cope with a number of different conditions which can occur solely or in combination with each other Loading conditions, for which the intensity may vary include: • Wave breaking impacts on the exposed (seaward / river ward) front face: • Wave run up on the front face • Lateral flow currents along the front face • Overtopping flows over the crest and down the rear (landward) face: • Overflowing - when water levels rise above the crest level and flow passes continuously over the crest • Seepage flows through the embankment (developing into piping) • Rapid drawdown, generating a risk from uplift pressures in the surface cover layers In addition climatic factors have an effect on the embankment condition with, for example, rain and sun leading to wetting and drying of the embankment, combined with frost and ice causing further surface damage Erosion of an embankment occurs when bank material is displaced by the effect of these loads causing friction, drag, lift and pressure forces Erosion can occur on any exposed face, for example the front face, inner toe, crest, rear face and outer toe The initiation and speed of erosion is controlled by the difference between loading forces and resistance forces Whilst the loading forces are dependent on the environmental conditions, the resistance forces are dependent on the embankment design, its shape, type and size of materials used and quality of work The erosion process generally starts when loading forces exceed the resisting forces of particles or elements As a first step, the resistant surface protection is attacked Only when this fails does the embankment itself starts to erode, which is normally a faster process than erosion of the surface protection Exceptions exist in the case of internal erosion where the soil matrix within the embankment body is eroded and particles start migrating internally causing stability loss and voids, eventually leading to piping The effect of repetitive loading and stress concentration around non-homogeneities in vegetation is related with the concept of progressive collapse It can be seen that vegetation (e.g turf) can be weakened by repetitive loading Hence, discontinuous loadings as wave overtopping flow or wave impact has the potential to generate a more critical condition than steady overflow T04-08-03_ErosionofEmbankments_v9_1.doc April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 2.2 Current and Recent knowledge sources 2.2.1 Research Projects A considerable number of research programmes have been undertaken to improve knowledge about breach initiation and development but only a few of these projects specifically consider the performance of vegetation in cover layers Some of the current or recent larger projects and programmes are summarised in Table 2.1 below A more detailed description of the projects and research programmes is available through the summaries provided under Appendix Selected research programmes and projects showing main research topic areas (x) x x x x x x x x Laboratory tests x x Large scale models x x Field data x x x x Research approach seepage/erosion x wave overtopping x x x x x x x wave run-up run-down x wave-impact No specification x Failure modes/actions General Fluvial x x PROJECT EROGRASS Engineering tools… FLOODsite INFRAM IPET RIMAX COMCOAST Type of vegetation Coastal Type of dike Grass Table 2.1 x x x x x x x x x EroGRASS (2007-2008) EroGrass investigated risk-based design and understanding of failure modes for sea dikes and aimed to enhance the limited information on erosion resistance of grass covered dikes and embankments The project comprised large-scale model tests on sea dikes with grass cover investigating the failure of grass cover on the seaward side by wave impacts and wave run-up / run-down and failure of grass cover on the landward side by wave overtopping Aspects of this research was undertaken in collaboration with research under FLOODsite Task (Morris et al., 2009) Engineering tools for safe, efficient hydraulic structures and channels (2008) Improved methods for predicting earthen embankment erosion and failure, and development of generalised hydraulic guidelines and tools for roller compacted concrete spillways used to protect earthen structures from erosion and to increase discharge capacity This will consider quantification of the protective capabilities of vegetation FLOODsite Task (2006-2009) Understanding and predicting failure modes This research collected existing information on defence failure mechanisms and extended knowledge in a number of critical areas by reviewing current international projects and detailed failure mode analysis on the basis of hydraulic model testing and numerical modelling (Allsop et al., 2007) Wave Overtopping Simulator (Infram - 2007) A wave overtopping simulator was developed in response to the need to test wave overtopping performance of grass covered dikes A prototype was developed and tested by Infram as part of the FLOODsite and ComCoast projects (van der Meer, 2006a) The simulator is placed on top of the embankments and flow surges released to simulate wave overtopping processes The performance of grass and sub soil may be assessed through to destruction T04-08-03_ErosionofEmbankments_v9_1.doc April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 Appendix 1: Current Research Details T04-08-03_ErosionofEmbankments_v9_1.doc 15 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 T04-08-03_ErosionofEmbankments_v9_1.doc 16 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 EROGRASS Research Topic Website Contractor / Participants Funder / Client Description Erosion resistance of grass covered dikes and embankments http://www.kyst.dk/erograss Danish Coastal Authority (DCA), Denmark IHE Delft, Netherlands Strathclyde University, UK Tallinn University, Estonia Delft Hydraulics Delft University EC FP6 EroGrass looks into risk-based design and understanding of failure modes of sea dikes and aims to enhance the limited information on erosion resistance of grass covered dikes and embankments The project comprises large-scale model tests on sea dikes with grass cover investigating in the failure of grass cover on the seaward side by wave impacts and wave run-up / run-down and failure of grass cover on the landward side by wave overtopping In general it looks into the improvement of understanding of grass cover behaviour The main objective of the HYDRALAB III project EroGRASS is to perform large scale model tests to investigate in detail the failure of grass cover layers due to (i) wave impact, (ii) wave run-up and run-down flow and (iii) wave overtopping The large scale tests at a prototype dike model will be performed in the Large Wave Flume (GWK) of the Coastal Research Center (a joint centre of the Universities of Hannover and Braunschweig) in Hannover (Germany) The crest height of the dike model will be 5.8 m above the flume bottom The seaward slope is 1:4 and the shoreward slope is 1:3 The dike crest will be m wide The clay layer thickness is 0.8 m on the seaward and landward slope as well as on the dike crest The length of the dike model is m corresponding to the flume width Since it is not feasible to sow grass on the clay layer and wait for a well-established grass cover, grass mats will be peeled at the southern wing dike of the Ribe flood defence system (Denmark) The Ribe flood defence system is located approximately 50 km north of the German-Danish border Grass mats are 2.35 m long, 1.25 m wide and approximately 0.15 m thick The access of the EroGRASS project to the Large Wave Flume in Hannover is funded by the sixth EC framework programme through the Integrated Infrastructure Initiative HYDRALAB III The programme provides user groups access free of charge to the facilities for their research project and covers travel and subsistence costs The programme is intended for short access periods, not exceeding months Keywords Timeframe Contact Grass erosion, dikes, Grass cover layer, grass erosion, large scale tests, dike model, HYDRALAB III, Large Wave Flume (GWK), Coastal Research Center Hannover April 2007 to approximately April 2008 Thorsten Piontkowitz tpi@kyst.dk T04-08-03_ErosionofEmbankments_v9_1.doc 17 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 Engineering tools for safe, efficient hydraulic structures and channels Research Topic Website Contractor / Participants Funder / Client Description Keywords Timeframe Contact Improve methods of predicting earthen embankment erosion and failure http://www.ars.usda.gov/research/projects/projects.htm?ACCN_NO=411569 USDA/HERU United States Department of Agriculture Agriculture Research Service Improve methods of predicting earthen embankment erosion and failure, and develop generalized hydraulic guidelines and tools for roller compacted concrete spillways used to protect earthen structures from erosion and increase discharge capacity Improving methods of predicting earthen embankment erosion and failure will include sub-objectives of quantification and erosion measurement of embankment materials, quantification of protective capabilities of vegetation, development of algorithms and computational models that can be used by the profession to predict earthen embankment erosion and failure causing downstream flooding The development of generalized hydraulic guidelines and tools for roller compacted concrete spillways will include sub-objectives of development of preliminary guidelines for dimensioning converging sidewalls as well as understanding air entrainment, flow bulking and energy dissipation leading to generalized equations for dimensioning stepped spillways, downstream basins and rip-rap protection that will be used by the engineering profession to design spillways earthen embankment erosion 2007 - 2012 Greg Hanson greg.hanson@ars.usda.gov T04-08-03_ErosionofEmbankments_v9_1.doc 18 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 FLOODsite Task Research Topic Website Contractor / Participants Funder / Client Description Keywords Timeframe Contact Publications related to Project Understanding and predicting failure modes www.floodsite.net HR Wallingford, UK WL | Delft, Netherlands Leichtweiss Institut, Germany Technische Universitaet Dresden, Germany Institute for Hydrology and Ecology, UK IBW, Poland INFRAM, Netherlands EC 6th Framework Programme This research aims to both gather existing information on defence failure mechanisms and to extend knowledge in a number of critical areas by reviewing current international projects and detailed failure mode analysis on the basis of hydraulic model testing and numerical modelling of the most relevant failure modes Outcomes comprise Erosion, Failure, Embankment, Initiation, Surface Cover 2006-2009 Mark Morris m.morris@hrwallingford.co.uk Husrin S (2007) Laboratory experiments on the erosion of clay revetment of sea dike due to breaking wave impacts , IHE, Delft, The Netherlands (M4.4) Stanczak G (2006) Laboratory tests on the erosion of clay revetment of sea dike with and without a grass cover induced by breaking wave impact, LWI report 935, LWI - TU Braunschweig, Braunschweig, Germany (contribution to M4.3) Allsop W Kortenhaus A Morris M et al (2007) Failure Mechanisms for Flood Defence Structures, FLOODsite report T04-06-01 Doorn N (2007) Understanding and Predicting Failure Modes: Failure Modes for Revetments T04-07-03 van der Meer J (2007) ComCoast work package 3: Development of alternative overtopping resistant sea defences T04-07-05 Danuta L (2007) Air trapping phenomenon and cracking - model tests on flood embankment T04-07-10 T04-08-03_ErosionofEmbankments_v9_1.doc 19 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 Wave overtopping simulator (Infram) Research Topic Website Contractor / Participants Funder / Client Description Wave overtopping simulator tests a reinforced grass layer on a seadike http://www.infram.nl/infotype/webpage/view.asp?objectID=227 Infram, Netherlands Royal Haskoning, Netherlands Dutch Ministry of Transport, Public Works and Water Management In May 2007 the Ministry of Transport, Public Works and Water Management will use a wave overtopping simulator to test a traditional dike section with grass and a dike section reinforced with a geotextiel that is placed beneath the grass layer In order to make the crest and the inner slope of the dike resistant to wave overtopping, a consortium of Royal Haskoning and Infram came up with the idea to reinforece the grass (Smart Grass Reinforcement) The tests will be taking place in Delfzijl, where on May 2006 the test sections have been made Infram came up with the idea of the wave overtopping simulator Then a prototype was developed and tested by Infram, together with four students Civil Engineering Last june 23th the prototype was demonstrated at the test location of the constructor, "Nijholt Staal & Machinebouw" in Heerenveen The prototype is a full cross-section of the wave overtopping simulator, but only m wide, the actual wave overtopping-simulator will be m wide! It can be loaded then with 14.000 litres of water The simulator will be placed above the dike crest and can simulate the waves overtopping the dike crest The target of this project is to determine if it is possible to protected dikes against wave overtopping This means that the crest and the inner slope of the dike must be able to resist wave overtopping at extreme storm conditions In the future the wave overtopping simulator will be used to determine how long regular grass on a dike can resist overtopping seawater Keywords Timeframe Contact Publications related to Project Overtopping erosion 2007 Van der Meer JW Bernardini P Snijders W Regeling HJ (2006) The wave overtopping simulator De Rouck J van der Meer JW Allsop NWH Franco L Verhaeghe H (2002) Wave overtopping at coastal structures: development of a database towards up-graded prediction methods T04-08-03_ErosionofEmbankments_v9_1.doc 20 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 IPET - Interagency Performance Evaluation Taskforce Research Topic Website Contractor / Participants Funder / Client Description Keywords Timeframe Contact Performance Evaluation of the New Orleans and Southeast Louisiana Hurricane Protection System https://ipet.wes.army.mil/ Interagency Performance Evaluation Task Force U.S Army Corps of Engineers The project comprises an intense performance evaluation of the New Orleans and Southeast Louisiana Hurricane Protection System during Hurricane Katrina IPET applied some of the most sophisticated capabilities available in civil engineering to understand what happened during Katrina and why Their purpose was not just new knowledge, but application of that knowledge to the repair and reconstitution of protection in New Orleans as well as improvement to engineering practice and policies The results of much of the IPET work are largely already in the ground, having been transferred and applied prior to the formal completion of this report • The System: What were the pre-Katrina characteristics of the hurricane protection system (HPS) components; how did they compare to the original design intent? • The Storm: What was the surge and wave environment created by Katrina and the forces incident on the levees and floodwalls? • The Performance: How did the levees and floodwalls perform, what insights can be gained for the effective repair of the system, and what is the residual capability of the undamaged portions? What was the performance of the interior drainage system and pump stations and their role in flooding and unwatering of the area? • The Consequences: What were the societal-related consequences of the flooding from Katrina to include economic, life and safety, environmental, and historical and cultural losses? • The Risk: What were the risk and reliability of the hurricane protection system prior to Katrina, and what will they be following the planned repairs and improvements (Dec 2007) performance evaluation, dike failure 2005-2007 Wayne Stroupe wayne.a.stroupe@usace.army.mil T04-08-03_ErosionofEmbankments_v9_1.doc 21 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 RIMAX, Subject Protection and Control Research Topic Website Contractor / Participants Funder / Client Description Keywords Timeframe Contact Risk Management of Extreme Flood Events www.rimax-hochwasser.de/400.html?&L=1 GeoForschungsZentrum Potsdam (GFZ), Germany Center for Disaster Management and Risk Reduction Technologies (CEDIM), Germany German Federal Ministry of Education and Research (BMBF) The aim of RIMAX is to develop and implement improved instruments of flood risk management by the integration of different disciplines and several participants It focuses on extreme flood events in river basins with mean events with a return period of more than a 100 years and a highly destructive potential Next to other tasks, Subject 3, Protection and Control, deals with: • Dyke safety, monitoring and dyke protection • Management of dams and retention systems • Management of urban infrastructure (water supply, sewage etc.) during floods • Risk-based reliability analysis of flood defence system Extreme Flood, Risk Management, Dike safety 01/2005 – 12/2007 Bruno Merz bmerz@gfz-potsdam.de T04-08-03_ErosionofEmbankments_v9_1.doc 22 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 COMCOAST Research Topic Website Contractor / Participants Funder / Client Description Keywords Timeframe Contact Multifunctional flood management schemes on coastal areas comprising embankments http://www.comcoast.org Rijkswaterstaat, the Netherlands (Lead Partner) Province of Zeeland, the Netherlands Province of Groningen, the Netherlands University of Oldenburg, Germany Environment Agency, United Kingdom Waterways & Seacanal NV, department 'Zeeschelde', Belgium Danish Coastal authority, Denmark Community of Hulst, the Netherlands Waterboard Zeeuwse Eilanden, the Netherlands Waterboard Zeeuws Vlaanderen, the Netherlands EC Interreg North Sea Programme IIIB ComCoast was a European project that developed and demonstrated innovative solutions for flood protection in coastal areas ComCoast created multifunctional flood management schemes with a more gradual transition from sea to land, which benefits the wider coastal community and environment whilst offering economically sound options The ComCoast concept focused on coastal areas comprising embankments Smart grass reinforcement was extensively researched and tested with a wave overtopping simulator on real dikes grass reinforced embankments 2004-2007 Frans Hamer frans.hamer@rws.nl T04-08-03_ErosionofEmbankments_v9_1.doc 23 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 IMPACT Research Topic Website Contractor / Participants Funder / Client Description Keywords Timeframe Contact Publications related to Project Investigation of Extreme Flood Processes and Uncertainty http://www.impact-project.net HR Wallingford, UK Universität Der Bundeswehr Munchen, Germany Université Catholique de Louvain, Belgium CEMAGREF, France Università di Trento, Italy University of Zaragoza, Spain CESI, Italy SWECO Gröner AS, Norway Instituto Superior Technico, Portugal Geo Group, Czech Republic H-EURAqua, Hungary EC FP5 Research into extreme flood processes covering breach formation, flood propagation, sediment movement and modelling uncertainty In addition, investigation of the use of geophysics for the rapid integrity assessment of embankments Specific objectives are to advance scientific knowledge and understanding, and develop predictive modelling tools in four key areas Specifically, WP2, Investigation of breach formation processes includes understanding the formation processes, prediction of breach formation rate (and hence flood hydrograph) and prediction of breach location Research combines field modelling (controlled failure of 6m high embankments) with laboratory modelling (failure of 0.6m high embankments) and numerical model development (comparison of breach model performance worldwide) Breach formation, Dam-break, Emergency management, Erosion, Flood management, Flood propagation, Flood risk management, Modelling, Models, Morphology, Sediments 2001-2004 Mark Morris m.morris@hrwallingford.co.uk Mohamed MAA Samuels PG Morris MW Ghataora GS (2002) Improving the Accuracy of prediction of breach formation through dam and flood emankments, Journal/Event/Publication: Flow 2002 Conference Broich K (2002) Determination of initial conditions for dam erosion due to overtopping and possible integration into a probabilistic design concept, Journal/Event/Publication: Wallingford, Proc Of 2nd IMPACT Wprkshop, Wallingford, UK, 16/17 May 2002 Broich K (2002) Simulation of the IMPACT Dam-break experiments using different calculation methods, Journal/Event/Publication: Proc of 2nd IMPACT Workshop, Mo I Rana, Norway, 12/13 Sep 2002 Broich K (2003) Verfahren zur hydraulischen Berechnung voon Damm- und Deichbruchen, Journal/Event/Publication: Proceeding of national Symposium on “Sicherung von Dammen und Deichen – Handbuch fur Theorie uns Praxis Ed R.A Hermann and J Jensen, ISBM 3-936533-09-1, Universitat Siegen 7.2 Broich K (2003) Sediment transport in breach formation process, Journal/Event/Publication: Proc Of 4th IMPACT Workshop, UCL Louvain-laNeuve, 6/7.11.2003 T04-08-03_ErosionofEmbankments_v9_1.doc 24 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 Dam Safety Interest Group (DSIG) Breach Modelling Project Research Topic Website Contractor / Participants Funder / Client Description Keywords Timeframe Contact Breach model benchmark testing www.ceatech.ca/DSIG.php Dam owners from Canada, United States, Australia, Sweden, France, United Kingdom and Germany DSIG are undertaking a programme of research to • review and identify top performing / top potential breach prediction models • review and collate field and laboratory data for model validation • perform objective breach model benchmark tests Benchmark tests, Breach formation, Dam-break, Embankments, Erosion, Modelling 2005 – 2007 - - - > 2009 - - - > ? Mr Constantine G Tjoumas / infor@ceati.com T04-08-03_ErosionofEmbankments_v9_1.doc 25 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 HR BREACH Research Topic Website Contractor / Participants Funder / Client Description Keywords Timeframe Contact Breach modelling http://www.hrwallingford.co.uk/Corporate%20literature/ NA028%200709%20MWM%20Breach%20modelling.pdf HR Wallingford HR Wallingford HR Wallingford instigated a programme of research and development to produce a numerical model for prediction of breach formation through embankment dams and linear flood defences This in-house project was initiated in 1998 (following the CADAM project) and has resulted in the production of a prototype model (HR BREACH) This model integrates hydraulics and soil mechanics theory and continues to be developed through the IMPACT project and other related studies The longer-term plan for the HR BREACH model is to incorporate the model into existing flow models (1D / 2D) to provide an interactive flood risk management tool In the meantime, use of the model on flood management projects is possible on a case by case basis Embankment erosion, Breach modelling 1998-2009 Mark Morris m.morris@hrwallingford.co.uk T04-08-03_ErosionofEmbankments_v9_1.doc 26 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 EurOtop Research Topic Website Contractor / Participants Funder / Client Description Keywords Timeframe Contact Wave Overtopping of Sea Defences and Related Structures - Assessment Manual http://www.overtopping-manual.com HR Wallingford, UK Infram, Netherlands LWI, Germany BAW, Germany University of Edinburgh, UK Environment Agency, UK German Coastal Engineering Research Council (KFKI) Rijkswaterstaat, Netherlands Expertise Network on Flood Protection The new "European Overtopping Manual" presents the latest techniques and approved methods for establishing overtopping hazards and flooding for an extensive range of structure types It is relevant to shoreline and coastal engineers, most of whom have used the predecessor manuals, "Overtopping of Seawalls: Design and Assessment Manual" (R&D Technical Report W178, 1999), the Dutch "Technical Report: Wave run-up and wave overtopping at dikes" (TAW, 2002 English edition), and the German Die Küste (EAK, 2002) dike failure, overtopping 2007 Dr Tim Pullen t.pullen@hrwallingford.co.uk T04-08-03_ErosionofEmbankments_v9_1.doc 27 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 PRODEICH Research Topic Website Contractor / Participants Funder / Client Description Keywords Timeframe Contact Publications related to Project Probabilistic design method for sea defences http://www.lwi.tu-bs.de/hyku/deutsch/projekte/prodeich.html Leichtweiß-Institut für Wasserbau (LWI), Germany Institut für Grundbau und Bodenmechanik, Uni Essen, Germany BMBF Within the framework of future coastal protection strategies, probabilistic methods will play an important role for determination of failure probability of coastal defence structures They are the basis for risk analysis of flood- and coastal defence (FCD) systems including all integrated FCD elements like dikes, dunes, seawalls, etc as well as special structures and allow for the quantitative assessment of the consequences in a case of failure The research aims to develop a probabilistic design method for sea dikes under consideration of the most important failure modes on the basis of existing deterministic approaches It will allow the design engineer to derive a quantitative prediction of the safety and reliability of a dike for a given timeframe This prediction will be suitable for design purposes as well as for safety assessments of existing dikes Breach formation, Embankments, Failure mechanisms, Flood defence structure, Probabilistic design, Sea dike, Failure analysis, Fault tree, Probabilistic design, Damage analysis, Stability, Failure modes, Failure probability 2000 - 2002 Prof Dr.-Ing Hocine Oumeraci h.oumeraci@tu-bs.de Kortenhaus A Oumeraci H (2002) Probalilistische Bemessungsmethoden für Seedeiche (ProDeich) LWI Bericht, 877 KFKI Signatur: E 34 942 Lit Kortenhaus A Oumeraci H Weissmann R Richwien W (2002) Failure mode and fault tree analysis for sea and estuary dikes Proc 28th ICCE, Cardiff, KFKI Signatur: E 34 930 T04-08-03_ErosionofEmbankments_v9_1.doc 28 April 2008 FLOODsite Project Report Contract No:GOCE-CT-2004-505420 CLASH Research Topic Website Contractor / Participants Funder / Client Description Keywords Timeframe Contact Crest Level Assessment of Coastal Structures by full scale monitoring, neural network prediction and Hazard analysis on permissible wave overtopping www.clash-eu.org Ugent, Department of Roads, Bridges and Coastal Engineering, Belgium FCCD, Ministry of the Flemish Community, Belgium FCFH, Ministry of the Flemish Community, Belgium LWI, Department of Hydromechanics and Coastal Engineering, Germany Aalborg University, Department of Civil Engineering, Denmark Universidad Politécnica de Valencia Departamento de Transportes, Spain MODIMAR, Italy DH, WL/Delft Hydraulics, Netherlands INFRAM, Netherlands RIKZ, Netherlands Manchester Metropolitan University Centre for Mathematical modelling and flow analysis, UK University of Edinburgh, UK HRWallingford, UK EC – Fifth Framework Programme It has been proven that wave run-up is underestimated by small scale model tests due to scale effects Therefore, there is a strong suspicion that wave overtopping will be underpredicted too Full scale measurements on wave overtopping will be carried out at four sites One site will concentrate on the effect of long waves on shallow water Full scale measurement results are simulated by small scale and numerical modelling to quantify and to explain suspected scale effects As no generic prediction method for crest level assessment exists, this project will create one All existing data on wave overtopping will be collected and supplemented with the full scale data and the "white spot" data gathered in this project Information on permissible levels of wave overtopping is poor and vague A hazard analysis (including socio-economic effects) will give a sound answer to the question of safety of pedestrians, vehicles, buildings, etc overtopping, full scale measurements 2002-2004 Prof Dr ir Julien De Rouck, julien.derouck@ugent.be T04-08-03_ErosionofEmbankments_v9_1.doc 29 April 2008 ... simultaneous management of soil type and state and vegetation type and state 3.4 Improve basic knowledge and understanding of vegetation-erosion processes Objective The improve knowledge and understanding... monitoring and dyke protection • Management of dams and retention systems • Management of urban infrastructure (water supply, sewage etc.) during floods • Risk- based reliability analysis of flood. .. societal-related consequences of the flooding from Katrina to include economic, life and safety, environmental, and historical and cultural losses? • The Risk: What were the risk and reliability of the hurricane