European Commission Community Research
Workshop “Climate change impacts on the water cycle, resources and quality – Research- policy interface“ on 25-26th September 2006, Brussels Session 3: Economic and social implications implied by the climate change induced changes of water cycle and resources
Long-Term Planning of Flood Risk Management Jochen Schanze Leibniz Institute of Ecological and Regional Development (IOER), Dresden Member of the Dresden Flood Research Center (D-FRC)
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Contents 1. The concept of flood risk management in the long-term 2. Demands due to climate change and other dynamic factors 3. State of the art on European and national level 4. Reflection of current European Water Policy 5. Conclusions
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Contents 1. The concept of flood risk management in the long-term 2. Demands due to climate change and other dynamic factors 3. State of the art on European and national level 4. Reflection of current European Water Policy 5. Conclusions
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
„Risk“ in terms of Floods X Overall term: Risk = Probability * (negative) Consequence X Flood risk = Flood hazard * (exposure) * Flood vulnerability whereof vulnerability = value * susceptibility FLOODsite-Consortium (2005)
Hazard
Risk
Vulnerability
(intensity, probability)
(probability of social, economic and ecological damages)
(social, economic, ecological values, susceptibility)
(Exposure) FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Principal causal relations of flood risks Source e. g. rainfall, snowmelt, waves
“Source-Pathway-ReceptorConsequence” (SPRC-Model) Kundzewicz, Samuels (1997), ICE (2001)
Pathway e. g. overtopping, overflow, flood plain inundation
“Flood risk system” Receptor e. g. people , property , environment
(negative) Consequence e. g. loss of life, stress, material damage , environmental degradation
FRC
Dresden Flood Research Center
Schanze (2005, 2006)
Model concept of the “flood risk system” Sources
Catchment and flood plain (anthropogenic factors)
Catchment
Pathways
Flood plain
Size and shape (catchment)
Size and shape (flood plain)
Size and shape (flood plain)
Topography
Morphology (flood plain)
Morphology (flood plain)
Vegetation, soil
Vegetation structure, soil substrate, (flood plain)
Plants and animals, soil
(Hydro-)Geology
Groundwater
Groundwater
Additional water storage (i.e. snow cover)
Tributaries
Backwater of tributaries
River section i-1
River section i-2
River section i-3
Weather/ conditions
Meteorological event (Temperature, Precipitation)
Channel morphology
Channel morphology
Discharge, matter load
Water level, flow velocity, flood duration, matter deposition
Storage and regulation structures
Storage and regulation structures
Flood protection facilities
Runoff concentration
Flood wave propagation
Inundation
Sealing, emission of substances
Changes of flora and fauna, sedimentation and soil contamination due to manmade modification of floods (ecological “damages”)
Changes of groundwater due to man-made modifications of floods (ecological damages)
Channel morphology
Discharge (incl. ice blockage), matter load incl. retention/accumulation
Probability of certain flood events
Buildings, facilities, infrastructure
Direct and indirect damages for households, trade, industry and cultural heritage (economic and cultural “damages”)
Flow obstacles (urban areas, built structures, etc.)
Humans
Loss of life, health impacts, social effects (social “damages”)
Land use (flood plain)
Agricultural crops and farm animals
Direct and indirect damages (agriculture and forestry) (economic “damages”)
Flood protection facilities
Decentralised/local flood retention
Emissions
(Negative) Consequences
FLOOD RISK
Channel (flood wave)
Catchment and flood plain (naturogenic factors)
Atmosphere
Receptors
Pathways
Land use (catchment area)
+ (more regional)
Scale
(more local)
-
Schanze & Luther (i.p)
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Tasks and components of flood risk management Flood risk management
Risk reduction
Risk assessment
Risk analysis
Hazard determination
Vulnerability determination
Risk determination
Risk perception
Risk weighing
Pre-flood reduction
Probability and features (e.g. water depth, flow velocity, duration) of flood events
Potential social, economic and ecological damage depending on value and susceptibility referring to a certain type of hazard
Probability of certain social, economic and ecological damage referring to a certain hazard
Overall view of risk held by a person or group depending on cultural and personal values, experiences and feelings
Agreement on tolerability of risk weighing benefits and costs depending on individual or collective perception and interest
Physical measures, regulatory, financial and communicative instruments to reduce the risk by prevention and/or preparedness
Flood event reduction
Post-flood reduction
Physical Physical measures, measures, regulatory regulatory, instruments financial and and communicative communicative instruments activities to to deal with reduce the risk existing flood of an ongoing damages event
(Schanze 2006a)
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
How are flood risks governed by the society? ► Society, represented by politicians, experts and individuals, is the “managing entity” (cf. Parker 2000). ► These actors need information on existing or future flood risks and assess their tolerability. They formulate, implement and control strategies for risk reduction. ► Due to manifold interrelations between man and floods the “managing entity” is based on a multi-actor constellation: → several sectors (e.g. water and spatial planning authorities) → adjacent areas (e.g. multiple municipalities) → different levels (e.g. local, regional, national) ► Each actor has a specific institutional context, certain tasks and competences and in principle operates independently. FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
A basic framework of flood risk management Actor 1
Formulation and implementation of strategies
Risk assessment
Risk analysis
Actor n
Risk reduction
Risk perception Hazard determination
Vulnerability determination
„Cost“ of damages or measures
Determination of flood risk
„Benefits“ of use
Weighing flood risk
Preflood
Flood event
Post-flood
Strategic alternatives for flood risk mitigation
(Schanze et al. 2006)
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Process model of flood risk management Society (Context)
Flood Risk Management Actor 1 Formulation / implementation of strategies Actor n
Risk analysis
Risk assessment
Risk reduction
Flood risk system (Water basin/coastal cell with hazard and vulnerability
FRC
Dresden Flood Research Center
(Schanze 2006a)
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Circle of flood risk management modes
Post-flood recovery
Pre-flood design and implementation
Relief, cleaning, reconstruction, organisational and financial aid, etc.
Spatial planning, retention measures (source areas, pathways), preparedness, insurances, etc. Flood event management
Early warning, reservoir control, defence measures, evacuation, rescue, etc. FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Modes of flood risk management
Society (Context)
Flood Risk Management
Pre-flood design
Pre-flood implemen -tation
Flood event management
Post-flood recovery
Flood risk system (Water basin/coastal cell with hazard and vulnerability
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Definition of flood risk management ► Holistic and continuous societal analysis, assessment and reduction of flood risk. ► These activities refer to the whole “flood risk system” with its natural and societal dynamic. ► Due to manifold interrelations between man and floods they depend on societal decision-making processes in several sectors, adjacent areas and on several levels. ► The interrelations and the decision making vary regarding the type of water (e.g. river, coast), the type of flood (e.g. flash flood), the natural (e.g. uplands) and societal conditions (e.g. culture). (Schanze 2005, 2006b)
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Long-term planning of flood risk management
Society (Context)
Flood Risk Management
Pre-flood design
Pre-flood implemen -tation
Flood event management
Post-flood recovery
Flood risk system (Water basin/coastal cell with hazard and vulnerability
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Contents 1. The concept of flood risk management in the long-term 2. Demands due to climate change and other dynamic factors 3. State of the art on European and national level 4. Reflection of current European Water Policy 5. Conclusions
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Principle impacts of climate change on long term FRM
Predicted climate change with respect to temperature for various scenarios calculated with different Global Cirkulation Models (GCM) (IPCC 2001)
FRC
Dresden Flood Research Center
►
Anticipation of climate change is restricted to scenarios with manifold assumptions (knowledge uncertainty).
►
Downscaling of recent climate change projections and hydrological analysis indicate a tendency of more frequent and intensive flood events in Europe.
►
Results differ depending on the regional conditions (regional variability).
►
They also vary referring to the downscaling method and the combination of climatic and hydrological models applied (model uncertainty).
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Other dynamic factors of futures (overview) Source (Atmosphere and catchment)
Receptors
Consequences
Trends (autonomous developments through specific drivers)
- Climate change - Land-use - Land-use change change - Technical and economic development (defences)
- Land-use change - Technical and economic development
-Technical and economic development - Values and attitudes
Strategic alternatives (combinations of physical measures and policy instruments)
- On-site flood retention - Spatial planning - Land management
- Dikes, walls - Building construction - Spatial planning - Land management - Warning, evacuation
- Insurance - Other compensatory aid
Other assumptions
FRC
Pathways
Dresden Flood Research Center
- Reservoirs - Flood polders - River training - Flood defence - Spatial planning
- Dike breach
- Overlap with other risks
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Parameter y
Long-term planning based on explorative scenarios and scenario analysis
Scenario A (tn) = trend A (tn) * strategic alternative A (tn)
System state for scenario A
ex ante analysis
System variable x
Scenario A 0
Scenario B Scenario B (tn) = trend B (tn) * strategic alternative B (tn)
ex ante analysis
System state for scenario B Zeit
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Demands for long-term flood risk management
FRC
1.
A strategic planning approach should be applied exploring and reflecting alternative systemic scenarios and their most accurate analysis (favorable considering alternative methods)
2.
Physical measures and policy instruments decided on should follow precautionary principles and ensure flexibility and robustness under the given uncertainties.
3.
Management of flood and multiple risks should be based on learning on effects of previous decisions and the system development as well as on consistent behaviour of decision makers with emergent decision-making pattern.
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Contents 1. The concept of flood risk management in the long-term 2. Demands due to climate change and other dynamic factors 3. State of the art on European and national level 4. Reflection of current European Water Policy 5. Conclusions
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Meaning of and increase in major natural disasters (A) and economic losses (B) since 1950 worldwide
(Munich Re 2003)
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Approaches to derive storylines for scenario development
(Luther i.p.)
FRC
Dresden Flood Research Center
(Alterra 2004)
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Foresight: Developing Future Storylines
(Sayers 2004, Foresight Future Flooding 2100, UK)
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Foresight: People at risk present day & 2080s Number of people within the indicative flood plain Present Day (No of People) Negligible(< 250) Low (250 to 2,500) Medium (2,500 to 25,000) High (> 25,000)
2080s Decrease Negligible change Low increase Medium increase High increase
Present Day
Global Sustainability Responsibility 2080s
World Markets 2080s
(HRW 2004)
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Model system to simulate the flood risk system (VERIS-Elbe) Climate Change LISFLOOD Settlement Dike/Flood polder
SMS
WAVOS WAVOS
SMS
Management of river and flood plain
HOWAD Change/Management of land use
Digital Terrain Model
Multicriteria Extreme Value Statistics Explanation: HOWAD – Flood Damage Simulation Model, LISFLOOD – Rainfall-Runoff Model, SMS – 2Dhydrodynamic-numerical Surface Water Modelling System, WAVOS – Water Level Prediction System
(Schanze et al. 2006)
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Hydrodynamic inundation modelling (1d, 2d, 3d) and high resolved vulnerability modelling
(Meinel & Schumacher 2005)
FRC
Dresden Flood Research Center
(Hennersdorf & Deilmann 2006)
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Specification of building types (representatives) Using characteristic values: - Geometry - Function / Use - Construction specifics - Refurbishment costs - Synthetic cost function based on construction work items < 30 cm below 1 floor ceiling < 100 cm above 1 floor < 10 cm above 1 floor < 30 cm below ground floor ceiling < 100 cm above ground floor < 10 cm above ground floor < 30 cm entry level below cellar ceiling
< 30 cm above cellar floor
(Deilmann et al. 2006)
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
FLOODsite: Flood defence present day, 2030s, 2100s Policy P1: z No active intervention (including flood warning and maintenance). The ‘do-nothing’ policy. No work on defences and no operation of moveable structures. Policy P3: z Continue with existing or alternative actions to maintain the current flood risk management regime (accepting that flood risk will increase over time from this baseline). Defences maintained at current levels and condition. Moveable structures operated. (HRW 2006)
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
FLOODsite: P1 (top) and P3 (bottom) – 2030s
(Preliminary results of test runs; HRW 2006)
(Preliminary results of test runs; HRW 2006)
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
FLOODsite: High Emissions CC Scenario, P3 – 2100
(Preliminary results of test runs; HRW 2006)
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Resilience strategies based on building construction / flood proofing
(Kreilung Architekten 2003)
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Kön
Par
Pil
Aus
Süd
Extreme flood
Che
Elb
Ste
ELLA: Flood areas in water management maps
ÜG
ÜG/AZ
ÜG/AZ
RB
Historical flood 200 year flood
*
100 year flood 50 year flood 20 year flood 5 year flood Implement. as
VR
NÜ/ÜG
V
(ÜG/AZ) ÜG/AZ
NÜ
Transfer of information
AZ
Active Zone
ÜG
Flood protection area
RB
„Risk area“
AZ
Potenzial flood area
VR
Priority area
V
VR, VB, VRS
VB
Reserve function area
(Nobis & Schanze 2006)
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Süd
Kön
Par
Pil
Aus
Che
Elb
Ste
ELLA: Implementation of flood areas in spatial plans
Lim
indiv
ES
Extreme flood Historical flood
Lim
200 year flood 100 year flood 50 year flood
mark
20 year flood
mark
5 year flood Implement. as
VR
VR
VR/VB
Lim
VR
Priority area
VB
Reserve function area
Lim
Limits
VB/Lim
ES
Existing settlements
indiv
Individual determination
mark
Additinally marked (Nobis & Schanze 2006)
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
FLOODsite: DSS tools as additional instruments for decision making Climate and land -use change Meteorological model Hydrological models Hydrodynamic model
Ecological model
Dam breach model ?
Uncertainty ?
Loss of life Model?
Damage model HOWAD
Applicability ?
Multicriteria assessment
FLOODsite Pilot Studysystem "Elbe (DSS) River Basin" Desicion support FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
FLOODsite: Developing strategies by actors of flood risk management Society (Context)
Flood Risk Management
Pre-flood design
Pre-flood implemen -tation
Flood event management
Post-flood appraisal
Water basin / coastal cell with hazards and vulnerability
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
How does the process of developing strategies happen? ► Strategies are understood as “consistent combination of long-term goals, aims, and measures, as well as process patterns that is continuously aligned with the societal context“ (Hutter 2006). ► This means developing strategies in terms of flood risk management is not limited to the content of measures resp. instruments and the context of the actors. Moreover, it includes the process of formulating and implementing strategies.
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Dimensions of strategies (Hutter & Schanze i.p.)
Content External: • Political • Legal • Social • Economic Internal: • Politics • Resources • Responsibility • Culture • Capabilities
Societal context FRC
• General aims and specific targets • Strategic alternatives as combinations of measures and instruments • Technical measures and policy instruments • System analysis: controllable, not controllable variables Process • Models of formulation and implementation: linear, adaptiv • Strategic planning modes: programming, scenario-based planning, etc. • Learning processes at different levels: individual, group, organisation, network
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Linear and fragmented process model of flood risk management Society (Context)
Flood Risk Management Actor 1 Formulation and implementation of strategies Actor n
Risk analysis
Risk assessment
Risk reduction
Flood risk system (Water basin/coastal cell with hazard and vulnerability
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Adaptive and co-operative process model of flood risk management Society (Context)
Flood Risk Management Actor 1 Formulation / implementation of strategies Actor n
Risk analysis
Risk assessment
Risk reduction
Flood risk system (Water basin/coastal cell with hazard and vulnerability
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Contents 1. The concept of flood risk management in the long-term 2. Demands due to climate change and other dynamic factors 3. State of the art on European and national level 4. Reflection of current European Water Policy 5. Conclusions
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Reflection of EU Water Policy Floods Directive X Art. 4, 2c of the political agreement of the Council considers the relevant factors of the flood risk system “… long-term developments including impacts of climate change on the occurrence of floods”: This seems to be a good prerequisite to include knowledge on possible futures in FRM X To strengthen future flood risks it would be valuable also to consider them explicitly in flood hazard and risk maps (Chapt. III) and in flood risk management plans (Chapt. IV) X The determination of the probability of extreme events at least covers climate change scenarios (not societal scenarios) X A specification of the use of holistic scenarios could be reached based on future guidance documents. FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Reflection of EU Water Policy Water Framework Directive (WFD) X The proposed coordination of the Floods Directive with the WFD allows an identification of partly increasing conflicts between water quality and flood risk issues due to climate change. X Therefore, the implementation of the WFD should be enhanced referring to climate change. X To better cover probable conflicts between the aims and measures of both instruments, river basin and flood risk management should be compiled as two separate but well integrated items in a comprehensive plan.
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Reflection of EU Water Policy 7th Framework Programme (1) X Methodologies on integrated and regionalised scenarios of flood risk systems should be improved dealing with all significant factors, drivers and probable options of combined resistance and resilience strategies for adaptation. X Analyses of such futures need the further development of coupled interdisciplinary simulation models with a specification of their uncertainties. Currently, model uncertainties seem partly to be higher than impacts of climate change. X Improvements should regard to the interfaces between climatic downscaling and hydrological models as well as between hydrodynamic models and methods for vulnerability analyses.
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Reflection of EU Water Policy 7th Framework Programme (2) X Methods for vulnerability analyses required a better resolution to more validly determine climate change impacts and to calculate risks in comparison to benefits of using flood zones. X Regarding policy instruments and the management processes, an enhancement of current social and planning science knowledge is needed. Real-world planning seems to be crucial for the effectiveness of risk reduction efforts for European citizens. X Climate and societal dynamics especially require the treatment of different time horizons with different levels of accuracy and instruments which for instance should reflect experiences from strategy research. FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Contents 1. The concept of flood risk management in the long-term 2. Demands due to climate change and other dynamic factors 3. State of the art on European and national level 4. Reflection of current European Water Policy 5. Conclusions
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Conclusions
FRC
X
Comprehensive scenarios of future states of flood risk systems considering climate and societal change and risk reduction measures and instruments seem to be important to explore decision options.
X
Simulation of such systems with highly resolved interdisciplinary model systems are needed including appropriate interfaces to climatic downscaling models.
X
More attention should be paid on the societal strategy development in flood risk management processes.
X
EU Water Policy already provides conditions for an incremental and adaptive flood risk management.
X
Guidance for a strategic planning approach should be derived from current and future research results in the areas specified above. Herby, success depends on a fruitful exchange between science and practice.
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
Acknowledgement X The presentation is predominantly based on results of the IP FLOODsite funded by the European Commission under the 6th EU Framework Programme (EC Contract-No. GOCE-CT-2004-505420).
www.FLOODsite.net X Futhermore, the following research project have been considered: - VERIS-Elbe (www.veris-elbe.ioer.de) - Foresight Future Flooding Project (www.foresight.gov.uk) - INTERREG project ELLA (www.ella.net)
FRC
Dresden Flood Research Center
Leibniz Institute of Ecological and Regional Development (IOER) Dresden
“Flood risk management is about co-evolution of societies with one dynamic extreme of the water cycle.”
Thank you for your Attention.
FRC
Dresden Flood Research Center
