CAU Kiel Task 27 LWI Braunschweig German Bight Coast€¦ · Development of a modern risk analysis tool: integrated, transferable, micro-scale and probabilistic! Testing special parts

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Workshop No. 5 - Grenoble, 11-15 February 2008 GOCE-CT-2004-505420

Task 27German Bight Coast

CAU KielLWI Braunschweig

H. Sterr, A. Kortenhaus, G. Kaiser, S. Hofmann

213 February 2008 Workshop No. 5 - Grenoble

Study Area

North Sea

Baltic Sea

St. Peter-Ording

Hazard analysis Vulnerability analysis MCA & risk mapping Outlook

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Objectives! Combination of probabilistic flood defence

failures with micro-scale socio-economic damage potentials

! Development of a modern risk analysis tool: integrated, transferable, micro-scale and probabilistic

! Testing special parts of the flood risk management (FRM) methodology of FLOODsite for a coastal site



Risk = Probability × Consequences

Affected receptors and their value:

Economic

Social

Ecological

Source

↓

Pathways

↓

Probability of coastal defence

failure


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General Approach

Hazard analysisHazard analysis Vulnerability analysisVulnerability analysis

Flood scenariosFlood scenarios

Risk analysis toolRisk analysis tool

Risk zone mapping for flood scenariosRisk zone mapping for flood scenarios



Hazard analysis


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Approach! Division in dike sections! Input parameter for each section

" Water level" Geometry of coastal defence structures" Geotechnical parameters

! Fault tree for each section! Failure probability for each section! Overall failure probability for all sections



6.016.000

6.017.000

6.018.000

6.019.000

6.020.000

6.021.000

6.022.000

6.023.000

6.024.000

6.025.000

3.473.000 3.474.000 3.475.000 3.476.000 3.477.000 3.478.000 3.479.000 3.480.000 3.481.000 3.482.000

x- Coordinate

Y C

oord

inat

e

Dike line St. Peter Ording

Sections1

245

6

7

3

89

10

1112 13

Dunes

Section numbers


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Fault tree for one dike sectionFlooding of hinterland

5.4⋅10-5

Breach3.1⋅10-6

Wave Overtopping4.0⋅10-5

Overflow1.1⋅10-5

Failure outer slope5.8⋅10-8

Failure dike top< 1.0⋅10-10

Failure inner slope< 1.0⋅10-10

Sliding3.0⋅10-6

Non-structural failure5.1⋅10-5



Results and parameters! Results

" Failure probability for each section" Total flooding probability

! Key parameters" Water level and crest height" Wave height and -period


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Flood scenarios and simulation



Scenarios

Scenario 1: Wave overtoppingScenario 2: Dike breach


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Simulation St. Peter-Ording! Elevation data: DEM5 (12,5 m)! Model: SOBEK (2D-1D)! Scenarios: Overtopping dike and

Dike breach (100 m)! Input parameter: Hs = 1,60 m

Tp = 6,0 sd = 5,3 mNNStorm surge history

! Time/Simulation: 13 h



Wat

er le

vel:

5,30

m


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Results and parameters! Results

" Inundation area" Inundation height" Velocity" (Duration)

! Key parameters" Water level outside" Breach widths" Roughness parameter



Vulnerability analysis


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Approach

Micro-scale vulnerability analysis

� Use of high resolution data (DEM5, ALK)� Multi-criteria analysis� Standardisation of the method for value

assessment



Multi-criteria analysis (MCA)

Integration of different vulnerability categories


SOCIAL

ECONOMIC

ECOLOGICAL

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Assets at risk:- Buildings- Private inventory- Stock value- Gross value added

Vulnerability classes: Economic



Vulnerability classes: Social

Assets at risk:- Population at risk (& risk to life)

- Vulnerable people- Social hotspots


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Vulnerability classes: Ecological

Assets at risk: - Coastal biotopes (Dunes, Forest, Wetland, Grassland)



Inventory13.59%

Recreational areas0.68%

Cost of evacuation0.42%

Live stock1.04%

Stock values2.50%

Wind enery plants0.01%

Vehicles0.49%

Traffic areas3.37%

Gross value added15.82%

Fixed assets15.81%

Buildings46.28%

Standardised method for value assessmentReduction of damage categories


~ 90 %

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Standardised method for value assessment

Floor area * mean number of employees * mean GVA/employee

StatisticsGross value added

Mean value for every floor for each economic sector

Telephone interviews with selected companies in the AOI

Fixed assets

Floor area * mean inventory value �/m², according to building type

Telephone interviews with insurance companies

Inventory

Calculation with standardised, region basedbuilding-values/m²

approx. 100 different building types (age, base area, floors,..)

Buildings

FLOODsiteMERK (2003)



Results

m²DunesForestWetlandGrassland

Coastal biotopesEcological

Number6 schools and kindergartens4 clinics5 children�s clinics / homes 1 youth recreation home1 boarding school1 nursing home

Social Hot spots

Number> 70 years: 639 people < 8 years: 181 peopleInvalid persons: 1231 beds in clinics**

Vulnerable groups

Number2065 + tourists 513p/day*Hazard zone inhabitants tourists0-50 m 0 050-100 m 151 37100-250 m 448 112250-500 m 755 188500-1000 m 711 176

People at risk

Social

EUR63.398.686Total

EUR52.973Gross value added

EUR24.779.280Fixed assets

EUR20.062.292Inventory

EUR12.740.624Buildings

Economic

MeasureDamage(Standard scenario, 5.30m)Risk criteria

Risk category


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Multi-criteria risk assessment and

risk zone mapping



Approach! Weighting of economic, social and

environmental risk categories! Testing 2 approaches:

" Disjunctive (thresholds)" MAUT

! Risk zoning


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MAUT (multi-attribute utility theory) approach! All criteria is aggregated to a single scalar

factor (possible to compare �apples and oranges�)

! Weighting factors! Each criteria in economic, social and

environmental categories get rating values 1-10

! Each category is weighted (here each 1/3)

# RISK ZONES 0-10



Risk zonesHazard analysis Vulnerability analysis MCA & risk mapping Outlook

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Risk analysis tool



Approach

! Combination of:" hazard probability" flood scenarios" micro-scale vulnerability assessment

! Integrated and transferable approach to assess economic, social and ecological risk criteria

! Multi-layer GIS output as an appropriate tool for the spatial analysis of flood risk


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Risk analysis tool

Economic

BuildingsPrivate inventoryFixed assetsGVA

Water level Wave parametersType of flood eventGeometryBreach scenarioFriction parameter

Risk Rating

GIS based Map Output

Vulnerability Criteria Hazard Probability

People at riskSocial hotspotsVulnerable people

Coastal biotopes

Flood scenarios

Social Ecological



Links, dissemination and lessons learned


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Project linksHazard analysis Vulnerability analysis MCA & risk mapping Outlook

Task 27Task 27

Flood scenarios

Vulnerability analysis

Hazard analysis

Risk reception

Risk analysis toolRisk analysis tool Risk zone mappingRisk zone mapping

End user group

End user groupTask 4

Failure modes for flood defences

Task 4

Failure modes for flood defences

Task 6

Breach models

Task 6

Breach models

Task 7

Reliability analysis for flood defences

Task 7

Reliability analysis for flood defences

Task 8

Inundation modelling

Task 8

Inundation modelling

Task 9

Socio-economic vulnerability assessment guidelines

Task 9

Socio-economic vulnerability assessment guidelines

Task 10

Multi-criteria risk assessment

Risk to life Model

Task 10

Multi-criteria risk assessment

Risk to life Model


Dissemination! Advisory board /contact group

Cooperation with local, regional and federal authorities and disaster management to consider the requirements of practical management, e.g. discussion of methods, evacuation planning: " 4 meetings: 2005 - 2007, " Final meeting 03/04 2008

! FLOODmaster coastal workshop" 2006, 2007 and 2008

! Publications" 4 book and journal articles, 12 conference contributions, 1

Master�s thesis


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EU Flood Directive

Preliminary risk assessmentPreliminary risk assessment

Flood hazard mapsFlood hazard maps

Flood risk mapsFlood risk maps

Risk management planRisk management plan

--

Inundation simulationInundation simulation

Risk analysis toolRisk analysis tool

Preliminary evacuation planningPreliminary evacuation planning



Lessons learned and future research

! Risk analysis is based on scenario approach (assumption of breach)

! Improvement of the vulnerability analysis! Transferability of Risk analysis tool to other

(coastal) sites! Application of the results in flood risk

management


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Task 27- German Bight Coast

Christian-Albrechts-University Kiel Horst Sterr, Gunilla Kaiser, Sonja Hofmann

LWI, TU BraunschweigAndreas Kortenhaus

E: [email protected]@geographie.uni-kiel.de

[email protected]


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Possible application:Evacuation planning


Evacuation planning (2)

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Vulnerable values


Standard 0,03 m/s1/3

0,015 m/s1/3

0,0225 m/s1/3

0,045 m/s1/3

0,06 m/s1/3

Inundation, sensitivity analysis

P1

P2

It is assumed that there is wave overtopping at P1and a dike breach at P2, both locations identified from a probabilistic hazard assessment

It is assumed that there is wave overtopping at P1and a dike breach at P2, both locations identified from a probabilistic hazard assessment

Variation of roughnessterms

Variation of roughnessterms

CAU Kiel Task 27 LWI Braunschweig German Bight Coast€¦ · Development of a modern risk analysis tool: integrated, transferable, micro-scale and probabilistic! Testing special parts

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