WORKSHOP ON FLASH FLOOD AND DEBRIS FLOW RISK MANAGEMENT

IN MEDITERRANEAN AREAS

26th January 2012

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SPONSORED BY

UNIVERSITY OF SALERNO

AUTORITA’ DI BACINO REGIONALE

IN DESTRA SELE

Proceedings

Proceedings of the international workshop on Flash Flood and Debris Flow risk management in Mediterranean areas

University of Salerno Italy26 January 2012

EDITORSMaria Nicolina PapaDaniel Sempere Torres

Jointly organized by:University of Salerno

C.U.G.RI. (Consorzio inter-Universitario per la previsione e prevenzione dei Grandi RIschi)

Autorità di Bacino Regionale in Destra Sele.

Organizing CommitteeVittorio Bovolin

Maria Nicolina Papa

Daniel Sempere-Torres

Stefano Sorvino

Organizing SecretariatMaria Affinita

Giuseppe Benevento

Fabio Ciervo

Sponsored by:Associazione Ingegneri Ambiente e Territorio (AIAT)

Associazione Idrotecnica Italiana

Gruppo 183

Gruppo Italiano di Idraulica

Provincia di Salerno

Società Idrologica Italiana

Financially supported bySistemi di Ingegneria Geotecnica Energetica Ambientale (SINGEA)

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Table of contents

Invited lectures

• Risk management of sediment-induced disasters in japanEgashira, S.

• Contribution of basin authorities of hydrogeological risk mitigationSorvino, S.

• Learning from EFAS to develop european Flash Flood early warning capacityThielen-del Pozo, J.

• Imprints integrated platform for Flash Floods and Debris Flow managementSánchez-Diezma, R.; Llort, X.; Rodríguez, Á.; Ferrer, M.

• A rule-based warning system for Debris Flows: the amalfi coast case studyPapa, M.; Medina, V.; Bateman, A.; Ciervo, F.; Carbone, A.; Gallo, A.; Bregoli, F.

Topic 1: Hydrologic and hydraulic modeling for hydrogeological risk assessment• Flash flood risk assessment following the european water framework directive. The case of marina alta

and marina baja (alicante, spain)Ortiz, E.

• A simple 2d hydraulic model for large scale flood analysisDottori, F.; Todini, E.

• Non linear modelling of the relationship between the runoff coefficient and the catchment state for streamflow simulation and forecastingLongobardi, A.; Villani, P.

• Methodology for risk assessment of flash flood events due to climate and land use changes: application to the llobregat basinVelasco, M.; Cabello, À.; Escaler, I.

• Hydrological impact of forest fires and climate change in a mediterranean basinVersini, P.; Velasco, M.; Cabello, À.; Sempere-Torres, D.

• Reconstruction and numerical modelling of a flash flood event: atrani 2010Ciervo, F.; Medina, V.; Papa, M.N.; Bateman, A.; Trentini, G.

• Experimental study on dam-break flows of dry granular materialPapa, M.; Sarno, L.; Martino, R.

• Rocasca: a contour tracing grid-based algorithm to identify similarity regions and clusters in spatial geographical dataHazenberg, P.; Uijlenhoet, R.

• Linking a physically based model with a stochastic hollow evolution model to improve our understan ding of the spatial and temporal behavior of landslide prone areas and the impact of climate changeHazenberg, P.; Uijlenhoet, R.

• Proidro project (professionisti del monitoraggio ambientale e la sicurezza idrogeologica) Experience of the internship at the autorità di bacino regionale in destra seleSoreca, S.

• The orographic effects on spatial extreme rainfall variability in campania region (italy)Pelosi, A.; Furcolo, P.; Rossi, F.; Villani, P.

• Gis-based definition of the mountains as orographic barriers: from the campania-lucanian range to appennine chain (italy), toward orography of europeGuida, D.; Cestari, A.; Cuomo, A.; Palmieri, V.; Siervo, V.

• Presentation of debris-flow susceptibility models based on statistical learning and extrapolation to a specific debris-flow induced hazard: landslide tsunamiBregoli, F.; Chevalier, G.; Bateman Pinzon, A.

• Wecpos – wave energy coastal protection oscillating system: a new submerged breakwaterDentale, F.; Trezza, C.; Donnarumma, G.

• An innovative numerical procedure to study the maritime structuresDentale, F.; Donnarumma, G.; Pugliese Carratelli, E.

• The vulnerability of the messina province: from giampilieri to saponaraStancanelli, L.; Faraci, C.; Foti, E.; Musumeci, R.; Nicolosi, V.

• Some consideration about the extreme rainfall in a mediterranean areaDe Luca, C.; Rossi, F.; Villani, P.

Topic 2: Operational tools for alert systems

• Development of a dss to improve the flood control in the spanish national river authoritiesOrtiz, E.; Guna, V.

• Probabilistic flood forecast within a time horizonCoccia, G.; Ortiz, E.; Todini, E.

• Nowcasting of orographic rainfall by using doppler weather radarPanziera, L.; Germann, U.

• Flash flood forecasting using simplified hydrological models, radar rainfall forecasts and data assimilationSmith, P.; Panziera, L.; Beven, K.

• Use of “series distance” for identification of behavioral members in ensemble flash-floods nowcastingZappa, M.; Fundel, F.; Liechti, K.; Germann, U.; Ehret, U.

• The european precipitation index based on simulated climatology – performance assessment for extreme rain-storm and flash flood early warning in europeAlfieri, L.; Thielen Del Pozo, J.

• Development of an operational flood warning system in the guadalhorce basin (andalucia, spain): first results and possible connection with the european flood alert system (EFAS)Versini, P.; Santiago-Gahete, A.; Sempere-Torres, D.

• Portability of a realtime flood forecasting systemSchmid, M.; Liechti, K.; Zappa, M.; Fundel, F.

Topic 3: Best strategies for hydrogeological risk mitigation

• Check dams as mitigation approach for reducing debris flow amplificationRossi, F.; Genovese, M.; Viccione, G.; Bovolin, V.

• Floods in italy: if defence works are part of the problem, can river restoration be a solution?Trentini, G.; Monaci M.; Gusmaroli G.; Goltara A.; Pavan S.; Varese P.; Ciervo F.

• Predicting the river morphology after river restoration. The methodology valuriNardini, A.; Pavan, S.

• Urban watershed restoration as a strategy to face flash floods in port-au-prince, HaitiTrentini, G.; Bresciani, R.; Mastropaolo S.

• Applicability of the functional mobility area concept for the management of watercourses in the autorità di bacino in destra sele areaAffinita, M.; Colella, L.; D'onofrio, G.; Fariello, L.; Grimaldi, G.; Iannella, S.; Lombardi, G.; Minotta, C.; Moretta, F.

EU Directive on the assessment and management of Flood risks

List of Authors

FOREWORD

3rd IMPRINTS International Workshop on flash flood and debris flow risk management in Mediterranean areas.

Salerno (January, 26 2012)

“The key to successful flash flood forecasting is organization ”(WMO Report nº 18; 1981).

Floods are the most frequent natural disaster worldwide and the major natural hazard in Europe in terms of social and economic impacts. In the last 15 years, Europe has suffered over 100 major damaging floods which have caused more than 1,000 casualties, affected more than 3.4 million people, from which about half a million have been displaced, and at least €25 billion in insured economic losses. Additionally, floods also cause important environmental impacts since they heavily affect the quality of water bodies and can mobilize large amounts of sediments and pollutants (including Combined Sewer Overflows, CSO, events in large cities).

Flash Floods (floods that have a very rapid onset) are the most devastating of all floods, heavily affecting the regions characterised by steep slopes and heavy rainfall. Although there is a tendency towards a reduced annual number of deaths, both in Flash Floods and associated Debris Flow, on average these events kill more people worldwide than any other natural disaster. Moreover, Flash Floods are localized phenomena that occur in watersheds of a few hundred square kilometres or less and with response times of a few hours or less, leaving extremely short lead times for warnings. Although Flash Floods have traditionally been associated to mountainous and Mediterranean regions, in fact is now admitted that Flash Floods can occur in any of the hydroclimatic regions of Europe.

During last 50 years important efforts to improve flood warning systems have been carried out by the scientific, institutional and administrative sectors, as well as by engineering practice. As a consequence, significant advances have been made in the body of knowledge, the methodologies and the technologies for improved flood forecasting. Thus in the context of medium to large river basins (in which response times are of the order of tens of hours) there has been a clear improvement in flood forecasts, warnings and public preparedness for reducing casualties and losses. However, the achievements made for FF forecasting have been less impressive due to the fast evolution of these phenomena, which give very short times to react in an efficient manner to manage the induced risks. And, as it has been recognized by the WMO Secretary-general in the conclusions of the First international flash flood workshop, “flash flood forecasting is one of the most difficult problems facing the hydrological and meteorological forecasters at present”.

The European Project IMPRINTS (IMproving Preparedness and RIsk maNagemenT for flash floods and debriS flow events, FP7-ENV-2008-1-226555, 2009-2012), has developed a number of methodologies to improve preparedness and operational risk management for Flash Floods and Debris Flow events. One particularity of the IMPRINTS project has been its orientation to transfer the scientific advancements in flash flood forecasting of the last decades into methodologies and tools that could be used by practitioners of the emergency agencies and utility companies in their tasks of flash flood risk management. Thus, one of the major outcomes is the development of an advanced prototype of IT platform oriented to be used by water authorities around Europe.This prototype will be ready at the end of the project and will be a powerful platform to support the implementation of the Directive 2007/60/EC on flood risks.

This 3rd Workshop, brilliantly organised by the University of Salerno, is an special contribution of the IMPRINTSresearchers to promote the dissemination of these methodologies and tools, and to advance in one of the central objectives of our project: to connect researchers, practitioners and interested users (stakeholders) filling the gap between what we know at the scientific level and what we can do in practice.

The interaction and the discussions we will raise during this event will help us to increase our awareness about the flash floods and debris flow risk and will be a powerful way to help our society to face the challenges that the implementation of the Flood Risks directive represents.

This workshop, together with those organised in Barcelona (2010), Toulouse (2011) and Brussels (to be held in September 2012) as well as the videos on Flash Floods and Debris Flow Risk Management we are presenting, are the IMPRINTS partners’ contribution to this long run that is to learn how to adapt ourselves to better living with the risk in our regions.

Prof. Daniel Sempere TorresIMPRINTS Coordinator

PREFACE

The international workshop on flash flood and debris flow risk management in Mediterranean areas was held at Salerno University, Italy, on the 26th of January 2012. The Conference was jointly organized by the University of Salerno, the C.U.G.RI. (Consorzio inter-Universitario per la previsione e prevenzione dei Grandi RIschi) and the Autorità di Bacino Regionale in Destra Sele.

The workshop was framed in the activities of the Collaborative Project IMPRINTS (IMproving Preparedness and RIsk maNagemenT for flash floods and debriS flow events), supported by the European Community Seventh Framework FP7-ENV-2008-1-226555). Both C.U.G.RI. and Bacino Regionale in Destra Sele are partners of the Imprints group.

The main objective of the workshop was to raise a joint reflection between researchers, practitioners, stakeholders and risk management agencies on the best strategies for the implementation of the Floods Directive (2007/60/EC) of the European Parliament in the peculiar contest of the Mediterranean areas.

The Floods Directive requires Member States to draw up maps identifying all areas exposed to flooding risk and indicating the probability and the potential damage for local populations, property and the environment, by the end of 2013. Moreover it requires preparing and implementing flood risk management plans for each river basin district including management measures focusing on reducing the probability of flooding and the potential consequences of flooding by the end of 2015.

Flash flood and debris flow events affect extensive areas in Mediterranean areas causing a major natural risk. In some areas, the morphological, geological and climatic conditions leading to flash flood and debris flow formation are quite widespread and extensive downstream areas result being prone to risk. In these cases, the risk reductions through the building of structural countermeasures may not only be too expensive but also create environmental concern. Moreover, in many cases, the rigid topography of the interested areas, or the lack of space, makes it difficult to find construction countermeasure solutions. For these reasons in many cases, non structural countermeasures, such as warnings through real time hazard assessment and civil protection measures are more suitable in reducing the risks. For these reasons the attention was particularly focused on the recent scientific advancement on operational warning systems.

A special attention has been also devoted on the integration of the risk reduction with the increasing of the ecological status of rivers (as required by the 2000/60/EC Water Directive and 2007/60/EC Floods Directive). In many cases, the management of the flood risk may be achieved in a cost-effective way, giving back more room to the river and restoring its erodible corridor and floodplain, thus obtaining also the important result of improving the ecological status of the rivers.

The workshop had oral sessions with invited speakers and poster sessions. The poster sessions were:

1. Hydrologic and hydraulic modeling for hydrogeological risk assessment2. Operational tools for alert systems

3. Best strategies for hydrogeological risk mitigation

Maria Nicolina PapaAssistant Professor at Salerno University

Invited Lectures

RISK MANAGEMENT OF SEDIMENT-INDUCED DISASTERS IN JAPAN

Egashira, S.(1)

(1) NEWJEC Inc. and Graduate Research Institute for Policy Studies, River Engineering, Osaka, JP. E-mail: egashirasn@newjec.co.jp

Some study topics conducted in Japan and IMPRINTS are introduced with attention focused on importance of non-structural measures in risk management of sediment induced disasters.In Japan, non-structural measures have been conducted actively due to geological, topological, meteorological conditions, and are also supported by the law for preventing sediment related disasters. Correspondingly, Japanese experiences and field data will be useful for conducting the present study.To introduce a method to prepare a hazard map, governing equations described in 2-D form for debris flows are illustrated. In addition, run-out process of debris flow computed by the numerical method composed of the introduced equations are introduced. Such numerical results would be useful for preparing the hazard map and, thus useful for land use corresponding to the classified risk ranks. Scientific tools and methods can be transfered mutually. However, the results obtained from the methods would be used and applied to reduce and mitigate disasters in different ways, corresponding to different impacts of sediment events on region toregion, country to country......

CONTRIBUTION OF BASIN AUTHORITIES OF HYDROGEOLOGICAL RISK MITIGATION

Sorvino, S.(1)

(1) Basin Regional Authority Sele Southern Campania, Napoli, IT. E-mail: segretario.generale@abds.it

The Basin Authorities of Campania, were established by L.183 /89 and, in its implementation, with LR 8 / 94. Waiting the reorganization referred to article 1 of L 13/2009, the Regional Basin Authority in Right Sele, in the Left Sele and interregionalSele, are to join in the only Basin Authority Regional Sele Southern Campania (L.R. 4 / 11) in the territory, which will have a surface of approximately 5600 sq km, include 173 municipalities, 21 of which are Lucan.. The area has great criticalhydrogeological conditions manifested by a wide range of failures, in the southern part of the territory there are mostly landslide phenomena characterized by slow kinematic (earth slide, earth flow, creep), while in the north, fast kinematic landslides prevail (rock fall e debris flow) with particular reference to the Amalfi Coast. For this reason, the Offices for the soil defense, especially the Basin Authority, make a series of coordinated and integrated actions, for the hydrogeological reorganization of the territory.The implementation of the PAI (Plan for Hydrogeological Excerpt) represents an important intervention of "non-structural" mitigation of geological risks. The PAI is implemented through short-term measures and actions from medium to long term. Theshort term actions include measures to provide information to the public through workshops and outreach activities. These actions also include the involvement of the IMPRINTS that aims to contribute to reducing the loss of human lives and economic damage,operating under the operational readiness and risk management linked to the effects due to flash floods and debris flows. Toachieve this goal, the project has been organized to produce methods and means used by experts Civil Defense and Authorities responsible for the management of risks associated with these phenomena. Among the short-term actions, it should be noted that the Authority provides support to Local Authorities for the preparation of Emergency Plans provided by art. 65 - D.lgs 152/06. The medium and long term actions include the activation of specific protocols with the Region and other Agencies for the integrated management of landslide risk in accordance with the provisions in D.lgs 152/06. These actions include the realization of territorial garrisons for emergency management in supporting the local structures of civil protection, to which the Basin Authority participates, especially, to provide scenario’s risk. The PAI, finally, is implemented through three-year programsintervention, drafted in accordance with the guidelines and objectives of the PIA itself. The new structure dictated by regional legislation, the Basin Authorities will ensure consistent and shared actions, and therefore more effective, in the delicate task of defending the territory from hydrogeological instability.

LEARNING FROM EFAS TO DEVELOP EUROPEAN FLASH FLOOD EARLY WARNING CAPACITY

Thielen-del Pozo, J.(1)

(1) European Commission , Joint Research Centre, Ispra (VA), IT. E-mail: Jutta.thielen@jrc.ec.europa.eu

The European Flood Awareness System (EFAS) has been a success story for European Research : initiated as an EU research project, the European Flood Forecasting System (EFFS, FP5, 1999-2002) project sparked off a number of follow up initiatives amongst which FEWS and EFAS are well known projects that have found widespread acceptance across Europe over the past 10 years. The European Flood Awareness System (EFAS) has been developed since 2003 and currently runs pre-operationally at the Joint Research Centre of the European Commission. In 2012 it is being transferred to an operational state and will be providing daily, realtime flood information across Europe as complementary flood information to Regional National Water authorities andto the Monitoring and Information Centre (MIC), the operational heart of the Community Mechanism for Civil Protection led by the European Commission. EFAS aims at drawing early attention to the possibility of flooding in 3-10 days in advance for larger and mostly trans-national river basins.Building a European system for early flood warning on European scale required the development of several important concepts and methodologies that are not limited to riverine floods only. Probabilistic approaches to extend the limits of predictability for severe weather events and consequent flooding on different scales are important building blocks of EFAS that are equally useful for raising awareness of an increased probability for flashfloods 24-36 hours ahead, thus complementing local systems based on nowcasting and remote sensing information. The possibility of simulating entire regions rather than single catchments is particularly useful for flashfloods where rainfall predictions and detection have a high degree of spatial uncertainty. This presentation will step through the development of the European Flood Awareness System from a research study to an operationaltool and demonstrate potential cross-links and benefits of flashflood forecasting as part of the IMPRINTS project.

IMPRINTS INTEGRATED PLATFORM FOR FLASH FLOODS AND DEBRIS FLOW MANAGEMENT

Sánchez-Diezma, R.(1); Llort, X.(2); Rodríguez, Á.(3); Ferrer, M.(4)

(1) HYDS, -, Barcelona, ES. E-mail: rafael@hyds.es(2) HYDS, -, Barcelona, ES.(3) HYDS, -, Barcelona, ES.(4) HYDS, -, Barcelona, ES.

One of the objectives of the IMPRINTS FP7 European project is the development of a platform for Flash Flood [FF] and Debris Flow [DF] management. Thas platform integrates the algorithms, tools and methodologies developed within the project under a common design.The aim of the platform is to facilitate the interpretation of all the information related to the FF/DF events and help the practitioners on the decision making process in operational environments.In the development of the IMPRINTS platform, a big effort has been devoted to translate scientific results of the subprojects [SP] 1-4 to practical tools within uniform working methodology and look and feel, taking into account the guidance of end users. These specifications implied to adapt the platform to work over different resolutions, time steps, forecasting horizons, and many other parameters depending on the source of the information and the test bed basin applied.Underlying the platform, there is a database able to manage the different algorithm outputs over the different test bed basins and transform to a common format for visualization and dissemination purposes. The database also manages the particularities of each algorithm output and the information of the different client accounts.An advanced web visualization tool completes the platform and provides specific information to each client logged in.In the current status, the IMPRINTS platform is able to manage most of the outputs of the algorithms developed in the SPs 1-4and visualize all these information under a common viewer. Those algorithms have been implemented and tested on the differenttest beds, taking into account its characteristics and the availability of each algorithm outputs.

A RULE-BASED WARNING SYSTEM FOR DEBRIS FLOWS: THE AMALFI COAST CASE STUDY

Papa, M.(1); Medina, V.(2); Bateman, A.(3); Ciervo, F.(4); Carbone, A.(5); Gallo, A.(5); Bregoli, F.(3)

(1) University of Salerno, Dept. of Civil Engineering, Salerno, IT. E-mail: mnpapa@unisa.it(2) Technical University of Catalonia (UPC), Sediment Transport Research Group, Barcelona, ES.(3) Technical University of Catalonia (UPC), Sediment Transport Research Group, Barcelona, ES.(4) University of Salerno, Dept. of Civil Engineering, Salerno, IT.(5) GEORES, Studio Geologico Associato, Salerno, IT.

Debris and mud flow events may affect vulnerable areas causing a major natural risk. In some areas, the morphological, geological and climatic conditions leading to debris flow formation are quite widespread and extensive downstream areas result being prone to debris flow risk. In these cases, the risk reductions through the building of structural countermeasures may not only be too expensive but also create environmental concern. Moreover, in some cases, the rigid topography of the interested areas, or the lack of space, makes it difficult to find engineering design and construction countermeasure solutions.For these reasons in many cases, non structural countermeasures, such as warnings through real time hazard assessment and civil protection measures are more suitable in reducing the risks.The aim of the present work is to develop a system capable of providing debris flow warnings in areas where historical events data are not available as well as in the case of changing environments and climate. For these reasons, critical rainfall threshold curves are derived from mathematical and numerical simulations rather than the classical derivation from empirical rainfall data. The operational use of distributed model, based on the stability analysis for each grid cell of the basin, is not feasible in the case of warnings due to the long running time required for this kind of model as well as the lack of detailed information on the spatial distribution of the properties of the material in many practical cases.Moreover, with the aim of giving debris flow warnings, it is not necessary to know the distribution of instable elements along the basin but only if a debris flow may affect the vulnerable areas in the valley. The capability of a debris flow of reaching the downstream areas depends on many factors linked with the topography, the solid concentration, the rheological properties of the debris mixture and the flow discharge as well as the occurrence of liquefaction of the sliding mass. In relation to a specific basin, many of these factors may be considered as not time dependent. The most rainfall dependent factors are flow discharge and correlated total debris volume. In the present study, the total volume that is instable, and therefore available for the flow, is considered as the governing factor from which it is possible to assess whether a debris flow will affect the downstream areas or not. The possible triggering debris flow is simulated, in a generic element of the basin, by an infinite slope stability analysis. The groundwater pressure is calculated by the superposition of the effect of an “antecedent” rainfall and an “event” rainfall. Thegroundwater pressure response to antecedent rainfall is used as the initial condition for the time-dependent computation of the groundwater pressure response to the event rainfall.Antecedent rainfall response is estimated in the hypotheses of low intensity and long duration, thus assuming steady state conditions and slope parallel groundwater flux. The short term response to rainfall is assessed in the hypothesis of verticalinfiltration. The simulations are performed in a virtual basin, representative of the one studied, taking into account the uncertainties linked with the definition of the characteristics of the soil. The approach presented is based on the simulation of a large number of cases covering the entire range of the governing inputdynamic variables. For any possible combination of rainfall intensity, duration and antecedent rain, the total debris volume, available for the flow, is estimated. The resulting database is elaborated in order to obtain rainfall threshold curves. Whenoperating in real time, if the observed and forecasted rainfall exceeds a given threshold, the corresponding probability of debris flow occurrence may be estimated.

References

Maria Nicolina Papa, Vicente Medina, Allen Bateman (2011). Derivation of critical rainfall thresholds for debris flow warnings through mathematical and numerical modeling. In: 5th International Conference on Debris-Flow Hazards Mitigation, Mechanics, Prediction and Assessment. 14-17 June 2011, PadovaFrancesco Bregoli, Fabio Ciervo, Vicente Medina, Allen Bateman, Marcel Hürlimann, Guillame Chevalier, Maria Nicolina Papa (2010). Development of preliminary assessment tools to evaluate debris flow hazard. XVIII International Conference on computational methods in water resources CMWR2010 June 21-24, 2010, Barcelona, SpainMaria Nicolina Papa, Giuliano Trentini, Antonio Carbone, Antonio Gallo (2011). An integrated approach for debris flow hazard assessment - a case study on the amalfi coast - campania, italy. In: 5th International Conference on Debris-Flow Hazards Mitigation, Mechanics, Prediction and Assessment. 14-17 June 2011, Padova

Topic 1:Hydrologic and hydraulic modeling for

hydrogeological risk assessment

FLASH FLOOD RISK ASSESSMENT FOLLOWING THE EUROPEAN WATER FRAMEWORK DIRECTIVE. THE CASE OF MARINA ALTA AND MARINA BAJA (ALICANTE, SPAIN).

Ortiz, E.(1)

(1) Idrologia e Ambiente Srl, Idrologia, Napoli, IT. E-mail: enrique.ortiz@idrologiaeambiente.com

The European Water Framework Directive (2007/60), concerning flood risk assessment and management, fixes three stages to follow for the preparation of a basin management plan against floods. The first stage is the preliminary flood assessment, in order to identify the potential flood risk zones, the second one schedules a detailed hazard and risk cartography of these zones, and the third regards the elaboration of a management plan in order to reduce the flood risk where appropriate. For these reasons, theRiver Júcar Water Board (Spain) commissioned a study in order to analyse the effect of flooding on different urban centres andhydraulic structures of two counties, Marina Alta and Marina Baja (Alicante, Spain), aiming to redact a basin management planagainst risk. This zone is particularly known for especially high rainfalls (the “Cold Drop” effect) which suffered recent extreme flash floods, whose economical impact was very relevant, due to the high population density and tourism infrastructures.The first stage, identification of potential flood risk zones, was carried out by coupling a stochastic extreme rainfall generation model (RAINGEN, Salsón and García Bartual, 2003) for extreme rainfall scenarios generation, a conceptual distributed hydrological model (TETIS, Francés et al, 2007) for rainfall-runoff modelling, and a hydraulic model (InfoWorks CS), for bidimensional modelling of flooded regions. The rainfall-runoff model provided the boundary conditions for the hydraulic modelling. 22 hydraulic models were set up with a total of 70 km2 of detailed bidimensional modelling based on digital elevation models 1x1m obtained by Lidar. Five synthetic flood events were chosen and simulated for each flood zone, corresponding to 10,25, 50, 100 and 500 years of return period. The results are five maximum water level maps, associated with the 10, 25, 50, 100 and 500 years of return period, for each one of the flood zones. In order to analyse the vulnerability and the economic impact of flooding, the European Water Framework directive was followed: the flood hazard was evaluated considering hydraulic variables (such as the maximum water level) and other variables such as the sediment production and the vulnerability was computed taking into account economical, social and environmental variables (number of affected inhabitants, possible sources of pollution, etc)In order to evaluate the vulnerability as previously explained, it was necessary to elaborate water level – economical damage curves, which were calibrated following the economical damages subsequent to historical floods. Integrating these curves with the results of the hydraulics studies, the risks maps are obtained. Once determined the risk of the studied zones the next step is the elaboration of a management plan in order to reduce the flood risk.

A SIMPLE 2D HYDRAULIC MODEL FOR LARGE SCALE FLOOD ANALYSIS

Dottori, F.(1); Todini, E.(2)

(1) University of Bologna, Department of Earth, Geological and Environmental Sciences, Bologna, IT. E-mail: francesco.dottori@unibo.it

(2) University of Bologna, Department of Earth, Geological and Environmental Sciences , Bologna, IT.

The Directive 60/2007 of European Union introduced important modifications in flood risk evaluation and management. In particular, the Directive prescribes the development of flood hazard and risk maps at river basin scale in all European countries. Considering this framework, we developed a simple but effective 2D flood inundation model based on a simplified finite volume scheme, called CA2D. Several application to both numerical and real case studies were performed to investigate the model performance under different flow conditions. Thanks to the simple structure and different techniques to improve stability, the model is fast and particularly suited for large scale flood analysis. In particular, the code structure allows for massive code parallelization. Experiments proved that the model is able to reproduce both slow and fast flood events with a good accuracy in terms of water depths and velocity. Therefore, the model can be applied to simulate a wide range of flood event types, including lowland floods and flash floods in urban areas.

References

Dottori, F., Todini, E., 2011. Developments of a flood inundation model based on the cellular atomata approach: testing different methods to improve model performance. Physics and Chemistry of the Earth 36 (2011) 266-280.Dottori, F., Todini, E., 2012. Testing a simple 2D hydraulic model in an urban flood experiment. Hydrological processes, underreview.

NON LINEAR MODELLING OF THE RELATIONSHIP BETWEEN THE RUNOFF COEFFICIENT AND THE CATCHMENT STATE FOR STREAMFLOW SIMULATION AND FORECASTING

Longobardi, A.(1); Villani, P.(2)

(1) University of Salerno, Department of Civil Engineering, Fisciano (SA), IT. E-mail: alongobardi@unisa.it(2) University of Salerno, Department of Civil Engineering, Fisciano (SA), IT.

The relationship between event rainfall and catchment runoff is strongly non linear. Initial conditions, that is the catchmentwetness state prior to a rainfall event, are the main cause of non linearity: the magnitude of the catchment response to a particular rainfall event would be different depending on wet or dry initial soil conditions. The hydrological system response can be summarized through the runoff coefficient Cf, that is the proportion of total rainfall that becomes runoff during a storm event.With the introduction of this index, it can be possible to delineate a relation between Cf and the catchment state, typically non linear, which would be called the catchment state curve. The delineation of the catchment state curve is relevant to simulation and forecasting problems because, once the catchment state is known, the runoff coefficient is known and consequently, for an observed or estimated rainfall volume, the surface runoff volume is also quantifiable. On a practical base, the catchment state, straightforwardly associated to soil wetness conditions, is not available and when measurable, a lot of monitoring points are indeed needed to get either an average or an antecedent catchment state for a particular watershed. Alternatively, antecedent soil moisture conditions can be simulated using models (either lumped or distributed), provided standard climate data are available, or inferred from some other easily measurable hydrological variables. The calibration of the catchment state curve can be empirically obtained when rainfall and streamflow data are available. Butmodelling tools can be alternatively used. With reference to a conceptual lumped model, it is possible to delineate similarities between model parameters and the state curve shape. If the system is made up of two linear reservoirs, streamflow becomes thesum of two components, a fast and a slow component, which are the results of different dominant processes. The slow contribution to stream flow is mainly represented by base flow and deep subsurface flow, whereas the fast contribution is mainly represented by shallow subsurface flow and surface flow. The hydrograph is split between the two components, with different response times, according to a recharge coefficient. The slow component is β proportional to the system input, whereas the fast component is 1-β proportional to the system input. It can be possible to show that the recharge parameter is variable on a seasonal base, gaining the role of a dynamic index of the rainfall-runoff transformation.

References

A. Longobardi, P. Villani, R.B. Grayson and A. W. Western (2003). On the relationship between runoff coefficient and catchment initial conditions. In Post, D.A. (ed) MODSIM 2003 International Congress on Modelling and Simulation. Vol. 2, pp. 867-872. Modelling and Simulation Society of Australia and New Zealand, July 2003, ISBN 1-74052-098-X.P. Furcolo, M. Guglielmi, A. Longobardi, P. Villani (2006). Modellazione non lineare della relazione tra coefficiente di deflusso e stato del sistema. Metodi Statistici e Matematici per le Analisi Idrologiche, D. Piccolo e L. Ubertini (eds.), CNR-GNDCI Pubblicazione n. 2908, pp. 49-57.A. Longobardi, P. Villani (2006). Seasonal response function for daily streamflow investigation, Physics and Chemistry of theEarth, 31, 1107-1117.

METHODOLOGY FOR RISK ASSESSMENT OF FLASH FLOOD EVENTS DUE TO CLIMATE AND LAND USE CHANGES: APPLICATION TO THE LLOBREGAT BASIN

Velasco, M.(1); Cabello, À.(2); Escaler, I.(3)

(1) CETaqua, U2, Cornellà de Llobregat, ES. E-mail: mvelasco@cetaqua.com(2) CETaqua, U2, Cornellà de Llobregat, ES.(3) CETaqua, DT, Cornellà de Llobregat, ES.

The work described here is part of the IMPRINTS project, included in the 7FP of the EC. In the frame of this project, impacts of future changes (including climate, land-use and socioeconomic changes), on flash floods (FF) and debris flows risk are analysed.Extreme events are expected to increase all over Europe due to global change. As the impacts that FF currently provoke are strong and may be worsened because of the future changes, the development of methodologies of risk assessment of FF events is a subject of major social interest.The case studied here is the Llobregat River basin, with a surface of approximately 5.000 km², located in Catalonia, in the Northeast of the Spain. Due to the rough orography of the region and the reduced size of most of the Llobregat sub-basins, the hydrologic response time of these watersheds is around a few hours. The basin presents the typical Mediterranean climate, where one third of the average annual precipitation can usually fall in less than 48h. That is why FF develop rapidly during the convective storms and suddenly inundate the terminal flood plains. It is widely agreed that natural risks are the product of hazard and its consequences. Within this approach, risk is a function of hazard (represented by extreme river discharge and flood water depth), exposure (represented by the assets that are present at each location) and vulnerability (susceptibility of the exposed structures/people in contact with the damaging natural event, normally expressed by a monetary value). If any of these factors increases, the level of risk also increases. The hazard level produced by a flood is expressed in terms of its intensity and probability, which can be expressed by the water depth and return period of a flood event. To avoid using hydrologic models, the hazard maps of the PEFCAT project developed by the ACA were used. As the aim of this work was to determine the future risk scenarios, a transformation of the current hazard maps was undertakenusing future climate scenarios. Therefore, the scenarios developed by SMC were used (Barrera-Escoda and Cunillera, 2010). These precipitation projections were analysed by fitting a GEV extremes function (Cabello et. al, 2011), and then the PEFCAT hazard maps were given new return periods.Urban land-use scenarios were simulated using the MOLAND cellular automata model (Barredo et al., 2003). In order to obtain vulnerability maps, a monetary value was assigned to each land-use type by using a classification based on the total economic value of exposed assets for each land-use class.Finally, overlaying these datasets enabled to obtain risk maps. This was done for each cell, by multiplying the different weights defined by a qualitative simplified risk methodology. From these future risk maps, it was possible to identify new potential risk zones, where more emphasis should be given when implementing adaptation measures.

References

Barredo, J. I., Kasanko, M., McCormick, N. and Lavalle, C. (2003), Modelling dynamic spatial processes: Simulation of urban future scenarios through cellular automata. Landscape and Urban Planning, 64(3), 145-160.Barrera-Escoda, A. and Cunillera, J. (2010), Study of the precipitation evolution in Catalonia using a mesoscale model (1971–2000). Advances in Geosciences, 26, 1-6.Cabello, A., Velasco, M., Barredo, J.I., Hurkmans, R.T.W.L., Barrera-Escoda, A., Sempere-Torres, D., and Velasco, D. (2011), Assessment of future scenarios of climate and land-use changes in the IMPRINTS test-bed areas, Environmental Science & Policy, In Press, Available online 2 April

HYDROLOGICAL IMPACT OF FOREST FIRES AND CLIMATE CHANGE IN A MEDITERRANEAN BASIN

Versini, P.(1); Velasco, M.(2); Cabello, A.(3); Sempere-Torres, D.(4)

(1) UPC, CRAHI, Barcelona, ES. E-mail: pierre-antoine.versini@crahi.upc.edu(2) CetAqua, CRAHI,,,CRAHI, Barcelona, ES.(3) CetAqua, CRAHI,,,CRAHI, Barcelona, ES.(4) UPC, CRAHI, Barcelona, ES.

Mediterranean basins affected by flash floods usually respond rapidly to intense rainfall because of steep slopes, impermeablesurfaces, and/or saturated soils. This fast response can be amplified by forest fires affecting the basin: during the years right after a fire, the effects induced by a forest fire in the hydrological response may be similar to those produced by the growth of impervious areas. Moreover, climate change and global warming in Mediterranean areas can imply consequences on both flash flood and fire hazards, by amplifying these phenomena. Based on historical events and post-fire experience, a methodology to map the risk of forest fire has been developed. Moreover, the consequences on the hydrological behaviour for a burnt basin have been interpreted in terms of rainfall-runoff model parameters. Using this modelization, the combined effect of forest fire and climate change has been analysed in order to assess their consequences on flood occurrence. This study has been conducted on the Llobregat basin (Catalonia, Spain), which is frequently affected by flash flood and forest fires. The results show that flood frequency can be significantly altered by forest fires. Also, it has been analysed how climate change may increase the occurrence of both hazards and make more frequent severe flash floods. Based on these results, a rule-based probabilistic forecasting system is developed to study these impacts by combining triggering factors, and to compare to the present situation in probabilistic terms.This work has been supported by The IMPRINTS project, framed in the EC 7th Framework Programme. It has the main objective of contributing to the reduction of loss of lives and economic damage through the improvement of preparedness and operationalrisk management of flash floods and debris flow events. Global change is expected to increase the stress on the entire water cycleand extreme events are likely to increase due to climate change. That is why in the frame of this project, impacts of future changes are analyzed.

RECONSTRUCTION AND NUMERICAL MODELLING OF A FLASH FLOOD EVENT: ATRANI 2010

Ciervo, F.(1); Medina, V.(2); Papa, M.N.(3); Bateman, A.(4); Trentini, G.(5)

(1) Department of Civil Engineering, University of Salerno, Fisciano (SA), IT. E-mail: fciervo@unisa.it(2) Grupo de Investigación en Transporte de Sedimentos, Polytechnic University of Catalunya, Barcelona, ES.(3) Department of Civil Engineering, University of Salerno, Fisciano (SA), IT.(4) Grupo de Investigación en Transporte de Sedimentos, Polytechnic University of Catalunya, Barcelona, ES.(5) Elementi Associeted, Firenze, IT.

The work intends to reproduce the flash-flood event that occurred in Atrani (Amalfi Coast – Southern Italy) on the 9 September 2010. In the days leading up to the event, intense low pressure system affected the North Europe attracting hot humid air masses from the Mediterranean areas and pushing them to the southern regions of Italy. These conditions contributed to the development of strong convective storm systems, Mesoscale Convective Systems (MCS) type. The development of intense convective rain cells, over an extremely confined areas, leaded to a cumulative daily rainfall of 129.2 mm; the maximum precipitation in 1hr was 19.4mm. The Dragone river is artificially forced to flow underneath the urban estate of Atrani through a culvert until it finally flows out into the sea. In correspondence of the culvert inlet a minor fraction of the water discharge (5.9m3/s), skimming over the channel cover, flowed on the street and invaded the village. The channelized flow generated overpressure involving the breaking of the cover of culvert slab and caused a new discharge inlet on the street modifying the downstream flood dynamics. Information acquired, soon after the event, through the local people interviews and the field measurements significantly contributed to the rainfall event reconstruction and to the characterization of the induced effects. In absence of hydrometric data, the support of the amateur videos was of crucial importance for the hydraulic model development and calibration. A geomorphology based rainfall-runoff model, WFIUH type (Instantaneous Unit Hydrograph Width Function), is implemented to extract the hydrograph of the hydrological event. All analysis are performed with GIS support basing on a Digital Terrain System (DTM) 5x5m. Two parameters have been used to calibrate the model: the average watershed velocity (Vmean = 0.08m/s) and hydrodynamic diffusivity (D=10E-6 m2/s). The model is calibrated basing on the peak discharge assessed value (98.5 m3/s) and the observed hydrological response time (1hr). The flood hydrograph, thus obtained, constituted the upstream boundary condition for the simulation of the propagation processes in the urban area. The flow propagation has been simulated through 2D FLATModel code. FLATModel is a numerical code forsolving the 2D system shallow-water equations; it belongs to the family of explicit Godunov schemes. In this work the code is tested on unstructured mesh. The unstructured mesh is particularly useful for detailed analysis and small scale hydraulic studies; it allows the adapting of digital surface to complex urban real estate improving significantly the resolution of the simulation results. The use of unstructured meshes also entails a significant reduction of the computational burden allowing the thickening of the cell domain where a better resolution is required. The results of simulations are in good agreement with the field observations, therefore the implemented approach seems suitable for the simulation and prediction of possible future flash flood events in similar context areas.

References

Ciervo F., M.N. Papa, Medina V., Bateman A., Ricostruzione e modellazione numerica di un evento di flash flood: il caso di Atrani 2010, L’Acqua, Italian Hydrotechnic Association (submitted).Medina V., Hürlimann M., Bateman A., Application of FLATModel, a 2D finite volume code, to debris flows in the northeastern part of the Iberian Peninsula, s.l., Landslides, Springer-Verlag Ed., 2007, 5, pp. 127-142.

EXPERIMENTAL STUDY ON DAM-BREAK FLOWS OF DRY GRANULAR MATERIAL

Papa, M.(1); Sarno, L.(2); Martino, R.(3)

(1) Salerno University, Civil Engineering Department, Salerno, IT. E-mail: mnpapa@unisa.it(2) Universlity of Napoli Federico II, Dept. of Hydraulic, Geotechnical and Environmental Engineering, Napoli, IT.(3) Universlity of Napoli Federico II, Dept. of Hydraulic, Geotechnical and Environmental Engineering, Napoli, IT.

Debris flows as well as snow and rock avalanches are fast-moving flows that occur in many areas of the world. They are particularly dangerous to life and property because they move with high velocities, destroy infrastructures in their paths, and often strike without warning.In some real world cases, geophysical flows can be triggered by phenomena that are very similar to a dam break. Water flows generated by a dam break have been widely studied and mathematical models for water dam-break waves are available in many textbooks and research papers. Compared to water dam-break waves, debris flow waves display a wider variability and, for their mathematical description, require models with a much greater complexity. As in the case of clear water, particular attention must be given to their numerical integration because of the frequent developing of steep gradients and shock waves.Owing to this complexity, a number of simplifications are put in place and tested under laboratory conditions: the results of the tests are then used to improve the rheological models that underlie the numerical simulations.In the specific case of debris flows, flows arising from a dam-break-like event of dry granular material can help in the process of model validation. Moreover, a good understanding of the mechanics of dry granular flows is also essential in order to set up two-phase debris-flow models because two separate modelling of the solid and fluid phases are needed. The present work examines dam-break flows of dry granular material and investigates the suitability of the depth-averaged models with particular attention being given to the description of the shear stresses and pressure terms. The experimental results of dam-break flows down a gently sloped channel have been reported. Tests were carried out on both a smooth Plexiglas bed as well as a rough one. Measurements of the flow depth profiles and the front wave position were obtained using two digital cameras. In order to compare the prediction of the depth-averaged approach with granular avalanche tests, a specific mathematical and numerical model was implemented. The momentum equation was modified in order to take into account the resistances due to the side walls.The numerical integration of the shallow water equations was carried out through a TVD finite volume method. In order to address the importance of a good estimate of the stress distribution inside the pile, several numerical simulations were performed, calculating with different formulas the pressure coefficient that relates longitudinal and vertical normal stresses in the momentum equation. The simulations present, in general, agree with experimental data. The differences have been outlined between the smooth and rough bed cases.

References

Luca SARNO, Maria Nicolina PAPA, Riccardo MARTINO (2011). DAM-BREAK FLOWS OF DRY GRANULAR MATERIAL ON GENTLE SLOPES. casa editrice università la sapienza, roma: pp.503- 512, 10.4408/IJEGE.2011-03.B-056: In: 5th

International Conference on Debris-Flow Hazards Mitigation, Mechanics, Prediction and Assessment. 14-17 June 2011, Padova.

ROCASCA: A CONTOUR TRACING GRID-BASED ALGORITHM TO IDENTIFY SIMILARITY REGIONS AND CLUSTERS IN SPATIAL GEOGRAPHICAL DATA

Hazenberg, P.(1); Uijlenhoet, R.(2)

(1) Wageningen, Hydrology and Quantitative Water Management, Wageningen, NL. E-mail: pieter.hazenberg21@wur.nl(2) Wageningen University, Hydrology and Quantitative Water Management, Wageningen, NL.

Over the last decades the amount of spatial geographic data obtained from satellite and radar remote sensing, geographical and other types of spatial information has increased tremendously, making it impossible for a user to examine all in detail. Therefore, a considerable amount of research has focused on smart and efficient solutions to segment a spatial image into its dominant regions, extracting most essential information. The current research presents a new spatial image cluster identification method. The delineation of clusters is performed in two separate steps. First we identify a regions outer contour using the properties of a rotating carpenter square. Secondly we define all inner pixels belonging to a cluster based on the same principle, excluding inner contour regions if necessary. As such, a cluster identification method will be presented which has considerable similarity to some of the tracing type and connected component image segmentation algorithms developed in the literature during the last decade.However, since the characteristic shape of a carpenter square can easily be extended, the algorithm presented here does not strictly label neighboring pixels to the same component only. On the contrary, our algorithm is able to connect non-neighboring pixels for varying pixel distances as well. In addition, since our algorithm takes a continuous grid as input, it is possible to define transition pixels, that connect pixels that belong to a given cluster. Therefore, this newly developed algorithm presents a link between the traditional image segmentation methods implemented on binary grids and the partitional density and grid-based cluster identification methods that use continuous datasets. We will demonstrate the impact of this new cluster identification method for a number of typical geophysical cases ranging from global drought identification to weather radar based precipitation cell delineation.

LINKING A PHYSICALLY BASED MODEL WITH A STOCHASTIC HOLLOW EVOLUTION MODEL TO IMPROVE OUR UNDERSTANDING OF THE SPATIAL AND TEMPORAL BEHAVIOR OF LANDSLIDE PRONE AREAS AND THE IMPACT OF CLIMATE CHANGE

Hazenberg, P.(1); Uijlenhoet, R.(2)

(1) Wageningen University, Hydrology and Quantitative Water Management, Wageningen, NL. E-mail: pieter.hazenberg21@wur.nl

(2) Wageningen University, Hydrology and Quantitative Water Management, Wageningen, NL.

The spatial identification of landslide prone areas and the simulation of their response as a result of intense rainfall has been treated in many scientific papers over the last decades. Generally, the quality of these type simulations is dependent on 1) the complexity of the model, 2) the dominant physical processes assumed to be important, and 3) the amount of data measurements available to calibrate the model. For many environments, limited knowledge with respect to the latter aspect prohibits detailed small scale simulation of landslides and debris flow prone areas. However, by focusing on the most dominant physical processesonly, the amount of input information needed becomes less, enabling one to simulate the impact of extreme precipitation on the triggering of landslides and debris flow within a mountainous region. Unfortunately, due to the assumed simplifications, it is difficult to identify the location of the affected areas within the landscape exactly.In the current study, such a simplified physically based model, the LAPSUS_LS model (Claessens et al., 2007)) was used to identify the dominant landslide prone areas. However, since it is unable to identify the exact locations within a landscape, instead of drawing hard conclusions, from the model results the physical characteristics of the different hollows were obtained. As such, all unstable DEM pixels as simulated by LAPSUS_LS were connected into individual areas from which different hollow characteristics could be identified (e.g. area, local slope, length, upstream area, etc.). These properties were used to initialize a temporal stochastic hollow evolution model, originally developed by D'Odorico and Fagherazzi (2003). Since this hollow evolution model is stochastic, by following this approach, we believe we are not only able to increase our understanding on the general landslide behavior within a landscape, but also obtain information about the general statistical behavior involved as well as how these characteristics change as a result of precipitation regime changes. Such information could not have be obtained using a spatial physically based model only.As an example, we present the impact of this approach for the Linth catchment in Switzerland, a basin in which landslides occur often. Based on the current climate situation, the dominant landslide prone areas were identified. For each of these region, the different physical characteristics were obtained and used to assess the general response properties of the different types of hollows involved as well as their specific statistical characteristics. For the latter, by following this approach it becomes possible to assess the impact of climate change on the occurrence of landslides within the region during the 21st century.

PROIDRO PROJECT (PROFESSIONISTI DEL MONITORAGGIO AMBIENTALE E LA SICUREZZA IDROGEOLOGICA)EXPERIENCE OF THE INTERNSHIP AT THE AUTORITÀ DI BACINO REGIONALE IN DESTRA SELE

Soreca, S.(1)

(1) Stage Autorità di Bacino in Destra Sele, -, Benevento, IT. E-mail: salvatore.soreca@gmail.com

An interesting and useful internship at the Autorità di Bacino Regionale in Destra Sele has been carried out between June andDecember 2011 by the author of the present Poster. That internship has been promoted by the ProIdro Project (Professionisti del Monitoraggio Ambientale e la Sicurezza Idrogeologica). ProIdro Project takes place at the University of Basilicata in cooperation with Fondazione per il Sud; aim of the project is promotion of the employment of 18 young talents (12 environmental engineers and 6 geologist). In the case of study, a geological internship of the duration of 6 months has been carried out at the A.d.B. Destra Sele, with the aim of studying and preventing hydrogeological Risk (Landslides and Floods) within the area of competence, that means the southern portion of the Sorrento Peninsula (Amalfi Coast between Salerno and Punta Campanella), the mountainslopes of the Mountains of Cava and Salerno (Monti Lattari) and the southern slopes of the Picentini Mounts between Salerno and Eboli. Recently the A.d.B. Destra Sele cooperates with the A.d.B. Interregionale Sele and the A.d.B. Della Basilicata. Studying and monitoring of hydrogeological Risk includes geological, geomorphological and hydrogeological approach to debris-and mudflow events internal to the area of competence, as well as to slow-kynematics landslides (flow-like and rotational slides). An example of such a phenomenon is the slow earthflow of San Mango Piemonte, recently studied and reported in this poster. The A.d.B. publishes periodic updates of the “PAI” (Piano di Assetto Idrogeologico), so it is necessary to renew the state of artconcerning the style, status and dimension of the activity of each landslide. Fast-kynematics are typical for debris- and mud flow events, still active along the narrow and steep valleys of the southern Lattari Mounts, in particular the Vallone di Raito and the secundary N-S trending valleys localized between Vietri Sul Mare and Positano. The steep slope and the presence of 1 to 5 meters thick pyroclastic deposits of the Campi Flegrei “Ignimbrite Campana” or “Tufo Grigio” formation and, subsequently, of the 79 A.D. And 1688 eruptions of Mt. Vesuvius, make those furrows and valleys very hazardous in terms of hydrogeological disease. Debris flow and mud flow phenomena are quite common in the studied area; there are no ways to avoid those events, the activityof mapping and monitoring of landslide activity promoted by the A.d.B. is the only measure we can improve and use in the best possible way (this means: respect of the Risk areas signed in the PAI). The experience of a stage within the A.d.B. Destra Sele has been very interesting and constructive, and the aims of ProIdro have been achieved until now.

References

SORECA S. (2011): Monitoring of a slow earth flow at San Mango Piemonte (SA) and mapping of local geomorphological and hydrogeological hazard. Extended abstract and poster session, 1° international workshop on Methods And Technologies For Environmental Monitoring And Modelling: Landslides And Ground Water Dynamics; University of Basilicata, 29.09/03.10 2011.SORECA S. (2011): Dissesto idrogeologico. Quali pericoli corre il Sannio. Il Quaderno (quotidiano di Benevento), 11.11.2011 -http://www.ilquaderno.it/dissesto-idrogeologico-quali-pericoli-corre-sannio--65311.html

THE OROGRAPHIC EFFECTS ON SPATIAL EXTREME RAINFALL VARIABILITY IN CAMPANIA REGION (ITALY)

Pelosi, A.(1); Furcolo, P.(2); Rossi, F.(3); Villani, P.(4)

(1) University of Salerno, Department of Civil Engineering, Fisciano (SA), IT. E-mail: apelosi@unisa.it(2) University of Salerno, Department of Civil Engineering, Fisciano (SA), IT.(3) University of Salerno, Department of Civil Engineering, Fisciano (SA), IT.(4) University of Salerno, Department of Civil Engineering, Fisciano (SA), IT.

In the neighborhood of orographic obstacles, the interaction between atmospheric circulation and topography, especially during intense frontal events, produces a significant amplification of the precipitation driven by the characteristics of the orographic barriers, which in turn enhances spatial rainfall variability in a way that the linear geostatistics techniques fail to capture. A statistical tool for the identification of the spatial non linearity in extreme rainfall from ground measurements is proposed in order to highlight how linear geostatistics is not able to describe the spatial variability of the rain field in areas with a strong orographic forcing. This statistical tool is applied to the mean of the annual maxima of daily rainfall obtained from 605 raingauges placed in Campania and in a convenient surrounding area and it consists in the use of the cross-validation technique, based on linear geostatistics, to calculate the spatial interpolation errors and to find the places in which Ordinary Kriging Predictor gives an “anomalous” under-evaluation of the rainfall field due to the null hypothesis of weak stationarity at the regional scale.The location of these sites, called so “anomalous”, is then compared to topography in order to emphasize the influence of orographic barriers on the precipitation field.The orographic barriers has been defined as reported in the study conducted by Cuomo et al. (2011), which is based on an objective and multi-scalar analysis of geo-morphometric characteristics of the topography. The study provides orographic entities, hierarchically organized in nested orographic classes, among which we have considered groups (IV order) and systems (III order).The results of the comparison are very significant: the anomalous sites are located very close to orographic barriers and about 1/3 of the stations placed in orographic areas are anomalous.Finally, we propose a preliminary model for the regional estimate of the mean of the annual maxima of daily rainfall that gives a better interpretation of the non linearity of the rainfall field in orographic areas. In the model, the mean of the annual maxima of daily rainfall is seen as the product of a basis, weakly stationary process and of an amplification factor. The amplification factor, AF, can be calculated, in each point located in orographic area, through a multiple regression model of three topographic variables related to the orographic entity of affiliation: (i) slope, (ii) prominence and (iii) exposition, which is defined as the cosine of the angle between the dominant direction of the wet air masses and the principal direction of inertia related to the minimum moment of the orographic shapes. The suggested model constitutes an improvement in the regional estimate of the mean of the annual maxima of daily rainfall in Campania, particularly in areas with a strong orographic forcing.

References

Cuomo, A., Guida, D. and Palmieri, V. (2011) Digital orographic map of peninsular and insular Italy, Journal of Maps, v2011, 447-463. 10.4113/jom.2011.1209.

GIS-BASED DEFINITION OF THE MOUNTAINS AS OROGRAPHIC BARRIERS: FROM THE CAMPANIA-LUCANIAN RANGE TO APPENNINE CHAIN (ITALY), TOWARD OROGRAPHY OF EUROPE.

Guida, D.(1); Cestari, A.(2); Cuomo, A.(3); Palmieri, V.(4); Siervo, V.(5);

(1) University of Salerno, Department of Civil Engineering, Fisciano (SA), IT. E-mail: dguida@unisa.it(2) CUGRI, University of Salerno, Fisciano, IT.(3) University of Salerno, Department of Civil Engineering, Fisciano (SA), IT.(4) ARCADIS, Napoli, IT.(5) CUGRI, University of Salerno, Fisciano, IT.

The presence of mountains on the land surfaces plays a central role in the space-space-time dynamics of the hydrological, geomorphic and ecological systems. The poster shows method, procedure and results of the identification, delimitation and classification of the orographic relief in the Campania – Lucanian Apennine (Southern Italy) to investigate the effects of large-scale orographic and small-scale windward-leeward phenomena on distribution, frequency and duration of rainfall. The scale-dependent effects derived from the topographic relief favour the utilization of a hierarchical and multi-scale approach. The approach is based on a GIS procedure applied on Digital Elevation Model (DEM) with 20 meters cell size and derived from Regional Technical Map (CTR) of Campania region (1:5000). The DEM has been smoothed from data spikes and pits and we have then proceed to: a) Identify the three basic landforms of the relief (summit, hillslope and plain) by generalizing a previous 10-type landforms using the TI method and by simplifying the established rules of the differential geometry on topographic surface; b) Delimitate the mountain relief by modifying the method proposed by other authors. It is based on three concepts: prominence , morphological variability and parent-child relationship. Graphical results have shown a good spatial correspondence between the digital definition of mountains and their morpho-tectonic structure derived from tectonic geomorphological studies; c) Classify, by using a set rules of spatial statistics (Cluster analysis) on geomorphometric parameters (elevation, curvature, slope, aspect, relative relief and form factor). Then, we have recognized three prototypal orographic barriers shapes: cone, tableland and ridge, which are fundamental to improve the models of orographic rainfall in the Apennine Chain. Finally, we have performed, extended and GIS-automated the method of Moutain Ordering to Peninsular and Insular Italy, producing an Orographic Informative System, recently published on Journal of Maps.

References

CUOMO, A. and GUIDA, D. (2010a) Definizione Gis based delle barriere orografiche dell'Appennino Campano-Lucano (Italia Meridionale), In XXXII Convegno Nazionale di Idraulica e Costruzioni Idrauliche.CUOMO, A. and GUIDA, D. (2010b) Orographic barriers GIS-based definition of the Campania-Lucanian Apennine Range (Southern Italy), poster Session “Complex System in Geomorphology”,Geophysical Research Abstracts, 12, EGU General Assembly, Vienna.A.CUOMO, D. GUIDA and V.PALMIERI (2011)Digital orographic map of peninsular and insular Italy Journal of Maps, 447-463

PRESENTATION OF DEBRIS-FLOW SUSCEPTIBILITY MODELS BASED ON STATISTICAL LEARNING AND EXTRAPOLATION TO A SPECIFIC DEBRIS-FLOW INDUCED HAZARD: LANDSLIDE TSUNAMI.

Bregoli, F.(1); Chevalier, G.(2); Bateman Pinzon, A.(3)

(1) Barcelona Tech, Sediment Transport Research Group, DEHMA, Barcelona, ES. E-mail: francesco.bregoli@gits.ws(2) Barcelona Tech, Sediment Transport Research Group, DEHMA and Department of Geotechnical Engineering and

Geosciences, Barcelona, ES.(3) Barcelona Tech, Sediment Transport Research Group, DEHMA, Barcelona, ES.

Examples of debris-flow destructive power of erosion have been witnessed in various mountainous environments, including in the Catalan Pyrenees (Portilla et al., 2010). Debris flows are an ideal mixture of water and debris. Material ranging from boulder to silt, possibly incorporating organic matter or other human-made artifacts flows until deposition occurs. Trigger, propagation and deposition mechanisms are complex and occurrence is generally confined to a stream. No rules for its spatial occurrence (susceptibility) exist but susceptibility models are however built. Statistics are a rather common approach. Three classifiers issued from data mining techniques, rather novel in such studies, have proved to reach performances around 70% in the Catalan Pyrenees when are considered fourteen simple fluvio-morphological parameters gathered for 1145 1st-order catchments. The Catalan Pyrenees still exhibits remnants of past glaciations, for instance cirque, U-shaped valley or high mountain lake (Catalan et al., 2006). The interaction of debris flows with mountain lakes or reservoirs , common in the Catalan Pyrenees, can lead to the occurrence of a noteworthy phenomenon called impulse wave. An impulse wave is created when a sufficient quantity of material enters a water body. The momentum of the sliding material is transferred to a mass of water turning into a giant wave able to travel large distances. The impulse-wave phenomenon is also known as landslide tsunami, although scales are not comparable. However the impulse wave’s potential danger is real. Destructive past events have been reported (i.e. Mount Mayuyama, Japan, 1792, 14500 fatalities; the Vajont Dam, Italy, 1963, 2000 fatalities) and the phenomenon takes place everyday in mountainous environments where situation is favorable, at a less destructive scale. Few laboratory researches have been carried out on the physics of this particular wave (Heller and Hager, 2010) and field data only concern the most disastrous and exceptional ones. A way was imagined to determine impulse wave-prone lakes, tackling two aspects of study. 1) The risk faced by communities is low considering the number of occurrences, but it cannot however be ruled out as past dramatic events showed. If a risk assessment of impulse waves due to debris flows is necessitated, this poster can be a guide on how to work out the susceptibility toward this hazard. 2) Little attention has been drawn to the physics of the phenomenon and laboratory setups are scarce but at small scale. Confronting the phenomenon in its environment is primordial when modeling the phenomenon. And tracking hot spots could have advantages like tackling impulse waves at manageable scale where its environment is accounted for, or gathering of direct field data for simulations. Generally magnitude and frequency are closely linked (the bigger, the less often) but in any case the physic changes (a wave generated in a lake would encompass the same inherent general characteristics of recognized impulse waves). We propose here a way to access data related to impulse waves where a close interaction of the phenomenon with its environment is recurrent enough. It could also support the idea of in-situ setups, but study is required to further investigate this possibility.

References

Catalan J., Camarero L., Felip M., et al. (2006) “High mountain lakes: extreme habitats and witnesses of environmental changes” Limnetica, 25(1-2): 551-584.Heller V. and Hager H. (2010) “Impulse product parameter in landslide generated impulse waves.”, J. Waterw., Port, Coastal, Ocean Eng., Vol. 136, No. 3, 145-155.Portilla M, Chevalier G and Hürlimann M (2010) “Description and analysis of the debris flows occurred during 2008 in the Eastern Pyrenees”, Nat. Hazards Earth Syst. Sci., 10, 1635–1645, 2010.

WECPOS – WAVE ENERGY COASTAL PROTECTION OSCILLATING SYSTEM: A NEW SUBMERGED BREAKWATER

Dentale, F.(1); Trezza, C.(2); Donnarumma, G.(3)

(1) MEDUS, Civil Engineering, Salerno, IT. E-mail: fdentale@unisa.it(2) MEDUS, Civil Engineering, Salerno, IT.(3) MEDUS, Civil Engineering, Salerno, IT.

In recent years, the interest in new technologies developing to produce energy with low environmental impact by using renewable sources has grown exponentially all over the world. In this context, the experiences made to derive electricity from the sea (currents, waves, etc.) are of particular interest.At the moment, due to the many existing experiments completed or still in progress, it is quite impossible to explain what has been obtained but it is worth mentioning the EMEC (European Marine Energy Centre), which summarizes the major projects in the world.Another important environmental aspect, also related to the maritime field, is the coastal protection from the sea waves. Even in this field, since many years, the structural and non-structural solutions which can counteract this phenomenon are analyzed, in order to cause the least possible damage to the environment.The studies in development at the University of Salerno are based on these two aspects previously presented. Considering the technologies currently available, a submerged system has been designed by the researchers of the MEDUS , WECPOS (Wave Energy Coastal Protection Oscillating System), to be located on relatively shallow depths, to can be used simultaneously for both electricity generation and for the coastal protection using the oscillating motion of the water particles. The single element constituting the system is realized by a fixed base and three movable panels that can fluctuate with a fixed angle. The waves interact with the panels generating an alternative motion which can be exploited to produce electricity. At the same time, the constraint movement imposed for the rotation of the panels is a barrier to the wave propagation phenomena,triggering the breaking in the downstream part of the device. So the wave energy will be dissipated obtaining a positive effect for the coastal protection.Currently, the efficiency and effectiveness of the system (WECPOS single module) has been studied by using numerical models. Using the FLOW-3D® software it has been possible to evaluate the hydrodynamic interactions that occur between a regular wave, with different height and period characteristics, and the system.For the coastal protection, by estimating some characteristic parameters (zero-moment wave height Hmo, transmission coefficient Kt and the setup/setdown), the behaviour of the WECPOS device has been analyzed for its ability in the wave energy dissipation. While, considering the rotational angle, angular velocity and the hydraulic torque of the individual panel will be possible to estimate the potential energy production by a Matlab/Simulink model.

AN INNOVATIVE NUMERICAL PROCEDURE TO STUDY THE MARITIME STRUCTURES

Dentale, F.(1); Donnarumma, G.(2); Pugliese Carratelli, E.(3)

(1) MEDUS, Civil Engineering, Salerno, IT. E-mail: fdentale@unisa.it(2) MEDUS, Civil Engineering, Salerno, IT.(3) C.U.G.RI., Civil Engineering, Salerno, IT.

The MEDUS is developing an innovative procedure that, by using cad and numerical software, gives the possibility to study with a more detailed approach the hydrodynamic of the wave motion (overtopping, breaking, run-up, reflection, transmission) over a rubble mound structure (emerged or submerged) as well as the hydraulic stability of the armour stones. The simulations are carried out so that the filtration of the fluid within the interstices of a concrete blocks breakwater, is evaluated by integrating the Reynolds Averaged Navier-Stokes equations (RANS/RNG) inside the voids rather than making use of the widespread “porous media" approach. The structure is thus modeled, very much like in the real world or in the physical laboratory testing, by overlapping individual three-dimensional elements (Stones, AccropodeTM, Core-locTM, Xbloc®) and then the computational grid is fitted so as to provide enough computational nodes within the flow paths.Defined the virtual breakwater, the geometric implemented configurations were imported into FLOW-3D® to evaluate the hydrodynamic interactions and the calculation model was made with a numerical channel scheme with an horizontal bottom.In order to have a preliminary validation, the numerical results were compared with empirical literature formulas and with physical data derived from laboratory tests (Zanuttigh and Van der Meer 2006 and Muttray et al 2006). The hydraulic parameters chosen to carry out this validation's procedure were the "run up", the reflection coefficient "Kr" and overtopping flow “Q”.

THE VULNERABILITY OF THE MESSINA PROVINCE: FROM GIAMPILIERI TO SAPONARA

Stancanelli, L.(1); Faraci, C.(2); Foti, E.(3); Musumeci, R.(4); Nicolosi, V.(5)

(1) University of Catania, Department of Civil and Environmental Engineering, Catania, IT. E-mail: cfaraci@unime.it(2) University of Messina, Department of Civil Engineering, Messina, IT.(3) University of Catania, Department of Civil and Environmental Engineering, Catania, IT.(4) University of Catania, Department of Civil and Environmental Engineering, Catania, IT.(5) Sicilian Region, Department of Civil Protection, Messina, IT.

The Messina Province is located in the Northern Eastern part of Sicily Island. It is characterized by the presence of the Peloritani and the Nebrodi Mountains, facing the Tyrrhenian and the Ionian Sea respectively. The geomorphology is characterized by river valleys with large hillslope angles (in the range 30°-60°) and catchment basins of small or moderate extensions (in the range 0.5 km2 -12 km2). Within the entire area the soil is composed by metamorphic material, which is easy to be eroded thus forming debris flows, also because of the semi-arid climate that determines high intensity rainstorms of short duration.During the last three years, the Messina Province has been struck by three different important alluvial events which caused several fatalities and severe economic losses. In the present contribution an analysis of such events has been carried out in order to focus analogies and differences, to the aim of providing contributions to identify possible future proactive strategies against debris flow occurrence.On the October the 1st 2009 a severe rainstorm has struck the South district of the Messina Province. In that case in an areasmaller than 60 km2, more than 600 debris flow events occurred in few hours, which resulted in 37 fatalities and damages to public and private structures; one of the most damaged villages was Giampilieri. Also during February-March 2011 heavy rainstorms hit almost the same area, involving in such a case a wider territory, distributed on both sides of the Ionian and the Tyrrhenian of the Messina coast Several shallow landslides caused damages to transportation and public and private buildings.A more recent event is the one which happened the 22nd of November 2011, when an area more than 400 km2 wide was damaged. The most damaged villages were Barcellona Pozzo di Gotto and Saponara, where 3 fatalities have been encountered. Also in this case several damages to infrastructures have been observed, in particular connected to the traffic transport system, sewage system hydraulic structures, private and public buildings. According to the European Parliament directive 2007/60/CE onthe assessment and management of flood risks, in this work some examples of vulnerability debris flow developed maps are presented, with particular emphasis to the alluvial event of 2009. In particular two different methodological approaches for drafting debris flow vulnerability risk maps have been developed: a speditive approach based on uncertain data collected during the first phase of the emergency and a more sophisticated one validated through a numerical model. The speditive approach takes into account preliminary analysis based on in-site surveys, rough geomorphologic data collection, hydraulic streamflow network studies and effects on infrastructures, leading to a colour-coded risk map. While the sophisticated approach makes use of a two-dimensional commercial model FLO-2D (O’Brien, 2006), which is physically based and takes into account the momentum and energy conservation of flows. The model can be used to predict areas potentially endangered by debris flows. FLO-2D simulations have been run in order to analyze debris flow evolution, during the 1st October event, inside the Giampilieri village (ME), which allow to define and validate the vulnerability risk analysis of the analysed sites.

References

O’Brien, J. D.: FLO-2D user’s manual, Version 2006.01, FLO Engineering,Nutrioso, 2006.

SOME CONSIDERATION ABOUT THE EXTREME RAINFALL IN A MEDITERRANEAN AREA

De Luca, C.(1); Rossi, F.(2); Villani, P.(3)

(1) University of Salerno, Department of Civil Engineering, Fisciano, IT. E-mail: cdeluca@unisa.it(2) University of Salerno, Department of Civil Engineering, Fisciano, IT.(3) University of Salerno, Department of Civil Engineering, Fisciano, IT.

In the time series of annual maximum daily rainfall there are outliers that require great attention, their study is often carried out with a regional analysis.About twenty years ago the National Group for Defence from Hydrogeological Disasters for the Italian rivers developed a regional methodology known as VAPI procedure (Rossi, F. and P. Villani, 1994). This procedure is based on: a) the use of TCEV distribution (Rossi et al., 1984); b) a three levels hierarchical regionalization procedure. The extreme rainfall can't be considered independent and identically distributed variables. The VAPI procedure solves this problem by using the TCEV distribution. It assumes that the individual rainfall can be expressed as a mixture of two exponential components: a) the first describes the ordinary events (more frequent and less severe on average); b) the second describes the extraordinary extremes (more severe and less frequent).In recent years, a new procedure for the regionalization of extreme rainfall has been implementing taking into account their different meteorological structures (De Luca et al., 2010).The baroclinic cyclogenesis process is the dominant meteorological phenomenon in the Mediterranean and generally produces ordinary extremes. The extraordinary events are due to two different components: isolated convective cells and tropical like cyclones, defined as hurricane-like cyclones in the Mediterranean environment. The first component affects areas of small extension then it is relevant only for urban basins. The second component consists of hurricane-like cyclones that have a greater extension and are strongly influenced by the interaction between the atmosphere and the sea.The new approach is based on: a) a procedure for “a priori” identification of meteorological structure of the events. With this procedure, it is possible to identify three homogeneous time series in each site. Each series can be studied separately because it can be considered independent of the others; b) the application of Power Extreme Value (PEV) distribution, a probabilistic model of the annual maxima of a marked Poisson process with marks distributed according to a stretched exponential distribution.With reference to the maximum annual daily rainfall time series of Campania we identified the series of events with barocliniccyclogenesis by removing isolated cells and hurricane-like cyclones events. The results obtained are only preliminary results because the study is in progress for checking it and testing the application to other areas of the Mediterranean regions.

References

Rossi, F. and Villani, P., Regional flood estimation methods, in G. Rossi, N. Harmancioglu e V. Yevjevich (Eds.) Coping with floods, 1994, NATO – ASI N. E257: 135-17.Rossi, F., Fiorentino, M. and Versace, P., Two-Component Extreme Value Distribution for Flood Frequency Analysis, Water Resources Research, 1984, 20 (7): 847-856.De Luca, C., P. Furcolo, F. Rossi, P. Villani and C. Vitolo (2010), Extreme Rainfall in Mediterranean. International Workshop Advances In Statistical Hydrology, May 23-25, 2010 Taormina, Italy

Topic 2:Operational tools for alert systems

DEVELOPMENT OF A DSS TO IMPROVE THE FLOOD CONTROL IN THE SPANISH NATIONAL RIVER AUTHORITIES

Ortiz, E.(1); Guna, V.(2)

(1) Idrologia e Ambiente Srl, Idrologia, Napoli, IT. E-mail: enrique.ortiz@idrologiaeambiente.com(2) HidroGaia S.L., Hidrologia, Valencia, ES.

SAIH (Sistema Automatico de Información Hidrologica) program is managed by The Ministry of Environment. The SAIH is a real time remote control and centralization system for obtaining, storage, processing and displaying hydraulic and meteorological parameters.The Ministry of the Environment is developing a project to introduce new technologies at SAIH Project including the implantation of Decision Support Systems (DSS).The implantation has been based mainly on which the architecture of the System is opened as much as possible (FEWS) for the incorporation of all kind of hydrometeorological data (QPF of NWP, Radar, Eumetsat) as well as the implantation of hydrological and hydraulic models (TOPKAPI, ANN "Neural networks", TETIS, SOBEK, MIKE 11 and others).The goal is to have powerful tools that integrate meteorological and hydrological data and to make forecasts in floodssituations by means of hydrological and hydraulic models.

PROBABILISTIC FLOOD FORECAST WITHIN A TIME HORIZON

Coccia, G.(1); Ortiz, E.(2); Todini, E.(3)

(1) Idrologia e Ambiente Srl, Idrologia, Napoli, IT. E-mail: enrique.ortiz@idrologiaeambiente.com(2) Idrologia e Ambiente Srl, Idrologia, Napoli, IT.(3) Università di Bologna, (2) Dipartimento di Scienze della Terra e Geologico-Ambientali , Bologna, IT.

Recent developments in Predictive Uncertainty (PU) assessment allowed probabilistic forecasts to be part of flood warning systems in terms of the probability of occurrence of a future event. Nonetheless, flood managers are urged to answer questions such as: “what is the probability of occurrence of a flood within the next 12/24 hours?” and “when is flooding expected to occur?”, which are not resolved by the present flood forecasting systems. Until recently probabilistic forecasts were developed to provide the probability of threshold exceedance at a specific lead time, not “within” that specific lead time. From a probabilistic point of view, these forecasts provide important information about the probability of exceedance of a maximum river stage within the forecast lead time. This work aims at presenting and discussing the results of recent developments of the Model Conditional Processor (MCP) within the frame of a Multi-Temporal forecast. This approach has been implemented in order to evaluate a discrete time function representing the variation of cumulative probability of exceeding a river stage during the forecast lead time and the distribution of the time occurrence of the flood peak. The resulting processor is also able to estimate the Multi-Temporal probabilistic information starting from one or more model forecasts. After describing the required modifications to the original MCP version in order to perform the Multi-Temporal probabilistic forecasts, this work shows the results obtained on the Po River in Italy. The Civil Protection of Emilia-Romagna Region provided the forecasts of the operational flood forecasting system model, with a time horizon up to 36 hours in advance. These historical data and the relevant forecasts, available for a period of 9 years, where used to develop the Multi-Temporal probabilistic forecasts and to assess their performances.

References

Coccia, G. and Todini, E.: Recent developments in predictive uncertainty assessment based on the model conditional processor approach, Hydrol. Earth Syst. Sci., 15, 3253-3274, doi:10.5194/hess-15-3253-2011, 2011.Todini, E.: A model conditional processor to assess predictive uncertainty in flood forecasting, Intl. J. River Basin Management, 6 (2), 123-137, 2008.Krzysztofowicz, R.: Probabilistic flood forecast: exact and approximate predictive distributions, Research Paper RK–0802, University of Virginia, September 2008.

NOWCASTING OF OROGRAPHIC RAINFALL BY USING DOPPLER WEATHER RADAR

Panziera, L.(1); Germann, U.(2)

(1) MeteoSvizzera, APSN, Locarno, CH. E-mail: luca.panziera@meteoswiss.ch(2) Meteosvizzera, APSN, Locarno, CH.

A novel approach to the issue of nowcasting orographic precipitation is presented. Since orographic forcing determines a strongrelation between mesoscale flows, air-mass stability and rainfall patterns, these quantities are used as predictors of precipitation in the mountains. In particular, the past situations with the predictors most similar to those observed at the current instant are identified in a large historical data set; the rainfall observed by radar after these similar situations are used to produce the forecast. The system developed at MeteoSwiss, in the context of the IMPRINTS project, is tested in real-time in the Lago Maggiore region in the southern part of the European Alps over 127 days of longlasting and widespread orographic precipitation. A comprehensive evaluation of the heuristic tool is presented.As a further improvement of the system, we plan to include the prediction of intense quasi-stationary cells which often develop over the windward alpine slopes.

FLASH FLOOD FORECASTING USING SIMPLIFIED HYDROLOGICAL MODELS, RADAR RAINFALL FORECASTS AND DATA ASSIMILATION

Smith, P.(1); Panziera, L.(2); Beven, K.(3)

(1) Lancaster Unviersity, Lancaster Environment Centre, Lancaster, GB. E-mail: p.j.smith@lancs.ac.uk(2) MeteoSwiss, , Locarno Monti, CH.(3) Lancaster Univeristy, Lancaster Environment Centre, Lancaster, GB.

The issuing of timely flood alerts may be dependant upon the ability to predict future values of water level or discharge at locations where observations are available. Catchments at risk of flash flooding often have a rapid natural response time, typically less then the forecast lead time desired for issuing alerts. This work focuses on the provision of short-range (up to 6 hours lead time) predictions of discharge in small catchments based on utilising radar forecasts to drive a hydrological model. An example analysis based upon the Verzasca catchment (Ticino, Switzerland) is presented. The techniques used have been developed as partof the IMPRINTS project.Time series models with a mechanistic interpretation (so called Data-Based Mechanistic model) have been shown to provide reliable accurate forecasts in many hydrological situations. In this study such a model is developed to predict the discharge at an observed location from observed precipitation data. The model is shown to capture the snowmelt response at this site. Observeddischarge data is assimilated to improve the forecasts, of up to two hours lead time, that can be generated from observed precipitation.To generate forecasts with greater lead time ensemble precipitation forecasts are utilised. In this study the Nowcasting ORographic precipitation in the Alps (NORA) product is utilised. NORA precipitation forecasts are derived from historical analogues based on the radar field and upper atmospheric conditions. As such, they avoid the need to explicitly model the evolution of the rainfall field through for example Lagrangian diffusion.The uncertainty in the forecasts is represented by characterisation of the joint distribution of the observed discharge, the discharge forecast using the (in operational conditions unknown) future observed precipitation and that forecast utilising the NORA ensembles. Constructing the joint distribution in this way allows the full historic record of data at the site to inform the predictive distribution. It is shown that, in part due to the limited availability of forecasts, the uncertainty in the relationship between the NORA based forecasts and other variates dominated the resulting predictive uncertainty.

References

Smith, P.J., Beven, K., Panziera, L., & Germann, U. (2011) Flash Flood forecasting using Data Based Mechanistic models and radar rainfall forecasts. In: Weather Radar and Hydrology (Proceedings of a symposium held in Exeter, UK, April 2011). IAHS Publ. 351.Panziera L., Germann U., Gabella M. & Mandapaka P.V. (2011) NORA – Nowcasting of Orographic Rainfall by means of Analogues. Q. J. R. Meteorol. Soc., in press.

USE OF “SERIES DISTANCE” FOR IDENTIFICATION OF BEHAVIORAL MEMBERS IN ENSEMBLE FLASH-FLOODS NOWCASTING

Zappa, M.(1); Fundel, F.(2); Liechti, K.(3); Germann, U.(4); Ehret, U.(5)

(1) WSL, Hydrological forecasts, Birmensdorf, CH. E-mail: massimiliano.zappa@wsl.ch(2) WSL, Hydrological forecasts, Birmendsorf, CH.(3) WSL, Hydrological forecasts, Birmensdorf, CH.(4) Meteoswiss, Radar meteorology, Locarno-Monti, CH.(5) Karslruhe Institue for Technology, Hydrology, Karslruhe , CH.

We present an application of the “Series Distance” (SD, Ehret and Zehe, 2011) as metric for confining uncertainty in initial conditions in operational flood forecasts. SD is able to discriminate between timing and amplitude errors seems and also discerns between rising and receding limbs of an event. We use SD for the selection of most “promising” members of a real time ensemble nowcasting chain combining the ensemble radar information REAL (Germann et al., 2009) and the semi-distributed hydrological model PREVAH (Viviroli et al., 2009). Such ensemble includes 25 members and is a run operationally at WSL for the IMPRINTS test-bed Verzasca since 2007 (Liechti et al., 2012).The driving questions for applying SD are: Is it necessary to calculate all 25 possibilities? Can we confine uncertainty? Does picking only the “n” best initial states from the ensemble nowcasting result in better forecasts?We used some of our archived forecasting products for addressing these questions. According to the ranking given by SD we computed the Nash Efficiency and the Root Mean Square Error (RMSE) of all members for each day available in our time series. We split the evaluation into two periods:- Hindcast period, driven by REAL (day-8 to day0)- Forecasting period, driven by the limited area numerical weather prediction model COSMO7 (Day1 and Day2)Both independent verifications with Nash and RMSE point out that the ranking generated with SD is well able to discriminate the best members of our ensemble. In the “Hindcast period”, if one always selects the best SD-member a Nash of 0.81 and a RMSE of 6.2 m3/s are obtained. By always taking the median member (member 13) a Nash of 0.58 and a RMSE of 9.4 m3/s are obtained. The average performance of the top five to seven members is rather similar. This very positive picture is unfortunately not confirmed when the performance of the “Forecasting period” is addressed. While it is true, that members with better SD-rank have better scores than members with worse SD-agreement, this difference in skill during initialization is having few influence on the skill during the period where meteorological forcing is provided by COSMO7. Almost all members have a Nash of around 0.58 and a RMSE of 10-11 m3/s. “Good” initial conditions have a very short “half-life time” in the Verzasca basins. This occurs because often forecasting period purely consists on recession limbs, all starting with very similar conditions.SD is a useful method to sort models, addressing hydrological aspects. Strictly seen no member should be omitted in order to avoid over-confidence of the ensemble. We could demonstrate that the selection of 7 members is fair enough to obtain the maximum skill from a ensemble ranked with SD. This is a worthwhile step in order to confine uncertainty.

References

Ehret, U. and Zehe, E.: Series distance – an intuitive metric to quantify hydrograph similarity in terms of occurrence, amplitude and timing of hydrological events, Hydrol. Earth Syst. Sci., 15, 877-896, doi:10.5194/hess-15-877-2011,Germann, U., Berenguer, M., Sempere-Torres, D. and Zappa, M., 2009. REAL - Ensemble radar precipitation estimation for hydrology in a mountainous region. Quarterly Journal of the Royal Meteorological Society, 135(639): 445-456.Viviroli, D., Zappa, M., Gurtz, J. and Weingartner, R., 2009a. An introduction to the hydrological modelling system PREVAH and its pre- and post-processing-tools. Environmental Modelling & Software, 24(10): 1209-1222.

THE EUROPEAN PRECIPITATION INDEX BASED ON SIMULATED CLIMATOLOGY – PERFORMANCE ASSESSMENT FOR EXTREME RAIN-STORM AND FLASH FLOOD EARLY WARNING IN EUROPE

Alfieri, L.(1); Thielen Del Pozo, J.(2)

(1) European Commission - Joint Research Centre, Institute for Environment and Sustainability, Ispra, IT. E-mail: lorenzo.alfieri@jrc.ec.europa.eu

(2) European Commission - Joint Research Centre, Institute for Environment and Sustainability, Ispra, IT.

Extreme rain-storms are known for triggering devastating flash floods in various regions of Europe and particularly along the Mediterranean coasts. Despite recent notable advances in weather forecasting, most operational early warning systems for extreme rainstorms and flash floods are based on rainfall estimation and measurement, rather than on forecasts. As a result, warning lead times for flash floods are bounded to few hours and warnings are usually issued when the event is already taking place.This work proposes a novel early warning system for heavy precipitation events in Europe, aimed at detecting extreme rainfallaccumulations over short durations and within small-size catchments prone to flash flooding. The system is based on the recently developed European Precipitation Index based on simulated Climatology (EPIC, Alfieri et al., 2011), which is calculated usingCOSMO-LEPS ensemble weather forecasts and subsequently fitted with gamma distributions at each time step of the forecast horizon. Probabilistic exceedance of warning thresholds is calculated and alert points are generated whereas potentially extreme events are detected. Daily forecasts of EPIC over 22 months ending in September 2011 were compared with observed rain-storm events and flash floods occurred in Europe. Results denote a probability up to 90% of detecting extreme events, corresponding to 45 events correctly predicted with average lead time of 32 hours.

References

Alfieri L., Velasco D., Thielen J., 2011. Flash flood detection through a multi-stage probabilistic warning system for heavy precipitation events. Advances in Geosciences, 29: 69–75, doi:10.5194/adgeo-29-69-2011.

DEVELOPMENT OF AN OPERATIONAL FLOOD WARNING SYSTEM IN THE GUADALHORCE BASIN (ANDALUCIA, SPAIN): FIRST RESULTS AND POSSIBLE CONNECTION WITH THE EUROPEAN FLOOD ALERT SYSTEM (EFAS)

Versini, P.(1); Santiago-Gahete, A.(2); Sempere-Torres, D.(3)

(1) UPC, CRAHI, Barcelona, ES. E-mail: pierre-antoine.versini@crahi.upc.edu(2) Junta de Andalucía, AMAYA, Sevilla, ES.(3) UPC, CRAHI, Barcelona, ES.

The Guadalhorce basin is located in Andalusia (Southern Spain). Torrential floods are historically significant and represent an important risk for the city of Malaga. In 2008, EGMASA, who was in charge of flood risk management in the area, decided to implement an operational flood warning system (FWS) with the aim of minimising the risk to people, and economic activity, as well as for guiding water resources management. The FWS system is oriented to provide distributed warnings based on rainfall accumulations and discharge forecasts. Rainfall accumulation maps are generated according to the interpolation of rain gauge measurements and available weather radar rainfall fields, whereas discharge forecasts are computed using a distributed rainfall-runoff model. Due to the lack of flow measurements data, the model was calibrated a priori in most of the basin area. The objective of the present work is to describe and analyse the efficiency of the implemented FWS. The performance of the system has been tested on two recent events (early 2010), which caused many inundations at the Guadalhorce main river and tributaries. First results show how the warning system performed significantly well and was able to forecast the location and timing of flooding. The validation analysis demonstrates that a simplified hydrological model and a rough calibration performs good enough to issue valuable warnings. Moreover, the available European Flood Alert System (EFAS) flood forecasts have been used to prevent from the flood several days in advance. Despite its low spatial and temporal resolution, EFAS is though to be agood complement tool to improve flood forecasting since the 72 hours leadtime forecasts usefully complement the short lead times of radar-based FWS.

PORTABILITY OF A REALTIME FLOOD FORECASTING SYSTEM

Schmid, M.(1); Liechti, K.(2); Zappa, M.(3); Fundel, F.(4)

(1) WSL, Hydrological forecasts, Birmensdorf, CH. E-mail: massimiliano.zappa@wsl.ch(2) WSL, Hydrological forecasts, Birmendsorf, CH.(3) WSL, Hydrological forecasts, Birmensdorf, CH.(4) WSL, Hydrological forecasts, Birmensdorf, CH.

Flood forecasting systems can help to mitigate the effects of floods. Not always there is observed data available to calibrate aflood forecasting system and therefore it would be useful if a calibrated model could be transferred to poorly gauged catchments.In this study we investigate the portability of a real-time flood forecasting system from the Swiss Alps to other, mediterranean catchments. The semi-distributed hydrological model system PREVAH used in this study is forced by precipitation forecasts from the Consortium for small Scale Modeling Limited Area Ensemble Prediction System (COSMO-LEPS).Climatologies of the model are computed, using a 20 yr long set of COSMO-LEPS reforecasts which are then used to define different initial conditions. The PREVAH model is calibrated for the Verzasca and the Linth-Mollis basin in Switzerland and applied to the Llobregat (Spain) and the Gardon d’Anduze (France) basin. With probabilistic measures of skill, the performance of the runoff forecasts is assessed for the time period 6.5.2010-31.12.2010. As observed and simulated runoff are independent in this study, evaluating portability relies on return periods. In order to give authorities the possibility to improve the management of FF risks a warning tool is developed. In an intuitive way it should have the possibility to represent the levels of possible danger.The results show, that calibrated models could not accurately simulate high discharges if they were transferred to other catchments. But the validation period in this study is rather short and rare times extreme events with high discharge occurred. Thus, in a next step the period should be enlarged and other calibrations could be used. The developed warning tool provides good information if it’s applied to the catchments the model is calibrated on, but transferred to the other basins the probability of correctly detecting floods is low and the ratio of false alarms is high.

Topic 3:Best strategies for

hydrogeological risk mitigation

CHECK DAMS AS MITIGATION APPROACH FOR REDUCING DEBRIS FLOW AMPLIFICATION

Rossi, F.(1); Genovese, M.(2); Viccione, G.(3); Bovolin, V.(4)

(1) University of Salerno, Civil Engineering, Fisciano, IT. E-mail: gviccion@unisa.it(2) University of Salerno, Civil Engineering, Fisciano, IT.(3) University of Salerno, Civil Engineering, Fisciano, IT.(4) University of Saerno, Civil Engineering, Fisciano, IT.

It is proved that a small liquid stream or a triggered landslide may occasionally evolve into a debris flow. As its propagation takes place, available sediments from the bottom slope and nearby banks can be added. In addition, under certain conditions, the entrainment yields an increase of both mass and momentum, enhancing the efficiency of the resulting movement. The same efficiency can be as well sustained by bed liquefaction and mass fluidification. The first is due to an abruptly increase of fluid pore pressure of the bed when overridden, causing a falling of effective shear stresses and therefore behaving like a liquid, the latter consists of the dynamic interaction between sediments and fluid porosity inside the propagating mass, responsible of both high pore pressures and continuous modification of voids and matrix distribution.The amplification process is therefore essential for a proper hazard assessment. For example, average volumes mobilized duringthe 1998 events of Sarno (Italy), have been three times the initial detached volumes.The work here presented means to analyze debris flow amplification features, from the first stages up to the entrainment processes As main result, we obtain that reducing bed slope decreases the amplification to the point it is negligible. This is due to the fact that both bed liquefaction and mass fluidification are attenuated.A mitigation intervention consisting of a check dam system causes a reduction of the original bed slope, determining debris flow volumes to be stored and a stabilization of the banks at the same time. Other mitigation strategies, consisting of open dams and storing reservoirs, do not act likely, hence sustaining the effect of mass amplified.As a check dam system is realized, the slope decreases over time since sediments mobilized by small floods fill on upstream the single dam, eventually reaching the final design slope.The allocation of a check dam system, needed to decrease the amplification process, is not random but related to the position of the areas of triggering formation. Such areas are concentrated along the upstream impluvium heads, named Zero Order Basin (ZOB). We propose a one-dimentional numerical model based on a finite difference scheme. The ruling equations implemented are taken from (Egashira et al., 2000), accounting for erodible beds. Results show that exists a relationship between the original bed slopes and the amount of added volumes. Moreover, varying the different input parameters a particular temporal and spatial evolution of both debris flow and erodible bed is presented. Other numerical analyses have been carried out in (Viccione and Bovolin, 2010; 2011).Concluding, check dam systems with attained design slope of 10-15%, from up to 30-35% exhibits the following advantages:-yield an efficient system control of debris flows;-help reducing liquefaction and fluidization processes;-they are economically affordable.

References

Egashira S, Honda N, Itoh T. 2000. Experimental study on bed material entrainment into debris-flow. In Proceedings of the 2nd International Conference on Debris-flow Hazard Mitigation: Mechanics, Prediction and Assessment, Taipei, Taiwan, August 16–18, 2000 , Wieczorek GF, Naeser ND (eds). Balkema: Rotterdam; 345–350.Viccione G, Bovolin V. 2010. Simulating flash floods with SPH,. International workshop on EU Flood directive implementation in Mediterranean zone: Tools and challenges for efficient risk management. Barcelona (Spain)..Viccione G, Bovolin V. 2011. Simulating triggering and evolution of Debris-Flows with SPH. 5th International Conference on Debris-Flow Hazards Mitigation. Padua (Italy).

FLOODS IN ITALY: IF DEFENCE WORKS ARE PART OF THE PROBLEM, CAN RIVER RESTORATION BE A SOLUTION?

Trentini, G.(1); Monaci M.(2); Gusmaroli G.(3); Goltara A.(4); Pavan S.(5); Varese P.(6); Ciervo F.(7)

(1) CIRF - Centro Italiano per la Riqualificazione Fluviale, Technical Secretariat, Mestre, IT. E-mail: g.trentini@cirf.org

(2) CIRF - Centro Italiano per la Riqualificazione Fluviale, Technical Secretariat, Mestre, IT.(3) CIRF - Centro Italiano per la Riqualificazione Fluviale, Technical Secretariat, Mestre, IT.(4) CIRF - Centro Italiano per la Riqualificazione Fluviale, Technical Secretariat, Mestre, IT.(5) CIRF - Centro Italiano per la Riqualificazione Fluviale, Technical Secretariat, Mestre, IT.(6) CIRF - Centro Italiano per la Riqualificazione Fluviale, Technical Secretariat, Mestre, IT.(7) Civil Engineering Department, University of Salerno, Fisciano (SA), IT.

A large number of floods have occurred in Italy during the last decades, causing dozens of casualties and hundreds of millions of Euros damage. Usually, these are described as “natural disasters” by most of the public opinion, decision-makers and practitioners. However, little attention is put on how land development and defence works themselves can alter the hydromorphological behaviour of rivers and catchments , sharpening and increasing the magnitude of flood events.Our thesis is that in several cases the planning and implementation of flood defence schemes has followed a very narrow and local approach, mainly conditioned by the goal of maximizing the extension of productive land uses (e.g. agriculture, urban and industrial settlements), while overall benefits at larger temporal and spatial scales have been neglected. The consequent narrowing of stream corridors, with loss of floodplain and erodible areas, has led to geomorphological instability, exacerbation of flood risk downstream and sometimes even locally, rising cost for replacement and maintenance of defence works, decreasing landscape resilience. In other words, instead of a solution, the traditional flood defence approach has often become part of the problem. If this is true, conversely, river restoration –advocating, among other things, to give back more room to the river, whenever possible, restoring its erodible corridors and floodplain– is not only a way to improve the ecological status, but it can be the best choice to manage flood risk in a cost-effective way.At the end of 2011, CIRF (Italian Centre for River Restoration) started a self-funded research aimed at verifying this thesis, through an ex-post analysis of some significant flood events.The main topics of interest are the following: analysis of the social perception of flood risk and its influence on decision-makers and planners concerning the management approach of watersheds and rivers; analysis of past urban development trends within the river corridors, including how this has influenced rivers hydrological and geomorphological features and its influence on the current flood risk conditions; assessment of the main features of present vegetation and sediment management procedures, including their influence on the magnitude of flood events; comparison between the stakeholders, practitioners and decision-makers perception of this influence and what is reported in the scientific literature.This work does not aim to lead to ultimate and quantitative results, its goal is rather to identify: key issues that should be explored in further research; food for thought about the definition of a new approach to river management and land use planning, able to face all real causes of flood risk, and to integrate the goals of the Floods Directive (2007/60/EC) with those of the Water Framework Directive (2000/60/EC).To date the research is focusing on six flood events, some related to flash flood and debris flow:Piedmont region, 2000, flood; Piedmont region, 2008 debris flow and flood; Messina, Sicily, 2009, debris flow; Atrani, Amalfi coast, Campania, 2010, flash flood; Veneto region, 2010, flood; Cinque Terre and Val di Vara, Toscana and Liguria regions, 2011, flood.An overview of the case studies and some first results are presented.

References

CIRF, 2006. La riqualificazione fluviale in Italia. Linee guida, strumenti ed esperienze per gestire i corsi d'acqua e il territorio. A. Nardini, G. Sansoni (curatori) e coll., Mazzanti editore, Mestre (VE), Italy.Sansoni G., 2011. Magra, Vara, Cinque Terre: dal disastro alla futura gestione del territorio. Personal Communication, Sarzana (SP), Italy.

PREDICTING THE RIVER MORPHOLOGY AFTER RIVER RESTORATION. THE METHODOLOGY VALURI

Nardini, A.(1); Pavan, S.(2)

(1) CIRF - Centro Italiano per la Riqualificazione Fluviale, Technical Secretariat, Venezia, IT. E-mail: s.pavan@cirf.org(2) CIRF - Centro Italiano per la Riqualificazione Fluviale, Technical Secretariat, Venezia, IT.

This work proposes a tool which can enable river managers to ascertain whether the key idea of River Restoration is valid, i.e. that rivers in more natural status are desirable not only for pure environmental reasons, but also to combat flood and geomorphic risk. The point addressed is how to predict the morphology and geometry that a river will assume after the application of a River Restoration project which foresees significant changes in the system of defence and exploitation works, as well as morphological adjustments. To this aim, a semi-quantitative methodology that integrates several differing criteria has been developed. These criteria include historical analysis of geomorphic evolution, expert-based mechanistic reasoning, checking with empirical qualitative formulas and analytical support from fluvial geomorphology and classic hydraulics. The development of the methodology has taken place on a case study along the 80 km of Chiese River, downstream of Idro lake, in Northern Italy. Most of the river runs in a semirural area, touching several small towns and rural settlements. Almost all of its course is highly artificialized with several big size weirs, semi-continuous longitudinal defences, and big levees.For this river, the River Po Basin Authority (AdBPo) had developed a feasibility study (SdF) to define the proper hydraulic setting to combat flood risk.We wanted to investigate whether a different solution, with much less concrete in the river, could imply significant economical savings in terms of works not implemented and/or operation, maintenance and replacement costs avoided, while the risk increase could be kept sufficiently low, and the ecological status improved (Nardini and Pavan, 2012b).The VALURI methodology starts considering a set of alternative river settings. For each of them, an initial new set of flood defences and exploitation works is defined together with a possibly modified initial morphology as a consequence, for instance, of weirs removal, levees dismantling, or renewed connection between channel and previous floodplain.In correspondence with each alternative, a new dynamic equilibrium is assumed to establish, soon or later. The posed problem is hence to predict the future equilibrium morphology for each alternative. Defined alternatives are all based on the existing setting and the setting foreseen according to River Po Basin Managament plans. They are: ALT_0: the “quasi business-as-usual” alternative, which implies high OMR costs for keeping the current defence and exploitation works system; ALT_SdF: which represents the solution proposed by AdBPo which basically espouses the criterion of putting the river corridor in safe conditions with respect to the 200 years recurrence time TR flood. including some interventions of partial restoration, mainly afforestation of river corridor and removal of obsolete defences, but also several new defences or adjustments of existing ones; ALT_Base: this is a first step of restoration which implements the criterion of eliminating as much as possible concrete works, while keeping the impact on the anthropogenic system as low as possible (CIRF, 2006).The VALURI application to river Chiese has to be considered as a pilot case study, since the methodology was conceived and developed during this application. Nevertheless, the methodology developed for Chiese River is of quite general validity and offers a path for similar applications to a wide class of water streams (Nardini and Pavan, 2012a).

References

CIRF, 2006. La riqualificazione fluviale in Italia. Linee guida, strumenti ed esperienze per gestire i corsi d'acqua e il territorio. A. Nardini, G. Sansoni (curatori) e coll., Mazzanti editore, Mestre.Nardini A. and Pavan S., 2012b. River restoration: not only for the sake of nature, but also for saving money while addressing flood risk. A decision making framework applied to the Chiese River (Po basin-Italy), Journal of Flood Risk Management, DOI: 10.1111/j.1753-318X.2011.01132.xNardini A. and Pavan S., 2012a. What river morphology after restoration? The methodology VALURIJournal of River Basin Management, DOI:10.1080/15715124.2011.640637

URBAN WATERSHED RESTORATION AS A STRATEGY TO FACE FLASH FLOODS IN PORT-AU-PRINCE, HAITI

Trentini, G.(1); Bresciani, R.(2); Mastropaolo S.(3)

(1) CIRF - Centro Italiano per la Riqualificazione Fluviale, Technical Secretariat, Mestre, IT. E-mail: g.trentini@cirf.org

(2) Iridra s.r.l., Firenze, IT.(3) Palermo, IT.

The urban low-lying area of south–west Port–au–Prince, Haiti, is affected by dramatic flash floods, causing several casualties and serious damage. The problem is increasing year by year.In 2011 the United Nation Environmental Programme (UNEP) and the United Nation Office for the Project Services (UNOPS) commissioned CIRF a study aiming at the identification of a strategy of intervention able to link the reduction of flood risk to the improvement of life conditions for inhabitants as well as the ecological status of the streams network and natural areas.The studied area is 20 sq km wide and subdivided in 7 catchments. It extends from the ridge of Morne l'Hopital, having a maximum elevation of 1,033 m a.s.l., to the sea shore. The maximum distance between the ridge and the shore is about 4 km andconsequently the mountainsides and streams courses are very steep.Wastewater and municipal solid waste are poorly managed. Ravines (small and steep streams, almost ephemeral) are affected bya widespread presence of defence works, houses built very close to or into the stream bed and, severe alteration due to reclamation works by the seaside. The extensive deforestation in the upper rural watershed, together with the heavy urbanization of the lower part led to a marked sharpening of hydrological response.This situation is the result of a dramatic, unplanned and informal expansion of urban settlements that have taken place in the area since the early 1980s. The 12 January 2010 earthquake has worsened a situation that was already very critical.The CIRF's approach to river restoration was applied and adapted to the Port-au-Prince context. The main lines of action within the proposed strategy are the following: establishment of a tenable limit for maximum urban expansion; creation of continuous“green” corridors along ravines to convey stormwater, providing room for the natural geomorphological dynamics, riparian vegetation and other services for the community, such as public parks; joint use of retention basins, sustainable urban drainage systems (SUDS) and ecological sanitation techniques to prevent water pollution and mitigate the effect of impervious cover; establishment of soil conservation practices and agroforestry, reforestation of those areas which are unsuitable for agriculture.The study led to outline an Integrated Participatory Watershed Plan, structured in a watershed restoration program and a urban regeneration program, both to be implemented through a participatory process.Watershed restoration provides to urban regeneration a comprehensive strategy for sustainable flood risk mitigation, ravines management, sustainable sanitation and tools to strengthen socio–economical, ecological and environmental links between the urban area and communities and the countryside. Whereas urban regeneration helps watershed restoration in maximizing the penetration of sustainable sanitation and urban runoff reduction measures and in achieving social acceptance for stream corridor restoration, giving new attractive accommodation to households that have to be relocated and reorganizing the urban texture along restored ravines.

References

CIRF, 2006. La riqualificazione fluviale in Italia. Linee guida, strumenti ed esperienze per gestire i corsi d'acqua e il territorio. A. Nardini, G. Sansoni (curatori) e coll., Mazzanti editore, Mestre.Trentini G., Bresciani R. and Mastropaolo S., 2011. Urban Watershed Restoration in Port–au–Prince, Haiti: Strategies for integrated management and intervention. Internal Report, United Nation Environment Programme Disasters and Conflicts Haiti Operation Center, Port-au-Prince.

APPLICABILITY OF THE FUNCTIONAL MOBILITY AREA CONCEPT FOR THEMANAGEMENT OF WATERCOURSES IN THE AUTORITÀ DI BACINO INDESTRA SELE AREA

Affinita, M.(1); Colella, L.(2); D'onofrio, G.(3); Fariello, L.(4); Grimaldi, G.(5); Iannella, S.(6); Lombardi, G.(7); Minotta, C.(8);Moretta, F.(9)

(1) Regione Campania, Autorità di Bacino in Destra Sele, Napoli, IT. E-mail: sergio.iannella@abds.it(2) Regione Campania, Autorità di Bacino in Destra Sele, Napoli, IT.(3) Regione Campania, Autorità di Bacino in Destra Sele, Napoli, IT.(4) Regione Campania, Autorità di Bacino in Destra Sele, Napoli, IT.(5) Regione Campania, Autorità di Bacino in Destra Sele, Napoli, IT.(6) Regione Campania, Autorità di Bacino in Destra Sele, Napoli, IT.(7) Regione Campania, Autorità di Bacino in Destra Sele, Napoli, IT.(8) Regione Campania, Autorità di Bacino in Destra Sele, Napoli, IT.(9) Regione Campania, Autorità di Bacino in Destra Sele, Napoli, IT.

The risk faced by the perifluvial territories does not derive exclusively from the floods but also from the mobility of riverbeds and erosion of the banks, which may lead to the destruction of agricultural areas, facilities and settlements. These mobility processes are not necessarily attributable to a conditions of instability and disequilibrium of the river because, in general, they are the expression of the dynamics of the river which is a dynamic system evolving.As part of the recent activities of the update of P.A.I. (Hydrogeological Basin Plan) by Autorità di Bacino in Destra Sele, a study sample was conducted on a reach of river 3 km length, along the Torrente Prepezzano, a tributary of Fiune Picentino, adding tothe PAI a new perspective based on a dynamic view of the hydrographic network, in which the risk and costs for the reduction of the effects related to its dynamics can be limited by "giving space to the river" defining and separating the several uses of the territory with a careful planning.Generally, Hydrogeological Basin Plans return a static view of river networks and do not cover this kind of phenomena, thus failing a cognitive tool to assess the interactions between the human use of land (which tends to restrain the river) and planimetric evolution of streambed.Through this study, pending subsequent updates of the Plans and the establishment of a Basin Management Plan, finalized to integrate risk reduction with increasing ecological status of rivers (as required by the 2000/60/EC Water Frame Directive and 2007/60/EC Floods Directive), in addition to the classical perimeter flood hazard, we have a "geomorphological hazards", resulting from the mobility of riverbeds, implementing the aspects of fluvial geomorphology in the flood risk assessment.The study focused on field surveys, comparative analysis of time series of aerial photographs (it was used aerial photographs of the river in 1955, 1974, 1990, 2007, defining the range of distraction as the outer envelope of its traces) and on geomorphologic survey of the river corridor, has exclusively a demonstrative meaning, lacking such basic analysis: study of the evolution of the land uses in the basin, sediment balance, any actions with impacts on the equilibrium (eg: removal of sediments from theriverbed), estimation of rates of retreat of the banks.The results obtained had a great value because they allows to elaborate a proposal for delimitation of the flood and geomorphological hazard including the definition of a Functional Mobility Area.

References

MALAVOI J.R., BRAVARD J.P., PIEGAY H., HEROIN E. & RAMEZ P. (1998) – Determination de l’espace de liberte des cours d’eau.AUTORITÀ DI BACINO REGIONALE DESTRA SELE, (2011) - Piano per l'assetto idrogeologico, Sezione Attività pilota sulla perimetrazione della “Fascia di Mobilità Funzionale” lungo il tratto di asta fluviale campione - Studi, rilievi e elaborazioni: Ing. M. Papa & GEORES, Studio associato di geologia di A. Carbone e A. Gallo.

EU directiveDIRECTIVE 2007/60/EC on the assessment and

management of flood risks

DIRECTIVES

DIRECTIVE 2007/60/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL

of 23 October 2007

on the assessment and management of flood risks

(Text with EEA relevance)

THE EUROPEAN PARLIAMENT AND THE COUNCIL OF THEEUROPEAN UNION,

Having regard to the Treaty establishing the EuropeanCommunity, and in particular Article 175(1) thereof,

Having regard to the proposal from the Commission,

Having regard to the Opinion of the European Economic andSocial Committee (1),

Acting in accordance with the procedure laid down in Article251 of the Treaty (2),

Whereas:

(1) Floods have the potential to cause fatalities, displacementof people and damage to the environment, to severelycompromise economic development and to underminethe economic activities of the Community.

(2) Floods are natural phenomena which cannot beprevented. However, some human activities (such asincreasing human settlements and economic assets infloodplains and the reduction of the natural waterretention by land use) and climate change contribute toan increase in the likelihood and adverse impacts of floodevents.

(3) It is feasible and desirable to reduce the risk of adverseconsequences, especially for human health and life, theenvironment, cultural heritage, economic activity andinfrastructure associated with floods. However, measuresto reduce these risks should, as far as possible, be

coordinated throughout a river basin if they are to beeffective.

(4) Directive 2000/60/EC of the European Parliament and ofthe Council of 23 October 2000 establishing aframework for Community action in the field of waterpolicy (3) requires river basin management plans to bedeveloped for each river basin district in order toachieve good ecological and chemical status, and it willcontribute to mitigating the effects of floods. However,reducing the risk of floods is not one of the principalobjectives of that Directive, nor does it take into accountthe future changes in the risk of flooding as a result ofclimate change.

(5) The Commission Communication of 12 July 2004 to theEuropean Parliament, the Council, the EuropeanEconomic and Social Committee and the Committee ofthe Regions ‘Flood risk management — Floodprevention, protection and mitigation’ sets out itsanalysis and approach to managing flood risks atCommunity level, and states that concerted and coor-dinated action at Community level would bring consid-erable added value and improve the overall level of floodprotection.

(6) Effective flood prevention and mitigation requires, inaddition to coordination between Member States, coop-eration with third countries. This is in line with Directive2000/60/EC and international principles of flood riskmanagement as developed notably under the UnitedNations Convention on the protection and use of trans-boundary water courses and international lakes, approvedby Council Decision 95/308/EC (4), and any succeedingagreements on its application.

(7) Council Decision 2001/792/EC, Euratom of 23 October2001 establishing a Community mechanism to facilitatereinforced cooperation in civil protection assistance inter-ventions (5) mobilises support and assistance fromMember States in the event of major emergencies,including floods. Civil protection can provide adequateresponse to affected populations and improve prepa-redness and resilience.

EN6.11.2007 Official Journal of the European Union L 288/27

(1) OJ C 195, 18.8.2006, p. 37.(2) Opinion of the European Parliament of 13 June 2006 (OJ C 300 E,

9.12.2006, p. 123). Council Common Position of 23 November2006 (OJ C 311 E, 19.12.2006, p. 10) and Position ofthe European Parliament of 25 April 2007. Council Decision of18 September 2007.

(3) OJ L 327, 22.12.2000, p. 1. Directive as amended by DecisionNo 2455/2001/EC (OJ L 331, 15.12.2001, p. 1).

(4) OJ L 186, 5.8.1995, p. 42.(5) OJ L 297, 15.11.2001, p. 7.

(8) Under Council Regulation (EC) No 2012/2002 of 11November 2002 establishing the European Union Soli-darity Fund (1) it is possible to grant rapid financialassistance in the event of a major disaster to help thepeople, natural zones, regions and countries concernedto return to conditions that are as normal as possible.However the Fund may only intervene for emergencyoperations, and not for the phases preceding anemergency.

(9) In developing policies referring to water and land usesMember States and the Community should consider thepotential impacts that such policies might have on floodrisks and the management of flood risks.

(10) Throughout the Community different types of floodsoccur, such as river floods, flash floods, urban floodsand floods from the sea in coastal areas. The damagecaused by flood events may also vary across thecountries and regions of the Community. Hence,objectives regarding the management of flood risksshould be determined by the Member States themselvesand should be based on local and regional circumstances.

(11) Flood risks in certain areas within the Community couldbe considered not to be significant, for example in thinlypopulated or unpopulated areas or in areas with limitedeconomic assets or ecological value. In each river basindistrict or unit of management the flood risks and needfor further action — such as the evaluation of floodmitigation potential — should be assessed.

(12) In order to have available an effective tool for infor-mation, as well as a valuable basis for priority settingand further technical, financial and political decisionsregarding flood risk management, it is necessary toprovide for the establishing of flood hazard maps andflood risk maps showing the potential adverse conse-quences associated with different flood scenarios,including information on potential sources of environ-mental pollution as a consequence of floods. In thiscontext, Member States should assess activities thathave the effect of increasing flood risks.

(13) With a view to avoiding and reducing the adverseimpacts of floods in the area concerned it is appropriateto provide for flood risk management plans. The causesand consequences of flood events vary across thecountries and regions of the Community. Flood riskmanagement plans should therefore take into account

the particular characteristics of the areas they cover andprovide for tailored solutions according to the needs andpriorities of those areas, whilst ensuring relevant coordi-nation within river basin districts and promoting theachievement of environmental objectives laid down inCommunity legislation. In particular, Member Statesshould refrain from taking measures or engaging inactions which significantly increase the risk of floodingin other Member States, unless these measures have beencoordinated and an agreed solution has been foundamong the Member States concerned.

(14) Flood risk management plans should focus onprevention, protection and preparedness. With a viewto giving rivers more space, they should considerwhere possible the maintenance and/or restoration offloodplains, as well as measures to prevent and reducedamage to human health, the environment, culturalheritage and economic activity. The elements of floodrisk management plans should be periodically reviewedand if necessary updated, taking into account the likelyimpacts of climate change on the occurrence of floods.

(15) The solidarity principle is very important in the contextof flood risk management. In the light of it MemberStates should be encouraged to seek a fair sharing ofresponsibilities, when measures are jointly decided forthe common benefit, as regards flood risk managementalong water courses.

(16) To prevent duplication of work, Member States shouldbe entitled to use existing preliminary flood riskassessments, flood hazard and risk maps and flood riskmanagement plans for the purposes of achieving theobjectives and satisfying the requirements of thisDirective.

(17) Development of river basin management plans underDirective 2000/60/EC and of flood risk managementplans under this Directive are elements of integratedriver basin management. The two processes shouldtherefore use the mutual potential for commonsynergies and benefits, having regard to the environ-mental objectives of Directive 2000/60/EC, ensuring effi-ciency and wise use of resources while recognising thatthe competent authorities and management units mightbe different under this Directive and Directive2000/60/EC.

(18) Member States should base their assessments, maps andplans on appropriate ‘best practice’ and ‘best availabletechnologies’ not entailing excessive costs in the fieldof flood risk management.

ENL 288/28 Official Journal of the European Union 6.11.2007

(1) OJ L 311, 14.11.2002, p. 3.

(19) In cases of multi-purpose use of bodies of water fordifferent forms of sustainable human activities (e.g.flood risk management, ecology, inland navigation orhydropower) and the impacts of such use on thebodies of water, Directive 2000/60/EC provides for aclear and transparent process for addressing such usesand impacts, including possible exemptions from theobjectives of ‘good status’ or of ‘non-deterioration’ inArticle 4 thereof. Directive 2000/60/EC provides forcost recovery in Article 9.

(20) The measures necessary for the implementation of thisDirective should be adopted in accordance with CouncilDecision 1999/468/EC of 28 June 1999 laying down theprocedures for the exercise of implementing powersconferred on the Commission (1).

(21) In particular, the Commission should be empowered toadapt the Annex to scientific and technical progress.Since those measures are of general scope and aredesigned to amend non-essential elements of thisDirective, they must be adopted in accordance with theregulatory procedure with scrutiny provided for in Article5a of Decision 1999/468/EC.

(22) This Directive respects the fundamental rights andobserves the principles recognised in particular by theCharter of Fundamental Rights of the European Union.In particular, it seeks to promote the integration intoCommunity policies of a high level of environmentalprotection in accordance with the principle of sustainabledevelopment as laid down in Article 37 of the Charter ofFundamental Rights of the European Union.

(23) Since the objective of this Directive, namely the estab-lishment of a framework for measures to reduce the risksof flood damage, cannot be sufficiently achieved by theMember States and can by reason of scale and effects ofactions be better achieved at Community level, theCommunity may adopt measures, in accordance withthe principle of subsidiarity as set out in Article 5 ofthe Treaty. In accordance with the principle of propor-tionality, as set out in that Article, this Directive does notgo beyond what is necessary in order to achieve thatobjective.

(24) In accordance with the principles of proportionality andsubsidiarity and the Protocol on the application of theprinciples of subsidiarity and proportionality attached tothe Treaty, and in view of existing capabilities of MemberStates, considerable flexibility should be left to the local

and regional levels, in particular as regards organisationand responsibility of authorities.

(25) In accordance with point 34 of the InterinstitutionalAgreement on better law-making (2), Member States areencouraged to draw up, for themselves and in the interestof the Community, their own tables illustrating, as far aspossible, the correlation between this Directive and thetransposition measures, and to make them public,

HAVE ADOPTED THIS DIRECTIVE:

CHAPTER I

GENERAL PROVISIONS

Article 1

The purpose of this Directive is to establish a framework for theassessment and management of flood risks, aiming at thereduction of the adverse consequences for human health, theenvironment, cultural heritage and economic activity associatedwith floods in the Community.

Article 2

For the purpose of this Directive, in addition to the definitionsof ‘river’, ‘river basin’, ‘sub-basin’ and ‘river basin district’ as setout in Article 2 of Directive 2000/60/EC, the following defi-nitions shall apply:

1. ‘flood’ means the temporary covering by water of land notnormally covered by water. This shall include floods fromrivers, mountain torrents, Mediterranean ephemeral watercourses, and floods from the sea in coastal areas, and mayexclude floods from sewerage systems;

2. ‘flood risk’ means the combination of the probability of aflood event and of the potential adverse consequences forhuman health, the environment, cultural heritage andeconomic activity associated with a flood event.

Article 3

1. For the purposes of this Directive Member States shallmake use of the arrangements made under Article 3(1), (2),(3), (5) and (6) of Directive 2000/60/EC.

2. However, for the implementation of this Directive,Member States may:

(a) appoint competent authorities different from those iden-tified pursuant to Article 3(2) of Directive 2000/60/EC;

(b) identify certain coastal areas or individual river basins andassign them to a unit of management different from thoseassigned pursuant to Article 3(1) of Directive 2000/60/EC.

EN6.11.2007 Official Journal of the European Union L 288/29

(1) OJ L 184, 17.7.1999, p. 23. Decision as amended by Decision2006/512/EC (OJ L 200, 22.7.2006, p. 11). (2) OJ C 321, 31.12.2003, p. 1.

In these cases, Member States shall, by 26 May 2010, commu-nicate to the Commission the information referred to in AnnexI to Directive 2000/60/EC. For this purpose, any reference tocompetent authorities and river basin districts shall be taken asreferences to the competent authorities and unit of managementreferred to in this Article. Member States shall inform theCommission of any changes in the information providedpursuant to this paragraph within three months of the changecoming into effect.

CHAPTER II

PRELIMINARY FLOOD RISK ASSESSMENT

Article 4

1. Member States shall, for each river basin district, or unitof management referred to in Article 3(2)(b), or the portion ofan international river basin district lying within their territory,undertake a preliminary flood risk assessment in accordancewith paragraph 2 of this Article.

2. Based on available or readily derivable information, suchas records and studies on long term developments, in particularimpacts of climate change on the occurrence of floods, a preli-minary flood risk assessment shall be undertaken to provide anassessment of potential risks. The assessment shall include atleast the following:

(a) maps of the river basin district at the appropriate scaleincluding the borders of the river basins, sub-basins and,where existing, coastal areas, showing topography andland use;

(b) a description of the floods which have occurred in the pastand which had significant adverse impacts on human health,the environment, cultural heritage and economic activityand for which the likelihood of similar future events isstill relevant, including their flood extent and conveyanceroutes and an assessment of the adverse impacts they haveentailed;

(c) a description of the significant floods which have occurredin the past, where significant adverse consequences ofsimilar future events might be envisaged;

and, depending on the specific needs of Member States, itshall include:

(d) an assessment of the potential adverse consequences offuture floods for human health, the environment, culturalheritage and economic activity, taking into account as far aspossible issues such as the topography, the position ofwatercourses and their general hydrological and geo-morphological characteristics, including floodplains as

natural retention areas, the effectiveness of existing man-made flood defence infrastructures, the position ofpopulated areas, areas of economic activity and long-termdevelopments including impacts of climate change on theoccurrence of floods.

3. In the case of international river basin districts, or units ofmanagement referred to in Article 3(2)(b) which are shared withother Member States, Member States shall ensure that exchangeof relevant information takes place between the competentauthorities concerned.

4. Member States shall complete the preliminary flood riskassessment by 22 December 2011.

Article 5

1. On the basis of a preliminary flood risk assessment asreferred to in Article 4, Member States shall, for each riverbasin district, or unit of management referred to in Article3(2)(b), or portion of an international river basin district lyingwithin their territory, identify those areas for which theyconclude that potential significant flood risks exist or mightbe considered likely to occur.

2. The identification under paragraph 1 of areas belonging toan international river basin district, or to a unit of managementreferred to in Article 3(2)(b) shared with another Member State,shall be coordinated between the Member States concerned.

CHAPTER III

FLOOD HAZARD MAPS AND FLOOD RISK MAPS

Article 6

1. Member States shall, at the level of the river basin district,or unit of management referred to in Article 3(2)(b), prepareflood hazard maps and flood risk maps, at the most appropriatescale for the areas identified under Article 5(1).

2. The preparation of flood hazard maps and flood risk mapsfor areas identified under Article 5 which are shared with otherMember States shall be subject to prior exchange of informationbetween the Member States concerned.

3. Flood hazard maps shall cover the geographical areaswhich could be flooded according to the following scenarios:

(a) floods with a low probability, or extreme event scenarios;

(b) floods with a medium probability (likely return period≥ 100 years);

(c) floods with a high probability, where appropriate.

ENL 288/30 Official Journal of the European Union 6.11.2007

4. For each scenario referred to in paragraph 3 the followingelements shall be shown:

(a) the flood extent;

(b) water depths or water level, as appropriate;

(c) where appropriate, the flow velocity or the relevant waterflow.

5. Flood risk maps shall show the potential adverse conse-quences associated with flood scenarios referred to in paragraph3 and expressed in terms of the following:

(a) the indicative number of inhabitants potentially affected;

(b) type of economic activity of the area potentially affected;

(c) installations as referred to in Annex I to Council Directive96/61/EC of 24 September 1996 concerning integratedpollution prevention and control (1) which might cause acci-dental pollution in case of flooding and potentially affectedprotected areas identified in Annex IV(1)(i), (iii) and (v) toDirective 2000/60/EC;

(d) other information which the Member State considers usefulsuch as the indication of areas where floods with a highcontent of transported sediments and debris floods canoccur and information on other significant sources ofpollution.

6. Member States may decide that, for coastal areas where anadequate level of protection is in place, the preparation of floodhazard maps shall be limited to the scenario referred to inparagraph 3(a).

7. Member States may decide that, for areas where floodingis from groundwater sources, the preparation of flood hazardmaps shall be limited to the scenario referred to in para-graph 3(a).

8. Member States shall ensure that the flood hazard mapsand flood risk maps are completed by 22 December 2013.

CHAPTER IV

FLOOD RISK MANAGEMENT PLANS

Article 7

1. On the basis of the maps referred to in Article 6, MemberStates shall establish flood risk management plans coordinated

at the level of the river basin district, or unit of managementreferred to in Article 3(2)(b), for the areas identified underArticle 5(1) and the areas covered by Article 13(1)(b) inaccordance with paragraphs 2 and 3 of this Article.

2. Member States shall establish appropriate objectives forthe management of flood risks for the areas identified underArticle 5(1) and the areas covered by Article 13(1)(b), focusingon the reduction of potential adverse consequences of floodingfor human health, the environment, cultural heritage andeconomic activity, and, if considered appropriate, on non-structural initiatives and/or on the reduction of the likelihoodof flooding.

3. Flood risk management plans shall include measures forachieving the objectives established in accordance withparagraph 2 and shall include the components set out in PartA of the Annex.

Flood risk management plans shall take into account relevantaspects such as costs and benefits, flood extent and floodconveyance routes and areas which have the potential toretain flood water, such as natural floodplains, the environ-mental objectives of Article 4 of Directive 2000/60/EC, soiland water management, spatial planning, land use, natureconservation, navigation and port infrastructure.

Flood risk management plans shall address all aspects of floodrisk management focusing on prevention, protection, prepa-redness, including flood forecasts and early warning systemsand taking into account the characteristics of the particularriver basin or sub-basin. Flood risk management plans mayalso include the promotion of sustainable land use practices,improvement of water retention as well as the controlledflooding of certain areas in the case of a flood event.

4. In the interests of solidarity, flood risk management plansestablished in one Member State shall not include measureswhich, by their extent and impact, significantly increase floodrisks upstream or downstream of other countries in the sameriver basin or sub-basin, unless these measures have been coor-dinated and an agreed solution has been found among theMember States concerned in the framework of Article 8.

5. Member States shall ensure that flood risk managementplans are completed and published by 22 December 2015.

Article 8

1. For river basin districts, or units of management referredto in Article 3(2)(b), which fall entirely within their territory,Member States shall ensure that one single flood riskmanagement plan, or a set of flood risk management planscoordinated at the level of the river basin district, is produced.

EN6.11.2007 Official Journal of the European Union L 288/31

(1) OJ L 257, 10.10.1996, p. 26. Directive as last amended by Regu-lation (EC) No 166/2006 of the European Parliament and of theCouncil (OJ L 33, 4.2.2006, p. 1).

2. Where an international river basin district, or unit ofmanagement referred to in Article 3(2)(b), falls entirely withinthe Community, Member States shall ensure coordination withthe aim of producing one single international flood riskmanagement plan, or a set of flood risk management planscoordinated at the level of the international river basindistrict. Where such plans are not produced, Member Statesshall produce flood risk management plans covering at leastthe parts of the international river basin district falling withintheir territory, as far as possible coordinated at the level of theinternational river basin district.

3. Where an international river basin district, or unit ofmanagement referred to in Article 3(2)(b), extends beyond theboundaries of the Community, Member States shall endeavourto produce one single international flood risk management planor a set of flood risk management plans coordinated at the levelof the international river basin district; where this is notpossible, paragraph 2 shall apply for the parts of the interna-tional river basin falling within their territory.

4. The flood risk management plans referred to in para-graphs 2 and 3 shall be supplemented, where considered appro-priate by countries sharing a sub-basin, by more detailed floodrisk management plans coordinated at the level of the interna-tional sub-basins.

5. Where a Member State identifies an issue which has animpact on the management of flood risks of its water and thatissue cannot be resolved by that Member State, it may reportthe issue to the Commission and any other Member Stateconcerned and may make recommendations as to how theissue should be resolved.

The Commission shall respond to any report or recommen-dations from Member States within a period of six months.

CHAPTER V

COORDINATION WITH DIRECTIVE 2000/60/EC, PUBLICINFORMATION AND CONSULTATION

Article 9

Member States shall take appropriate steps to coordinate theapplication of this Directive and that of Directive 2000/60/ECfocusing on opportunities for improving efficiency, informationexchange and for achieving common synergies and benefitshaving regard to the environmental objectives laid down inArticle 4 of Directive 2000/60/EC. In particular:

1. the development of the first flood hazard maps and floodrisk maps and their subsequent reviews as referred to inArticles 6 and 14 of this Directive shall be carried out insuch a way that the information they contain is consistentwith relevant information presented according to Directive2000/60/EC. They shall be coordinated with, and may beintegrated into, the reviews provided for in Article 5(2) ofDirective 2000/60/EC;

2. the development of the first flood risk management plansand their subsequent reviews as referred to in Articles 7 and14 of this Directive shall be carried out in coordination with,and may be integrated into, the reviews of the river basinmanagement plans provided for in Article 13(7) of Directive2000/60/EC;

3. the active involvement of all interested parties under Article10 of this Directive shall be coordinated, as appropriate, withthe active involvement of interested parties under Article 14of Directive 2000/60/EC.

Article 10

1. In accordance with applicable Community legislation,Member States shall make available to the public the preli-minary flood risk assessment, the flood hazard maps, theflood risk maps and the flood risk management plans.

2. Member States shall encourage active involvement ofinterested parties in the production, review and updating ofthe flood risk management plans referred to in Chapter IV.

CHAPTER VI

IMPLEMENTING MEASURES AND AMENDMENTS

Article 11

1. The Commission may, in accordance with the regulatoryprocedure referred to in Article 12(2), adopt technical formatsfor the purpose of processing and transmission of data,including statistical and cartographic data, to the Commission.The technical formats should be adopted at least two yearsbefore the dates indicated respectively in Articles 4(4), 6(8)and 7(5), taking into account existing standards as well asformats developed under relevant Community acts.

2. The Commission may, taking into account the periods forreview and updating, adapt the Annex to scientific and technicalprogress.

These measures, designed to amend non-essential elements ofthis Directive, shall be adopted in accordance with the regu-latory procedure with scrutiny referred to in Article 12(3).

Article 12

1. The Commission shall be assisted by the committee estab-lished under Article 21 of Directive 2000/60/EC.

2. Where reference is made to this paragraph, Articles 5 and7 of Decision 1999/468/EC shall apply, having regard to theprovisions of Article 8 thereof.

The period laid down in Article 5(6) of Decision 1999/468/ECshall be set at three months.

ENL 288/32 Official Journal of the European Union 6.11.2007

3. Where reference is made to this paragraph, Article 5a(1)to (4) and Article 7 of Decision 1999/468/EC shall apply,having regard to the provisions of Article 8 thereof.

CHAPTER VII

TRANSITIONAL MEASURES

Article 13

1. Member States may decide not to undertake the preli-minary flood risk assessment referred to in Article 4 for thoseriver basins, sub-basins or coastal areas where they have either:

(a) already undertaken a risk assessment to conclude, before 22December 2010, that a potential significant flood risk existsor might be considered likely to occur leading to the iden-tification of the area among those referred to in Article 5(1)or

(b) decided, before 22 December 2010, to prepare flood hazardmaps and flood risk maps and to establish flood riskmanagement plans in accordance with the relevantprovisions of this Directive.

2. Member States may decide to make use of flood hazardmaps and flood risk maps finalised before 22 December 2010,if such maps provide a level of information equivalent to therequirements of Article 6.

3. Member States may decide to make use of flood riskmanagement plans finalised before 22 December 2010,provided the content of these plans is equivalent to therequirements set out in Article 7.

4. Paragraphs 1, 2 and 3 shall apply without prejudice toArticle 14.

CHAPTER VIII

REVIEWS, REPORTS AND FINAL PROVISIONS

Article 14

1. The preliminary flood risk assessment, or the assessmentand decisions referred to in Article 13(1), shall be reviewed, andif necessary updated, by 22 December 2018 and every six yearsthereafter.

2. The flood hazard maps and the flood risk maps shall bereviewed, and if necessary updated, by 22 December 2019 andevery six years thereafter.

3. The flood risk management plan(s) shall be reviewed, andif necessary updated, including the components set out in part Bof the Annex, by 22 December 2021 and every six yearsthereafter.

4. The likely impact of climate change on the occurrence offloods shall be taken into account in the reviews referred to inparagraphs 1 and 3.

Article 15

1. Member States shall make available the preliminary floodrisk assessment, the flood hazard maps, the flood risk maps andflood risk management plans referred to in Articles 4, 6 and 7,as well as their review and, where applicable, their updates tothe Commission within three months after the dates indicatedrespectively in Articles 4(4), 6(8), 7(5) and 14.

2. Member States shall inform the Commission of thedecisions taken in accordance with Article 13(1), (2) and (3)and make available the relevant information thereon by thedates indicated respectively in Articles 4(4), 6(8) and 7(5).

Article 16

The Commission shall, by 22 December 2018, and every sixyears thereafter, submit to the European Parliament and to theCouncil a report on the implementation of this Directive. Theimpact of climate change shall be taken into account in drawingup this report.

Article 17

1. Member States shall bring into force the laws, regulationsand administrative provisions necessary to comply with thisDirective before 26 November 2009. They shall forthwithinform the Commission thereof.

When they are adopted by Member States, these measures shallcontain a reference to this Directive or shall be accompanied bysuch reference on the occasion of their official publication. Themethods of making such reference shall be laid down byMember States.

2. Member States shall communicate to the Commission thetext of the main provisions of national law which they adopt inthe field covered by this Directive.

Article 18

This Directive shall enter into force on the 20th day followingits publication in the Official Journal of the European Union.

Article 19

This Directive is addressed to the Member States.

Done at Strasbourg, 23 October 2007.

For the European ParliamentThe President

H.-G. PÖTTERING

For the CouncilThe President

M. LOBO ANTUNES

EN6.11.2007 Official Journal of the European Union L 288/33

ANNEX

A. Flood risk management plans

I. Components of the first flood risk management plans:

1. the conclusions of the preliminary flood risk assessment as required in Chapter II in the form of a summarymap of the river basin district, or the unit of management referred to in Article 3(2)(b), delineating the areasidentified under Article 5(1) which are the subject of this flood risk management plan;

2. flood hazard maps and flood risk maps as prepared under Chapter III, or already in place in accordance withArticle 13, and the conclusions that can be drawn from those maps;

3. a description of the appropriate objectives of flood risk management, established in accordance with Article 7(2);

4. a summary of the measures and their prioritisation aiming to achieve the appropriate objectives of flood riskmanagement, including the measures taken in accordance with Article 7, and flood related measures taken underother Community acts, including Council Directives 85/337/EEC of 27 June 1985 on the assessment of theeffects of certain public and private projects on the environment (1) and 96/82/EC of 9 December 1996 on thecontrol of major accident hazards involving dangerous substances (2), Directive 2001/42/EC of the EuropeanParliament and of the Council of 27 June 2001 on the assessment of the effects of certain plans andprogrammes on the environment (3) and Directive 2000/60/EC;

5. when available, for shared river basins or sub-basins, a description of the methodology, defined by the MemberStates concerned, of cost-benefit analysis used to assess measures with transnational effects.

II. Description of the implementation of the plan:

1. a description of the prioritisation and the way in which progress in implementing the plan will be monitored;

2. a summary of the public information and consultation measures/actions taken;

3. a list of competent authorities and, as appropriate, a description of the coordination process within anyinternational river basin district and of the coordination process with Directive 2000/60/EC.

B. Components of the subsequent update of flood risk management plans:

1. any changes or updates since the publication of the previous version of the flood risk management plan, includinga summary of the reviews carried out in compliance with Article 14;

2. an assessment of the progress made towards the achievement of the objectives referred to in Article 7(2);

3. a description of, and an explanation for, any measures foreseen in the earlier version of the flood risk managementplan which were planned to be undertaken and have not been taken forward;

4. a description of any additional measures since the publication of the previous version of the flood risk managementplan.

ENL 288/34 Official Journal of the European Union 6.11.2007

(1) OJ L 175, 5.7.1985, p. 40. Directive as last amended by Directive 2003/35/EC of the European Parliament and of the Council(OJ L 156, 25.6.2003, p. 17).

(2) OJ L 10, 14.1.1997, p. 13. Directive as last amended by Directive 2003/105/EC of the European Parliament and of the Council(OJ L 345, 31.12.2003, p. 97).

(3) OJ L 197, 21.7.2001, p. 30.

List of Authors

Affinita MariaRegione CampaniaAutorità di Bacino Regionale in Destra SeleNapoli ITALY

Alfieri LorenzoEuropean Commission - Joint Research Centre Institute for Environment and SustainabilityIspra ITALY

Bateman Pinzon AllenGITS – Barcelona Tech Hydraulic Coastal and Environmental Engineering Barcelona SPAIN

Beven KeithLancaster Environment CentreLancaster UniversityLancaster UNITED KINGDOM

Bovolin VittorioDepartment of Civil Engineering University of Salerno Fisciano ITALY

Bregoli Francesco GITS – Barcelona Tech Hydraulic Coastal and Environmental Engineering Barcelona SPAIN

Bresciani RiccardoIridra s.r.l. Firenze ITALY

Cabello AngelsCETaqua U2 Cornellà de Llobregat SPAIN

Carbone Antonio Studio Geores - Geologia e Geomorfologia Salerno ITALY

Cestari AntonelloCUGRI Department of Civil EngineeringUniversity of SalernoFisciano ITALY

Chevalier GuillaumeGITS – Barcelona Tech Hydraulic Coastal and Environmental Engineering Barcelona SPAIN

Ciervo Fabio Department of Civil EngineeringUniversity of SalernoFisciano ITALY

Coccia G.Idrologia e Ambiente Srl Idrologia Napoli ITALY

Cuomo AlbinaDepartment of Civil EngineeringUniversity of SalernoFisciano ITALY

D'Onofrio Gianluca Regione Campania Autorità di Bacino Regionale in Destra Sele Napoli ITALY

De Luca Carmine Department of Civil EngineeringUniversity of SalernoFisciano ITALY

Dottori F.Department of Earth, Geological and Environmental Sciences, University of BolognaBologna ITALY

Ehret U.Karslruhe Institue for TechnologyKarslruhe CH.

Escaler I.CETaqua DTCornellà de Llobregat

Dentale Fabio Maritime Engineering DivisionDepartment of Civil Engineering University of Salerno Fisciano ITALY

Donnarumma Giovanna Maritime Engineering DivisionDepartment of Civil Engineering University of Salerno Fisciano ITALY

Egashira ShinjiNEWJECOsaka JAPAN

Faraci C.Department of Civil Engineering University of Messina Messina ITALY

Fariello Luigi Regione Campania Autorità di Bacino Regionale in Destra Sele Napoli ITALY

Ferrer M.HYDS - Barcelona SPAIN

Foti E.Department of Environmental and Civil EngineeringUniversity of CataniaCatania ITALY

Fundel F.WSL Hydrological Forecasts Birmensdorf SWITZERLAND

Furcolo Pierluigi Department of Civil EngineeringUniversity of SalernoFisciano ITALY

Gallo Antonio Studio Geores - Geologia e Geomorfologia Salerno ITALY

Genovese Marco Department of Civil Engineering University of Salerno Fisciano ITALY

Germann Urs MeteoswissRadar meteorologyLocarno-Monti, CH.

Grimaldi Giuseppe Regione Campania Autorità di Bacino Regionale in Destra Sele Napoli ITALY

Guida Domenico Department of Civil Engineering University of Salerno Fisciano ITALY

Guna V.HidroGaia S.L.Valencia SPAIN

Gusmaroli Giancarlo CIRF Technical Secretariat Member Venezia ITALY

Hazenberg Pieter Wageningen University Hydrology and Quantitative Water Management Wageningen NETHERLANDS

Iannella Sergio Regione Campania Autorità di Bacino Regionale in Destra Sele Napoli ITALY

Liechti K.WSL Hydrological Forecasts Birmensdorf SWITZERLAND

Llort Xavier HYDS - Barcelona SPAIN

Lombardi Gerardo Regione Campania Autorità di Bacino Regionale in Destra Sele Napoli ITALY

Longobardi Antonia Department of Civil Engineering University of Salerno Fisciano ITALY

Martino RiccardoDept. of Hydraulic, Geotechnical and Environmental University of Napoli Federico IINapoli ITALYMastropaolo SilvanoPalermo ITALY

Medina VicenteGITS - BarcelonaTech Hydraulic Coastal and Environmental Engineering Barcelona SPAIN

Minotta Crescenzo Regione Campania Autorità di Bacino Regionale in Destra Sele Napoli ITALY

Monaco Marina Department of Civil Engineering University of Salerno Fisciano ITALY

Moretta Filomena Regione Campania Autorità di Bacino Regionale in Destra Sele Napoli ITALY

Musumeci R.Department of Environmental and Civil EngineeringUniversity of CataniaCatania ITALY

Nardini AndreaCIRF Technical Secretariat Venezia ITALY

Nicolosi V.Sicilian Region Department of Civil ProtectionMessina ITALY

Ortiz Enrique Idrologia e Ambiente Srl Idrologia Napoli ITALY

Palmieri VincenzoARCADISNapoli ITALY

Panziera Luca MeteoSwiss RASA Locarno SWITZERLAND

Papa Maria Nicolina Department of Civil EngineeringUniversity of SalernoFisciano ITALY

Pavan Sara CIRF Technical Secretariat Venezia ITALY

Pelosi Anna Department of Civil EngineeringUniversity of SalernoFisciano ITALY

Pugliese Carratelli EugenioCUGRI Department of Civil EngineeringUniversity of SalernoFisciano ITALY

Rodriguez Alvaro HYDS HYDS Barcelona SPAIN

Rossi FabioDepartment of Civil Engineering University of Salerno Fisciano ITALY

Sanchez-Diezma Rafael HYDS - Barcelona SPAIN

Santiago Antonio Agencia de Medio Ambiente y Agua Risks analysis Unit Córdoba SPAIN

Sarno LucaDept. of Hydraulic, Geotechnical and Environmental University of Napoli Federico IINapoli ITALY

Schmid M.WSL Hydrological Forecasts Birmensdorf SWITZERLAND

Sempere Torres Daniel Universitat Politècnica de Catalunya CRAHI Barcelona SPAIN

Siervo VincenzoCUGRI Department of Civil EngineeringUniversity of SalernoFisciano ITALY

Smith Paul Lancaster University LEC Lancaster UNITED KINGDOM

Soreca Salvatore Stage at Autorità di Bacino Destra Sele -Benevento ITALY

Sorvino Luigi StefanoBasin Regional Authority Sele Southern CampaniaNapoli ITALY

Stancanelli Laura Maria Department of Environmental and Civil EngineeringUniversity of CataniaCatania ITALY

Thielen-del Pozo Jutta European Commission DG Joint Research Centre Ispra ITALY

Todini EzioDepartment of Earth, Geological and Environmental Sciences, University of BolognaBologna ITALY

Trentini Giuliano CIRF Italian Center for River Restoration Vietri sul Mare ITALY

Trezza Claudia Maritime Engineering DivisionDepartment of Civil EngineeringUniversity of Salerno

Uijlenhoet RemkoWageningen University Hydrology and Quantitative Water Management Wageningen NETHERLANDS

Varese PaoloCIRF Italian Center for River RestorationITALY

Velasco Marc CETaqua U2 Cornellà de Llobregat SPAIN

Versini Pierre-Antoine Universitat Politècnica de Catalunya CRAHI Barcelona SPAIN

Viccione Giacomo Department of Civil EngineeringUniversity of SalernoFisciano ITALY

Villani Paolo Department of Civil EngineeringUniversity of SalernoFisciano ITALY

Zappa Massimiliano WSL Hydrological Forecasts Birmensdorf SWITZERLAND

Zinzi Angelo Università degli Studi di Napoli "Parthenope" Dipartimento di Scienze per l'Ambiente Naples ITALY