2010_2t_nhra
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1 | NHRA Progress Report July-August 2010
This Progress report is submitted by ADPC to the World Bank & MOHA to highlight the progress in the execution of Nepal Hazard Risk Assessment (NHRA) project as a part of the project deliverables.
Methodology for Hazard and Risk Assessment The overall methodology for the project has been presented in the flowchart shown in figure 1.
Figure 1: Flowchart showing methodology of the project
ACTIVITIES CARRIED OUT AND COMPLETED
1. Hazard Assessment The Hazard and susceptibility modeling and mapping for five major hazards including earthquake, Floods, Landslides, Epidemics and drought has been carried. The modeling and mapping has been carried out based on well established technical and scientific methods. The details are as below:
a. Earthquake Hazard Assessment
Earthquake hazard assessment has been carried out based on Modified Mercalli Intensity Scale. The Peak Ground Acceleration map developed by Department of Mines and Geology has formed the basis for earthquake zoning. The attenuation relationship has been developed based on Trifunac (Trifunac and Brady, 1975). Other methods like Wald (Wald et al., 1999) and Probabilistic seismic Hazard Assessment Map (PSHA) have been compared with developed hazard map, validated and finalized. The study proposes three zones of earthquake namely Very High,,High,
Nepal Hazard Risk Assessment
Progress Report July-August 2010
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2 | NHRA Progress Report July-August 2010
and Medium severity. The zoning map has been prepared for various return period i.e, 50 years, 100 years, 250 years and 500 years. The maps are shown in figure 2.
Figure 2: Earthquake hazard maps for various return period (Daft Version)
b. Landslide Hazard Assessment
The developed landslide hazard maps are classified into rainfall and earthquake induced landslide hazard. Landslide hazard, defined as the annual probability of occurrence of a potentially destructive landslide event, was estimated by an appropriate combination of the triggering factors (mainly extreme precipitation and seismicity) and susceptibility factors (slope, lithology, and soil moisture). The weights of different triggering and susceptibility factors were calibrated to the information available in landslide inventories and physical processes. The general approach used in the present study is a modified and improved version of the approach used by Nadim et al. (2006). The landslide hazard maps are categorized into high, medium, low, and negligible severity. The landslide hazards maps are shown in Figure 3(a, b).
Figure 3(a,b): Landslide Hazard Maps: Rainfall and earthquake triggering factors(Daft Version)
c. Flood Hazard Assessment
Floods are regular phenomenon and affects broadly central and southern region of Nepal. There are several perennial rivers, contributing regular floods like Bagmati, Rapti, Kamala, Kankai, Tinau, Karnali, Babai and Narayani etc. These rivers are contributing major losses to life and other economic sectors. The study aims to carry out desktop based flood hazard assessment for selected rivers. The hazard assessment has resulted in defining inundation area and depth using one dimension model namely HECRAS. The Flood scenario has been developed for various return periods of 10 years, 25 years, 50 years, 100 years and 500 years. The flood hazard assessment is further cross checked with established and official data and information. A national level
technical team is also been consulted while finalizing the flood hazard assessment maps. A flood hazard map for Rapti River basin has been shown in Figure 4(a, b, c, d & e).
Figure 4: Flood Hazard Assessment for Rapti River Basin(Daft Version)
d. Drought Hazard Assessment
In recent past, drought has been frequent occurring disasters in the country. Due to climate changes, rapid degradation of environment and exploitation of natural resources, the drought situation has been aggravated. The drought hazard assessment has been carried out using well established tools i.e. Standard Precipitation Index (SPI) and Soil Moisture Index (SMI). The drought susceptibility map has been shown in Figure 5.
Figure5 Moderate drought susceptibility maps for (a) Winter (b) Premonsoon (c) Monsoon and (d) Postmonsoon seasons (Daft Version)
e. Epidemics Hazard Assessment
The health hazards is classified as diseases and outbreaks. The health hazard mapping include Diarrhoea, Kalazaar, Hepatitis, Influenza, Typhoid, Acute Respiratory Infection, Malaria, Sexual Transmitted Infection, Filariasis, Gastroentri Tuberculosis, and Leprosy. For each disease and outbreak, Incidence index have been developed. Further trend analysis has been carried out to understand severity of the problems. The disease susceptibility maps are shown in figure 6.
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3 | NHRA Progress Report July-August 2010
Figure 6: Map showing disease ad out break susceptibility (Daft Version)
2. Exposure Assessment In the project, Exposure(UN/ISDR 2009) is defined as People, property, systems, or other elements present in hazard zones that are thereby subject to potential losses The important sectors, contributing to the economy has been considered for exposure and vulnerability assessment. The major sectors including housing, education, health, transportation, agriculture, industry, Irrigation infrastructure, power, tourism, trade and power has been considered for exposure assessment. The exposure analysis has been carried out for all five types of hazards.
3. Vulnerability and Risk Assessment a. Earthquake Vulnerability and Risk Assessment Project scopes for earthquake vulnerability assessment of various priority sectors. For study purpose two scenarios are considered I.e. 500 years and 50 years return period. For each hazard scenario, vulnerability assessment has been carried out considering sectors including Housing, Education, Health, Transportation, Tourism, Power and Irrigation. The methodology includes collection of physical infrastructure data, reclassification of building and infrastructure type suit to vulnerability modelling, hazard exposure analysis, define vulnerability criteria and establish vulnerability assessment matrix. The Vulnerability is further characterised by setting up fragility functions as shown in Figure 7. The direct cost of damage to various sectors for various severity has been calculated.
b. Flood Vulnerability and Risk Assessment The Flood vulnerability assessment has been carried out for specified sectors including agriculture, housing, health, education, industry, transportation, fishing and tourism. The methodology for Vulnerability assessment has been established based on expert opinion of disaster management experts and hydrological modelling experts. The damage depth has been developed for floods. The details are shown in Figure 8. The direct cost of damage has been calculated based on depth damage ratio. Figure 9 shows the approach for flood vulnerability and risk assessment for agriculture sector.
Very High Seismic hazard Zone High Seismic Hazard Zone
Name of
District
Type A
(Mud
/Adobe0
Type B
(Brick /
Stone)
Type C (Timber
/ RCC)
Type A Type B Type C
X 2345 5643 9845 -- -- --
Y 1234 4325 2314 -- -- --
Z 1236 4336 9753 --- ---- ----
Very High Seismic hazard Zone High Seismic Hazard Zone
Name of
District
Type A
(Mud
/Adobe0
Type B
(Brick /
Stone)
Type C (Timber
/ RCC)
Type A Type B Type C
X 2345 5643 9845 -- -- --
Y 1234 4325 2314 -- -- --
Z 1236 4336 9753 --- ---- ----
S.
N
o
Type of
Building
Number
of
houses
Number of Houses / Assets
Intensity VI Intensit
y
VII
Intensit
y
VIII
Intensit
y
IX1 Type A 2345 D1
D2
D3
D4
D1
D2
D3
D4
D1
D2
D3
D4
D1
D2 118
D3 1054
D4 1173
2 Type B 5643 D1
D2
D3
D4
D1
D2
D3
D4
D1
D2
D3
D4
D1 283
D2 2255
D3 2822
D4 283
3 Type C 9845 D1
D2
D3
D4
D1
D2
D3
D4
D1
D2
D3
D4
D1 4429
D2 4923
D3 493
D4 ---
D1 Minor Cracks, D2 Large cracks, D3 partial collapse & D4 Complete
collapse
S.
N
o
Type of
Building
Number
of
houses
Number of Houses / Assets
Intensity VI Intensit
y
VII
Intensit
y
VIII
Intensit
y
IX1 Type A 2345 D1
D2
D3
D4
D1
D2
D3
D4
D1
D2
D3
D4
D1
D2 118
D3 1054
D4 1173
2 Type B 5643 D1
D2
D3
D4
D1
D2
D3
D4
D1
D2
D3
D4
D1 283
D2 2255
D3 2822
D4 283
3 Type C 9845 D1
D2
D3
D4
D1
D2
D3
D4
D1
D2
D3
D4
D1 4429
D2 4923
D3 493
D4 ---
D1 Minor Cracks, D2 Large cracks, D3 partial collapse & D4 Complete
collapse
Y-A
xis
X-Axis
V VI VII VIII IX X
100
90
80
70
60
50
40
30
20
10
Da
ma
ge
Ra
tio
Earthquake Intensity - MMI
Y-A
xis
Damage Ratio = Cost of Damage /
Replacement Cost
X-Axis
Exposure of Housing SectorVulnerability Factors
Vulnerability Matrix
Figure 7: Flowchart showing vulnerability and risk assessment for earthquake
Figure 8: Flowchart showing the methodology for Flood vulnerability and risk assessment
Figure 9: Flowchart showing the methodology for vulnerability and risk assessment for Agriculture sector
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4 | NHRA Progress Report July-August 2010
c. Landslide Vulnerability and Risk Assessment The landslide largely affects transportation, housing and agriculture sectors. Landslide is affecting the community at local level, but it disconnects several part of the country to the commercial and necessary facility areas. This leads to indirect losses. The damage occurs is negligible compare to national scale
Disaster loses. The aspects of indirect damage cost have been incorporated in economic modelling. d. Drought Vulnerability and Risk Assessment The drought largely affects the crops and agriculture. In this regard, only agriculture sector has been considered. The methodology for agriculture vulnerability and risk assessment is shown below in Figure 10.
Drought Vulnerability & Risk Assessment (Agriculture)
Extreme Drought Impact on Crops
40
45
50
55
60
65
70
75
High-Hill Mid-Hill Terai
Region
Es
tim
atio
n o
f L
os
se
s
Impact of w inter drought on w heat and barley
Impact of pre-monsoon drought on w heat and barley
Impact of monsoon drought on paddy and maize
Impact of post-monsoon drought on paddy
Severe Drought impacts on Crops
30
35
40
45
50
55
60
65
70
High-Hill Mid-Hill Terai
Severe drought
Region
Es
tim
ate
d L
os
se
s i
n p
erc
en
ta
ge
Impact of w inter drought on w heat and barley
Impact of pre-monsoon drought on w heat and barley
Impact of monsoon drought on paddy and maize
Impact of post-monsoon drought on paddy
Moderate Drought impacts on Crops
10
15
20
25
30
35
40
High-Hill Mid-Hill Terai
Moderate drought
Region
Es
tim
ate
lo
ss
es
in
pe
rc
en
tag
e
Impact of w inter drought on w heat and barley
Impact of pre-monsoon drought on w heat and barley
Impact of monsoon drought on paddy and maize
Impact of post-monsoon drought on paddy
Extreme Drought Impact on Crops
40
45
50
55
60
65
70
75
High-Hill Mid-Hill Terai
Region
Es
tim
atio
n o
f L
os
se
s
Impact of w inter drought on w heat and barley
Impact of pre-monsoon drought on w heat and barley
Impact of monsoon drought on paddy and maize
Impact of post-monsoon drought on paddy
Severe Drought impacts on Crops
30
35
40
45
50
55
60
65
70
High-Hill Mid-Hill Terai
Severe drought
Region
Es
tim
ate
d L
os
se
s i
n p
erc
en
ta
ge
Impact of w inter drought on w heat and barley
Impact of pre-monsoon drought on w heat and barley
Impact of monsoon drought on paddy and maize
Impact of post-monsoon drought on paddy
Moderate Drought impacts on Crops
10
15
20
25
30
35
40
High-Hill Mid-Hill Terai
Moderate drought
Region
Es
tim
ate
lo
ss
es
in
pe
rc
en
tag
e
Impact of w inter drought on w heat and barley
Impact of pre-monsoon drought on w heat and barley
Impact of monsoon drought on paddy and maize
Impact of post-monsoon drought on paddy
8,00511,90013,00016,010Far Western
8,00511,90013,00016,010Mid Western
8,54013,57016,00017,080Western
8,92512,87014,85017,850Central
9,61012,01014,14019,220Eastern
BarleyMaizePaddyWheatRegion
Price (Rs/mt)
Price of commodities in the nearest terai market
8,00511,90013,00016,010Far Western
8,00511,90013,00016,010Mid Western
8,54013,57016,00017,080Western
8,92512,87014,85017,850Central
9,61012,01014,14019,220Eastern
BarleyMaizePaddyWheatRegion
Price (Rs/mt)
Price of commodities in the nearest terai market
Exposure on Agriculture
Vulnerability function
for crops
Estimation of Loss in crop production due to various intensities of drought
Area Affected
Define Seasons
Crop Consideration
Drought Category
Probability of Drought
Cropping Calendar
Loss coefficients
Barley
Wheat
Maize
Paddy
TeraiMid hillHigh hill
Yield mt/ha
Crop and region
Crop Yield
Barley
Wheat
Maize
Paddy
TeraiMid hillHigh hill
Yield mt/ha
Crop and region
Crop Yield
Agriculture YieldMarket Price
Exposure on Agriculture
Vulnerability function
for crops
Estimation of Loss in crop production due to various intensities of drought
Area Affected
Define Seasons
Crop Consideration
Drought Category
Probability of Drought
Cropping Calendar
Loss coefficients
Barley
Wheat
Maize
Paddy
TeraiMid hillHigh hill
Yield mt/ha
Crop and region
Crop Yield
Barley
Wheat
Maize
Paddy
TeraiMid hillHigh hill
Yield mt/ha
Crop and region
Crop Yield
Agriculture YieldMarket Price
Figure 10: flowchart showing methodology for drought assessment e. Epidemic Vulnerability and Risk Assessment The population has been considered for epidemic vulnerability assessment. Quantification of number of people susceptible to epidemics are estimated, however the losses are not quantified in terms of money.
ONGOING ACTIVITIES
4. Assessment of Economic Risk The economic risk assessment will be developed based on IIASAs CATSIM model. The CATSIM model will be applied to estimate the expected losses caused by various hazards. This will result in direct impacts and indirect losses. The approach for risk assessment defines five steps including assessment of direct and asset risk, estimation of fiscal vulnerability, fiscal gaps, mainstreaming disaster risk and development planning and assessing options and risk transfer options. The model further uses SAM approach for assessing multiplier effect on various sectors due to disasters. The process has been represented in flowchart which may be referred at Figure 11.
FUTURE ACTIVITIES
5. Recommendations for Prioritizing the Mitigation Investments Based on hazard, vulnerability & economic risk assessment and interaction with focal national government agencies, the recommendations will be prepared for prioritizing disaster risk mitigation and associated investments.
This report was prepared by Project team Urban Disaster Risk Management (UDRM) Asian Disaster Preparedness Center www.adpc.net July-August 2010
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5 | NHRA Progress Report July-August 2010
Step 1:
Assessment of Direct
and Asset Risk
(CATSIM)
0.94
0.95
0.96
0.97
0.98
0.99
1
0 5 10 15 20 25 30
Asset losses (%GDP)
Flood
Joint
EQ
Damage-frequency distribution for EQ, flood and joint damage distribution
20 year
50 year
500 year100 year
Step 2:
Estimation of Fiscal
Vulnerability
Step 3:
Estimation of Fiscal
Vulnerability & Fiscal
Gap
Step 4:
Mainstreaming
disaster risk and
development planning
Step 5:
Assessing options for
reducing and transfer
disaster risk
SAM Approach
Assessing Multiplier
Effect
Primary loss for each industrial sector
GDP loss
Divided proportionally according to scale of activity of each industrial sector
Change in final demand
Dividing the changes in output by the diagonal term of the multiplier matrix
Loss for each sector(Higher order effect)
Multiplied by Multiplier matrix
Income impact for households
20 year event 50 year event 100 year event 500 year event0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
Los
s of
Gov
ern
ment
(bn U
SD
)
AidDiversionIDA debtFinancing gap
Fiscal vulnerability and fiscal gap for the joint risk distribution
Fiscal gap: reconstruction and relief can only be
done partially: Households do not get
compensated and infrastructure not
replaced
Leads to economic losses in terms of
GDP and income (also debt uptake effect
accounted for)
Parameters of the production function
Coefficient
S.E t value P-value
Constant 4.64 2.02 2.30 0.032
Capital 0.46 0.06 7.15 0.0000004
Labor 0.60 0.20 3.00 0.006524
Coefficient
S.E t value P-value
Constant 4.64 2.02 2.30 0.032
Capital 0.46 0.06 7.15 0.0000004
Labor 0.60 0.20 3.00 0.006524
R square : 0.996
2 3 4 5 6 7 8 9 100.72
0.74
0.76
0.78
0.8
0.82
0.84
Year
Reve
nue su
btracted
deb
t rep
ayme
nt (b
n US
D) Simulated fiscal impacts over next 10
years when accounting for disaster risk
and financial vulnerability
1 2 3 4 5 6 7 8 9 107.2
7.4
7.6
7.8
8
8.2
8.4
8.6
Year
GDP
(bn
USD
)
Simulated GDP impacts over next
10 years
No event
Some events
No event
Some events
Economic Risk
Assessment
Figure 11: Flowchart showing process of economic risk assessment