Post on 04-Jul-2020
Assessment of climate change induced Assessment of climate change induced
flood risk to buildingsflood risk to buildingsCity of London case studyCity of London case study
Slobodan P. Simonovic
ICLR and the University of Western Ontario
BackgroundBackground
• City of London supported project: Assessment of
infrastructure vulnerability to climate change
• Interdisciplinary team:
– Slobodan P. Simonovic, Professor (UWO, ICLR)– Slobodan P. Simonovic, Professor (UWO, ICLR)
– Donald H. Burn, Professor (UW)
– Dan Sandink, Manager (ICLR)
– Hyung-Il Eum, PostDoctoral Fellow (UWO)
– Angela Peck, MESc candidate (UWO)
– Lisa Bowering, MESc candidate (UWO)
– Dragan Sredojevic, MESc (UWO).
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Key MessagesKey Messages
• Urban environments and infrastructure are vulnerable to climate change
• Adaptation cost can be very high
• Adaptation = Risk management
• Comprehensive risk assessment methodology • Comprehensive risk assessment methodology is required to gather and examine available data in order to develop an understanding of the relevant climate effects and their interactions with municipal infrastructure
• Time to act is now
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Presentation OutlinePresentation Outline
• Methodology for the assessment of climate
change induced flood risk
– Climate modeling
– Hydrologic modeling– Hydrologic modeling
– Hydraulic modeling
– Risk assessment
• Case study – London, ON
• Conclusions
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MethodologyMethodology
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Risk Assessment
Hazard Analysis
Climate Modelling
Output: precipitation for four
climate scenarios
Hydrologic Modelling
Output: streamflows
Risk Index CalculationHydraulic Modelling Risk Index Calculation
Output: climate change flood
risk indices for all infrastructure
Infrastructure Ranking
Output: risk maps showing the
locations of high risk areas;
prioritized areas of high risk
Hydraulic Modelling
Output: water surface profiles
for climate scenarios
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MethodologyMethodology
• Hazard Analysis
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Risk Assessment
Hazard Analysis
Climate Modelling
Output: precipitation for four
climate scenarios
Hydrologic Modelling
Output: streamflows
Risk Index CalculationHydraulic Modelling Risk Index Calculation
Output: climate change flood
risk indices for all infrastructure
Infrastructure Ranking
Output: risk maps showing the
locations of high risk areas;
prioritized areas of high risk
Hydraulic Modelling
Output: water surface profiles
for climate scenarios
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Climate ScenariosClimate Scenarios
• Lower bound climate scenario
– The lowest extent of change
– Historical data, GCM and weather generator
• Upper bound climate scenario• Upper bound climate scenario
– The highest extent of change
– Historical data, GCM and weather generator
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Choice of GCMChoice of GCM
2.5
3.0
3.5
4.0
Pmean (2050s)
0.0
0.5
1.0
1.5
2.0
2.5
CS
IRO
Mk2
b_B
11_P
R
GIS
SE
-R_B
1_P
R
GIS
SE
-R_A
2_P
R
NC
AR
CC
SM
3_A
2_P
R
NC
AR
CC
SM
3_B
1_P
R
CS
IRO
MK
3_S
RA
1B_P
R
CS
IRO
MK
3_S
RB
1_P
R
NC
AR
CC
SM
3_A
1B_P
R
CG
CM
3T47
_PR
_B1
CS
IRO
MK
3_S
RA
2_P
R
CG
CM
3T47
_PR
_A1B
NC
AR
PC
M_A
1B_P
R
CG
CM
3T47
_PR
_A2
NC
AR
PC
M_A
2_P
R
GIS
SA
OM
_B1_
PR
MIR
OC
3.2_
ME
DR
ES
_A2…
MIR
OC
3.2_
ME
DR
ES
_A1…
GIS
SA
OM
_A1B
_PR
HA
DG
EM
1_A
1B_P
R
HA
DG
EM
1_A
2_P
R
EC
HO
-G_B
1_P
R
CG
CM
3T63
_PR
_A2
MIR
OC
3.2_
ME
DR
ES
_B1…
EC
HO
-G_A
2_P
R
CG
CM
3T63
_PR
_A1B
GF
DLC
M2.
1_B
1_P
R
CG
CM
3T63
_PR
_B1
GF
DL3
0_A
21_P
R
EC
HO
-G_A
1B_P
R
Mir
oc3
.2_H
IRE
S_B
1_P
R
GF
DLC
M2.
1_A
2_P
R
HA
DC
M3_
B1_
PR
GF
DLC
M2.
1_A
1B_P
R
CC
SR
NIE
S_B
21_P
R
HA
DC
M3_
A1B
_PR
HA
DC
M3_
A2_
PR
Mir
oc3
.2_H
IRE
S_A
1B_P
R
EC
HA
M5O
M_A
1B_P
R
EC
HA
M5O
M_B
1_P
R
EC
HA
M5O
M_A
2_P
R
Pre
c (m
m)
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Weather GeneratorWeather Generator
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Risk Assessment
Hazard Analysis
Climate Modelling
Output: precipitation for four
climate scenarios
Hydrologic Modelling
Output: streamflows
Risk Index CalculationHydraulic Modelling Risk Index Calculation
Output: climate change flood
risk indices for all infrastructure
Infrastructure Ranking
Output: risk maps showing the
locations of high risk areas;
prioritized areas of high risk
Hydraulic Modelling
Output: water surface profiles
for climate scenarios
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Hydrologic ModellingHydrologic Modelling
� Modification of HEC-HMS
� Nesting of sub-basins
� Medway (5 sub-basins)
� Stoney (6 sub-basins)
� Pottersburg (4 sub-basins)
Dingman (16 sub-basins)
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� Dingman (16 sub-basins)
1500
Hydrologic ModellingHydrologic Modelling
• Two hydrologic scenarios
– 100 year return period
– 250 year return period
0
300
600
900
1200
0 50 100 150 200 250
Peak Flow (m
3
/sec)
Return Periods
CC_LB
CC_UB
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Risk Assessment
Hazard Analysis
Climate Modelling
Output: precipitation for four
climate scenarios
Hydrologic Modelling
Output: streamflows
Risk Index CalculationHydraulic Modelling Risk Index Calculation
Output: climate change flood
risk indices for all infrastructure
Infrastructure Ranking
Output: risk maps showing the
locations of high risk areas;
prioritized areas of high risk
Hydraulic Modelling
Output: water surface profiles
for climate scenarios
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Hydraulic Hydraulic ModellingModelling
• HEC-RAS and HEC-GeoRAS
• Input: Streamflows from Streamflows from hydrologic model
• Output: floodplains to represent flood extent and depth for use in risk analysis
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Hydraulic Hydraulic ModellingModelling
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MethodologyMethodology
• Risk Assessment
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Risk Assessment Methodology Risk Assessment Methodology
Risk Indices
Consequences-Loss of Function
Flood Risk
Risk Tables
Risk Assessment
OutputProbability
Risk Indices-Loss of Function
-Loss of Equipment
-Loss of Structure
Flood Risk
Assessment due to
Climate Change
Risk Maps
Monetary Value-Loss of Function
-Loss of Equipment
-Loss of Structure
Probability of Hazard x Σ[Monetary Value x Consequence]
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Buildings– City
– Commercial, industrial,
institutional, residential
– More than 120,000
Data CollectionData Collection
Stage-Damage Curves– Ministry of Natural
Resources
– Research
Economic Data– Municipal Property Assessment Corporation
– City
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Spatial DataSpatial Data
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Infrastructure Flood ImpactInfrastructure Flood Impact
Infrastructure Potential Flood Effects
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Buildings Structure, contents, evacuation
Critical Facilities Structure, equipment/contents, delay in service, evacuation
Risk Index CalculationRisk Index Calculation
Risk Indices
Consequences-Loss of Function
Infrastructure Flood
Risk Tables
Risk Assessment
OutputProbability
Risk Indices-Loss of Function
-Loss of Equipment
-Loss of Structure
Infrastructure Flood
Risk Assessment due
to Climate Change
Risk Maps
Monetary Value-Loss of Function
-Loss of Equipment
-Loss of Structure
Probability of Hazard x Σ[Monetary Value x Consequence]
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Risk Index CalculationRisk Index Calculation
Probability - The likelihood that a particular flood event
will occur in a given year
CC_LB CC_UB CC_LB CC_UB
1:100yr 1:100yr 1:250yr 1:250yr
CC_LB CC_UB CC_LB CC_UB
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Risk Index CalculationRisk Index Calculation
Risk Indices
Consequences-Loss of Function
Infrastructure Flood
Risk Tables
Risk Assessment
OutputProbability
Risk Indices-Loss of Function
-Loss of Equipment
-Loss of Structure
Infrastructure Flood
Risk Assessment due
to Climate Change
Risk Maps
Monetary Value-Loss of Function
-Loss of Equipment
-Loss of Structure
Probability of Hazard x Σ[Monetary Value x Consequence]
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Risk Index CalculationRisk Index Calculation
Flood Consequence Multipliers
Loss of Function (IM1)
Loss of Equipment (IM2)
Loss of Structure (IM3)
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Floodplain
Aerial photo
Risk Index Calculation Risk Index Calculation
Aerial photo
Buildings
Identify inundated
buildings
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Stage-Damage Curves
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Risk Index CalculationRisk Index Calculation
Stage-Damage Curves
Single-storeySingle-storey
with basement
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(after Waters Edge, 2007)
Risk Index CalculationRisk Index Calculation
Deterministic (quantitative) and fuzzy
(qualitative) damage measures are combined
to describe loss of structure (IM3)
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Risk Index CalculationRisk Index Calculation
Risk Indices
Consequences-Loss of Function
Infrastructure Flood
Risk Tables
Risk Assessment
OutputProbability
Risk Indices-Loss of Function
-Loss of Equipment
-Loss of Structure
Infrastructure Flood
Risk Assessment due
to Climate Change
Risk Maps
Monetary Value-Loss of Function
-Loss of Equipment
-Loss of Structure
Probability of Hazard x Σ[Monetary Value x Consequence]
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Risk Index CalculationRisk Index Calculation
Monetary Value
The dollar value associated to a particular
building as a result of floodingbuilding as a result of flooding
D1 D2 D3
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Risk Index CalculationRisk Index Calculation
Risk Indices
Consequences-Loss of Function
Infrastructure Flood
Risk Tables
Risk Assessment
OutputProbability
Risk Indices-Loss of Function
-Loss of Equipment
-Loss of Structure
Infrastructure Flood
Risk Assessment due
to Climate Change
Risk Maps
Monetary Value-Loss of Function
-Loss of Equipment
-Loss of Structure
Probability of Hazard x Σ[Monetary Value x Consequence]
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Risk Index CalculationRisk Index Calculation
∑=
××=3
1
)(i
ikeikeke IMDPR
Rke = risk index
P = probability
D = monetary value
IMike = impact multiplier
k = building type
e = building element
i = impact category
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Case Study Case Study –– London, ONLondon, ON
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ResultsResults
Risk Indices
Consequences-Loss of Function
Infrastructure Flood
Risk Tables
Risk Assessment
OutputProbability
Risk Indices-Loss of Function
-Loss of Equipment
-Loss of Structure
Infrastructure Flood
Risk Assessment due
to Climate Change
Risk Maps
Monetary Value-Loss of Function
-Loss of Equipment
-Loss of Structure
Probability of Hazard x Σ[Monetary Value x Consequence]
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ResultsResults
• Table and map for each of the 4 climate
scenarios + 1 for the current state:
100 CC_LB 250 CC_LB 250 UTRCA
100 CC_UB 250 CC_UB100 CC_UB 250 CC_UB
• Areas of high risk within each scenario
individually
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ResultsResults
Scenario Area(km2)
Buildings Critical Facilities
100 CC_LB 22.95 1110 3
Infrastructure affected
100 CC_UB 25.79 2535 6
250 CC_LB 25.95 2517 6
250 CC_UB 27.87 2706 6
250 UTRCA 24.56 1762 3
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ResultsResults
Table Layers Map
Cell DA RI
C3 0326 0.17
Reference
Cells
100 CC_LB Scenario
C3 0326 0.17
C3/C4 0550 0.28
B3/B4 0677 0.49Dissemination
Areas
Risk Index
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ResultsResults100 CC_LB scenario100 CC_LB scenario
DA 0035
2nd highest risk
Broughdale dyke
DA 0092
Highest risk
Pottersburg Creek culvert
DA 0890
3rd highest risk
The Coves
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ResultsResults100 CC_UB scenario100 CC_UB scenario
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ResultsResults250 CC_LB scenario250 CC_LB scenario
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ResultsResults250 CC_UB scenario250 CC_UB scenario
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Comparison AnalysesComparison Analyses
Five analyses:
(1) Climate change impact250 UTRCA vs. 250 CC_UB
(2) CC uncertainty - comparison of 100 year climate events100 CC_LB vs. 100 CC_UB100 CC_LB vs. 100 CC_UB
(3) CC uncertainty - comparison of 250 year climate events250 CC_LB vs. 250 CC_UB
(4) Regulatory flood - comparison of lower bound scenarios100 CC_LB vs. 250 CC_LB
(5) Regulatory flood - comparison of upper bound scenarios100 CC_UB vs. 250 CC_UB
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Comparison AnalysesComparison Analyses
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Comparison AnalysesComparison Analyses
Areas of interest include:
• Cells B5/C4: Along Pottersburg Creek, north of Trafalgar to the airport
• Cell C3: Forks of Thames River• Cell C3: Forks of Thames River
• Cells E3/E4 & D4/D5: Dingman Creek
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Comparison AnalysesComparison Analyses
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Comparison AnalysesComparison Analyses
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Comparison AnalysesComparison Analyses
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Key MessagesKey Messages
• Urban environments and infrastructure are vulnerable to climate change
• Adaptation cost can be very high
• Adaptation = Risk management
• Comprehensive risk assessment methodology is • Comprehensive risk assessment methodology is required to gather and examine available data in order to develop an understanding of the relevant climate effects and their interactions with municipal infrastructure
• Time to act is now
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ResourcesResources
www.slobodansimonovic.comwww.slobodansimonovic.comwww.slobodansimonovic.comwww.slobodansimonovic.com
Research -> FIDS -> Projects
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