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Introduction to the disaster risk profile of Khulna
iPrepare Campaign Asian Disaster Preparedness Center (ADPC)
10 September 2014, Khulna University, Bangladesh
Mustafa Saroar, PhDProfessor of Urban & Rural Planning
Khulna University, Khulna 9208, Bangladesh
Website: http://kuurp.ac.bd/mustafa.htmlemail: [email protected]
I. Important Concepts
Disaster Vs Hazard: (Mis)conception !!!
3
• Disaster
A serious disruption of the functioning of a community or a society causing widespread human, material, economic, or environmental losses which exceed the ability of the affected community or society to cope using its own resources (UNISDR, 2004).
Hazards
• A hazard is a rare or extreme event in the natural or human-made environment that has the potential to adversely affect human life, property or activity to the extent of causing a disaster.
Natural Hazards & Unnatural Disasters !!!
4
Natural Hazard but Unnatural Disaster:• Without hazards, there is no disaster (and therefore
no disaster risk), even if people are vulnerable.
• Without people being vulnerable there won´t be a
disaster even in extremely hazard-prone regions.
Standardizing the Term- Disaster?
5
• Disaster (Quantitative Criteria of EMDAT)
At least one of the following criteria must be fulfilled:
• Ten (10) or more people reported killed.• Hundred (100) or more people reported affected.• Declaration of a state of emergency.• Call for international assistance.
Common Elements ofDisasters:
• Damage of …..
• Disruption….
• Distress …..
Typology of Hazards
6
• Criteria for categorization of Hazards)
• 1. Length of forewarning
• 2. Magnitude of impact
• 3. Geographical scope of impact
• 4. Duration of impact
• 5. Speed of onset
Natural Hazards
Meteorological
Topographical
Environmental
Man-made Hazards
Technological
Industrial accidents
Security related
Hazard Types
7
• Sudden onset (geological and climatic hazards): Earthquakes, Tsunamis, Floods, Tropical storms, Volcanic eruptions, Landslides.
• Slow onset (environmental hazards): Drought, Famine, Environmental degradation, desertification, Deforestation, Pest infestation.
• Industrial/Technological: System failures/accidents, Spillages, Explosions, Fires.
• War and civil strife: Armed aggression, Insurgency, Terrorism and other actions leading to displaced persons and refugees.
• Epidemic: Water and/or food-borne diseases, persons-to-persons diseases (conduct and respiratory spread), vector-borne diseases.
Risk
8
Risk. The probability that negative consequences
may arise when hazards interact with vulnerable
areas, people, property and environment.
Risk assessment is an attempt to anticipate what
will happen in the future…
Risk = Hazard X Vulnerability
The highest risk can be found in regions where both
hazards and vulnerabilities are most elevated.
Vulnerability
9
Vulnerability: A concept which describes factors or
constraints of an economic, social, physical or
geographic nature, which reduce the ability of a
community to prepare for and cope with the impact of
hazards.
Vulnerability = Exposure + Fragility/Sensitivity) +
(lack of) Resilience/Adaptive capacity
Analyzing Exposure
Exposure: Am I in the firing line!!!
Supposed there are two families in the same hazard zone, e.g. a cyclone affected region. The cyclone goes along with destructive winds coming from the sea.
One family lives behind a dense and solid barrier of grown-up trees, whereas the other family does not have this kind of protection. So, family behind the tree barrier is less exposed to cyclones than the other family.
10
Analyzing Exposure- An Example
11
Exposure scoring
Household with all its assets in high-hazard
zones (e.g. all arable lands, in high hazard
zone) ; no favorable topographic condition
Score: 3
Households with major assets in high-
hazard, some in low or non hazard zones
(e.g. most of the land resources in high hazard
zone, but some small field in low or non –
hazard zones); slightly favorable
topographic conditions – above average
Score: 2
Households with significant assets in low
or non-hazard zones (e.g. half of land
resources in low or non-hazard zones);
favorable topographic conditions-high
above average
Score: 1
Analyzing Sensitivity
Fragility/Sensitivity: Do I have Bullet proof Jacket!!!
Supposed there are two families in the same hazard zone, e.g. a cyclone affected region. The cyclone goes along with destructive winds coming from the sea.
One family lives in concrete made house and other one on mud house. So, sensitivity/fragility of family living in mud house is more than the other family.
12
Analyzing Adaptive Capacity
Resilience/Adaptive Capacity: Can I run away very fast!!!! Or I can fight back!!!
I define resilience or capacity mainly in the sense of “coping capacity” to overcome a disaster (So, this parameter has strong links to economic resources, skills and knowledge to be found on a family/household level.
One family has regular source of income and other one do not have. So, family adaptive capacity is high for family that has regular source of income.
13
14
Disaster Risk Profile• Snapshot of all the risks a target human system is subject towithin a given timeframe.
• Simple risk profile includes a set of hazard scenarios, potentiallosses, and the probability of occurrence
• More comprehensive risk profile includes:- categorization of risks, impacts of risks, relative priority of the risks, acceptable levels of risk- linkages between different levels of risks, ways of measuringthe risk (qualitative and quantitative), key risk areas/hotspots- Risk reduction measures, capacity for risk treatment, learningneeds and tools, etc
Disaster Risk Profiling
Why do we need Disaster Risk Profiling: Some Examples
Just imagine you are involved in a project
constructing new houses or installing irrigation
schemes without paying attention to hazards.
Sooner or later the houses or canals could be damaged
by such hazards and you would be held responsible for
not sufficiently addressing extreme natural events.
Another example could be the distribution of salt-
tolerant or drought-tolerant seed, for which you have to
know which farmers´ fields are particularly exposed to
drought or salinity in order to calculate how much seed is needed.
15
16
Use of Disaster Risk Profile
Disaster Risk Profile
Risk Assessment
Risk Reduction Planning
Implementation of Risk Plan
Monitoring & Evaluation
DRR Plan
Early Warning Plan
Contingency plan
17
II Disaster Risk Profile of Khulna
Why should we care about Disasters?
18
Why should we care about Disasters?
19
GBM Delta: A Climate Hotspot…
Climate change will impinge on the sustainable development of most developing countries of Asia-Pacific including Bangladesh
The Most
vulnerable
states ……
20
Along BD Coast: 1.5 m rise by 2100.
Bangladesh Today: Without SLR effects
Bangladesh in 2100: With SLR effects
BD Rank 1:
A 1-meter rise could normally inundate 24 million;
If precipitation increases 15% the affected pop would be 71 million (Nicholls, 1995; Nicholls et al. 1995);
No. of affected would increase as 130 m more people would be added by 2100(IPCC, 2007).
21
Population at Risk from HM-Disasters
With 1 meter SLR by 2100 (Ali, 1999).
BD Coastal Zone:
The coastal region: 36,000 km2, some 700 km coast line. 3 distinct parts: South-western, central, and eastern.
The South-western part- the Ganges tidal plain, comprises the semi-active delta. The central region- the GBM river system discharges into the Bay of Bengal. The eastern region- the longest beaches in the world. The South -western Region is more vulnerable (Ortiz, 1994; RVCC, 2003; Schaerer & Ahmed, 2004).
South-western Central Zone Eastern Zone
22
Disaster Risk Assessment: Coastal Khulna
Coastal boundary and Existing Risk Zones
19 Coastal Districts
Higher threat from SLR Impacts:Patuakhali,Barguna, Khulna, Bagerhat District (Ortiz, 1994) Bagerhat
Khulna
Satkhira
23
Khulna Region: Most Prone to HM-Disasters
General Characteristics of Coastal Khulna Deltaic plain , tidal river, coastal morphology
Agriculture & Allied Occupations
Heavily dependent on Aman…but declined- Aman; Sporadic Boro…
80s onwards: Shrimp production; Change in Livelihood & Food security
Food production increased 3 times; one third population are food insecure.
HM Disasters- formidable challenge for livelihood security 24
With 1 meter SLR by 2100 (Ali, 1999).
South-western
HM Disasters in Coastal Khulna
25
Area Impacts of HM Disasters
Khulna Dist: Salinity Water logging/Flood
Drought Cyclone/Surge
Phultala Low High Low Medium
Dumuria Medium High Low High
Batiaghata High Medium Medium High
Dacope Very High High High Very high
Paikgacha Medium Medium Medium High
Jessore Dist:
Monirampur Medium Very High Low Medium
Keshabpur Medium Very High Low Medium
Abhoynagar Medium Very High Low Medium
HM Disasters in Coastal Khulna
26
Area Impacts of HM Disasters
Satkhira Dist: Salinity Water logging/Flood
Drought Cyclone/Surge
Kaliganj Very High Very High Medium Very High
Asasuni Very High Medium High Very High
Koyra Very High High Very High Very High
Shymnagar Very High High Very High Very high
Debhata High Medium Medium High
Bagerhat Dist:
Sharankhula Very High High Very High Very High
Mongla Very High High High Very High
Rampal High High Medium High
Impacts of HM Disasters on Livelihood
27
Jan/Pou Feb/Mag Mar/Fal Apr/Cho May/Boi Jun/Jus Jul/Ash Aug/Shr Sep/Vdr Oct/Ars Nov/Kar Dec/Augr
Drought
Cyclone
Flood
Salinity
Aman
IRRI
Fry
Crab
Hilsha
28
Physical Infrastructures Impacts of HM Disasters
Salinity Flood/Water logging
Drought Cyclone/Surge
Embankment, Polders, Dykes, Sluice gates, Canals
Low High Medium Very High
Cyclone & flood shelters Low High Medium Very High
Water supply, drainage, &source of potable water
Very High Very high Medium Very High
Hat, Market places, schools, & other community infrastructures
Low High Medium Very high
Roads, Bridges, Landing station (Ghat)
Medium Very high Medium Very high
Impacts of HM Disasters on Infrastructures
Water Logging- The Major Challenge Massive Flood in 1954 and 1956
UN- Krug Mission Report for Construction of Polders
From 1960s: About 30 polders and 1550 Km Embankment
Until 80s protected intrusion of salinity & surge
Massive water logging: Subsidence of soil inside polder & massive siltation outside the polder area.
29
30
A significant part of this entire area is water logged for decades-A Development Disaster
Production of rice and other crops are restricted
Massive occupational transformation
31
Changes in Hydro-geomorphology lead to Water Logging: An Example
32
Changes in Hydro-geomorphology lead to Water Logging: An Example
33
Water Logging: Rooftop School ???
34
Water Logging: How safe is Khulna City???
Water logging scenario of Khulna City Source: IWM (2010)
35
Salinity Intrusion
Salinity Intrusion in
Soil, Surface Water bodies, and below ground aquifer
36
Salinity Intrusion
Some pockets
are worst affected by high salinity caused by tidal action and on purpose ingression of salt water for shrimp culture
Areas likely to be affected by SLR (5ppt Salinity as Proxy)
Saline zone is moving further inland from the coast line.
NAPA accepted IPCC’s projection of 88 cm SLR by 2100 along BD coast (NAPA 2005)
37
Shift of Saline Zone
38
Salinity Intrusion
District 1-4 dSm-1) (4-8 dSm-1) (8-16 dSm-1) (>16 dSm-1) Total Satkhira 16.50 85.60 10.90 10.90 146.35 Khulna 3.90 92.54 13.80 9.80 120.04 Baaerhat 28.30 77.08 2.60 0 107.98
39
Salinity situation in Khulna City: Bad Too!!!
130 m
300 m
KhulnaTown Bhairab River
Deepaquifer Brackish
water
Fresh-
brackish
water
interface
Brackish water Shallow aquifer
Clay/silt
Freshwater
West East
Schematic East-West Section through Khulna City.
Source: Interim Report, KDA, 1998.
40
Date
Maximum
Wind speed
(km/hr)
Storm Surge
height (metres)Death Toll
11 May 1965 161 3.7-7.6 19,279
15 December 1965 217 2.4-3.6 873
01 October 1966 139 6.0-6.7 850
12 November 1970 224 6.0-10.0 300,000
25 May 1985 154 3.0-4.6 11,069
29 April 1991 225 6.0-7.6 138,882
19 May 1997 232 3.1-4.6 155
15 November 2007 223 -- 3363
25 May (AILA) 2009 92 -- 190
Major Cyclones In Bangladesh
41
Year of Cyclone Hit Khulna
1909: 16 Oct About 1000
1917:24 Sept About 500
1942: Oct N/A
1961: 9 May About 12000
1966: 1 Oct About 1000
1970: 12 Nov About 300000
1971:28-30 Nov
1973:6-9 Dec
1974:13-15 Aug
1975: 9-12 May
1985: 24-25 May
1986:8-9 Nov
1991: 29 April About 150000
1998: 19-20 Nov
2007: 15 Nov
2009: May
42
Cyclone & Surges
43
Base
condition
Year
2030
Increase
From
base
condition
Year
2050
Increase
From base
condition
Year
2080
Increase
From base
conditioon
Storm
Surge
Height, m
5.5 6.7 1.2 7.5 2 8.3 2.8
Surge Height Will be More
44
More Area Will be Inundated
45
Localized Erosion
46
Drought/Dryer Condition
Might raise the level of water at the mouth (estuary) of a river; Backwater Effects; More area under inundation in July-Sept; Gradual permanent inundation with higher depth and length of time
Coastal Inundation
Storm Surge
The rise in SST may increase the frequency and intensity of cyclones (Ali 1996; Mohanti 1990);
Increased intensity is confirmed, however, frequency yet to be.
Salinity Intrusion
Cyclonic event
In three fronts: surface water, groundwater and soil; 5 ppt saline front may penetrate about 40 km inland [from present 120-160 km from coast]; Approx. 16000 sq. km. will be affected & 1000 sq. km. severely
Shoreline will retreat 18 km inland & impacts of cyclonic storm surge will normally be felt further inland;
Surge height might increase 13 to 46% for SLR of 0.3 m and 1 m (Ali,
1999).
Summary of Effects of HM Disasters in Khulna
HM Disasters: A Threat Multiplier for Coastal Khulna
Baseline Pressures
• Extreme poverty•Poor or no maintenance of Embankments, Dykes, Polders, Sluice gates
•Illegal encroachment of natural drainage-canal system
• Extensive use of Cyclone shelter, Market Infrastructure
HM Disaster induced Pressures
•Increasing erosion & bleaching of these structure (Wind & water force induced)
• Heavy siltation, and poor drainage capacity cause both water logging and trapping of saline water
•Intensified cyclones, surges,torrential rainfall damage the usability and make unsuitable for uses.
Infrastructure
damage &
disrupted life
Increased burden
on household
community & state
. Spend more time
to supplement
income
Unsustainable
coping strategies:
i.e. migration; conflict
HM
Disasters:
Cyclone,
surge, flood
Example of
exacerbated cycle
of poverty due to
HM Disasters
HM Disaster might induce huge in migration to Khulna City
Hu
ge in
flu
x o
f D
isp
lace
d P
ers
on
Shall we wait for…
Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation
(Agenda 21)
Only way to follow:Precautionary Principle