1. Establishing Basic Parameters: Risk Assessment
Session 2
World Bank Institute
Risk Sensitive Land Use Planning

2. Risk Assessment: Concepts and Definitions
Probability/likelihood of loss due to one or more hazard events in pre-defined geographical area
Depends on severity of hazard, vulnerability of exposed assets and the capacity to cope with risk
Includes time dimension or frequency of occurrence of hazards
Risk Assessment
Analysis of both the severity of hazard and vulnerability of assets in a particular location
Could include a time-dependent dimension
Can be undertaken at various levels of precision
Provides input to planning strategies
Risk Sensitive Land Use Planning

3. Risk Sensitive Land Use Planning
Risk Assessment: The Process
Process to determine severity and spatial distribution of risk
Analytical tool for disaster risk reduction
Basis for land use planning interventions
Risk
Assessment
Vulnerability
Hazard
Assets at
Capacity
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4. Risk Sensitive Land Use Planning
Risk Assessment: Initial Decisions
Precision of data
Relatively rough information sufficient for public information and commitment building
Greater levels of precision required to justify differential treatment of land
Increasing precision increases the cost of assessment
Time-related factors
Recurrence interval of extreme events
Current land use practices or future risks associated with alternative land use scenarios
Depth of assessment
Hazard analysis defines the spatial scale of the hazard and also generates commitment to public policy initiatives
Vulnerability analysis helps to understand the consequences of alternative land use configurations
Probabilistic risk analysis captures the full range of potential casualty and damage experiences for a rational comprehensive approach
Risk Sensitive Land Use Planning

5. Risk Sensitive Land Use Planning
Step 1: Hazard Identification and Analysis
Analysis of:
Hazards that may occur in a given area
The history of the hazard occurrence
The hazard intensity and impact
Change in exposure with respect to time
Areas that would be most affected within the city
Population groups impacted the most
Quantifies severity of hazard at a given site
As a point estimate, or
As a time-dependent probabilistic statement
Results can be mapped to increase understanding and usage
Geographic Information Systems can be useful
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6. Risk Sensitive Land Use Planning
Step 2: Vulnerability Analysis
Quantifies the degree of susceptibility of people and assets to sustain damage under various levels of hazard
Physical vulnerability varies across a city and depends on the existing building stock and site conditions
Socio-economic vulnerability depends on population distribution, socio-economic status, gender, race/ethnicity, age, nature of economy etc.
Indicates elements at risk that need land use planning interventions
Integrates capacity analysis to estimate protective and coping capabilities
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7. Risk Sensitive Land Use Planning
Step 3: Risk Analysis
Combines parameters of hazard and vulnerability to quantify losses
Losses may include casualty, direct material losses and indirect material losses
May or may not be time-dependent
Time dependent risk assessment provides basis to determine acceptable level of risk
Can be used to determine benefit-cost for land use planning interventions
Level of precision/approximation of risk assessment depends on purpose of its use
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8. Risk Sensitive Land Use Planning
Risk Assessment: Methods & Approaches
Risk Assessment
Quantitative
Qualitative
Expert-driven
Community-driven
Use analytical tools
Provides technical and financial parameters for land use planning
Suitable for subjective data that is difficult to quantify
Do not require high level of technical expertise
Can be performed by various stakeholders
Performed by experts
Requires high level of technical expertise
Relies on quantitative methods
Participatory in nature
Incorporate variations in perception and acceptability of risk of stakeholders
Community-based hazard and risk mapping
Vulnerability and capacity assessments
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9. Risk Sensitive Land Use Planning
Risk Assessment Techniques: Risk Identification
Determines hazards that may occur in area
Includes description of area and its environment
Identifies and characterizes susceptible elements to the hazard
Includes vulnerability and capacity of population, institutions and critical facilities
Uses mapping tools to facilitate the process of stakeholders’ consultation and provide input to land use planning
Risk Sensitive Land Use Planning

10. Risk Sensitive Land Use Planning
Risk Assessment Techniques: Risk Checklist
Best for a specific project, event or area
Best for parameters that are difficult to quantify
Helps planners follow systematic procedure for land use decisions
Risk Sensitive Land Use Planning

11. Risk Sensitive Land Use Planning
Risk Assessment Techniques: Risk Matrix
Charts parameters of frequency versus severity of hazards
Uses two-dimensional chart
Can be both quantitative and qualitative
Interpretation must be consistent
Used by planners to prioritize types of risks
Risk Sensitive Land Use Planning

12. Risk Assessment Techniques: Risk Matrix
Ranking of multiple locations on basis of a risk index (Location 2 has highest risk)
Location 1
Location 2
Location 3
Location 4
Severity of Hazard 3 5 4 2
Frequency of Hazard 1
Human Loss Potential
Economic Loss Potential
Response Capacity
Cumulative 17 21 18 13
Risk Index to Community
Risk Sensitive Land Use Planning

13. Risk Sensitive Land Use Planning
Risk Assessment Techniques: Risk Matrix
Ranking of multiple hazards
Very High
High
Medium
Low
Very Low
Forest Fires
Floods
Droughts
Epidemics
Technological
Earthquakes
FREQUENCY
SEVERITY (LOSS)
Risk Sensitive Land Use Planning

14. Risk Sensitive Land Use Planning
Risk Assessment Methods: Scenario Analysis
Calculates potential losses from a hypothetical event
Provides understanding of the spatial distribution of losses to the built environment
Develops internal institutional knowledge regarding vulnerabilities of infrastructure and population
Serves as effective communication tool between various stakeholders
Steps involve:
Creating an inventory of built environment, human exposure, and economic value
Analysis of potential hazards
Analysis of potential damage
Translation into social and economic loss
Risk Sensitive Land Use Planning

15. Risk Sensitive Land Use Planning
Risk Assessment Methods: Time – based Probabilistic Assessment
Estimates disaster loss from multiple events and the probability of occurrence of each event in time
Analytically most sophisticated
Important for planners to understand the concepts of probabilistic assessment
Forms basis for: building code regulation, micro-zoning, benefit/cost analysis of risk reduction options
Used to establish a threshold for acceptable risk
Provides spatial distribution of severity of various hazards at a high level of resolution
Risk Sensitive Land Use Planning

16. Using the Results: Establishment of Basic Planning Parameters
Based on participatory approach to:
Establish level of acceptable risk
Establish priorities
Set planning strategies and interventions
Look at options to reduce risk:
Transfer or share
Eliminate or avoid
Accept, or retain and manage
Mitigate
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17. Risk Sensitive Land Use Planning
Monitoring Implementation
Continuously monitor status of risk and interaction with land use
Factor into risk assessment and land use planning process the changes in risk
Check the effectiveness of land use planning measures in reducing risk by:
Using monitoring and evaluation forms
Scheduling regular monitoring activities
Assigning responsible parties
Submitting progress reports
Using indicators and benchmarks
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18. Risk Sensitive Land Use Planning
Challenges to Risk Assessment
Multiple hazards to which people are simultaneously exposed
Difficulty in aggregating vulnerability across sectors
Wide range of assets to be accounted for in measuring vulnerability and capacity
Large number of stakeholders with roles to play in shaping risk
Unequal access to technology, Inequality in the distribution of human resources, as well as hardware and inability to buy in data from private sources
Focus on built assets at risk and less on people
Difficulty of measuring human vulnerability
Rapid changes in slums and low-income settlements
Inability to include highly vulnerable populations in assessments
Difference in expert risk assessments and public perceptions of risk
Risk Sensitive Land Use Planning