FLOOD RISK ASSESSMENT

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FLOOD RISK ASSESSMENT

• Training Course on
• Factoring Hydro-Climatic Disasters in IWRM

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Goal

• Explain the occurrence, impact and assessment of
  floods as a natural phenomenon.
• Outlines the risk reduction measures and
  practices that can be used to build the
  resilience of the local communities for coping
  with Floods at the catchment level.
•  
• Learning Objectives 
• To understand types, factors and indicators of
  floods
• To understand severity and risks associated with
  floods
• To establish a basis for flood management as a
  type of natural disaster

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Introduction

• Flood is a general and temporary condition of
  partial or complete inundation of normally dry
  land areas from
• the overflow of inland waters, and
• the unusual and rapid accumulation of runoff of
  surface waters from any source.

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Flood Management

• Flood management is a broad concept that focuses
  on reducing flood hazards through a combination
  of policy, institutional, regulatory and physical
  measures, while recognizing that floods can never
  be fully controlled
• This takes into account the beneficial uses of
  floods, which are difficult to quantify in human
  and economic terms but which sustain natural
  systems that also have economic, social, cultural
  and ecosystem values and functions.

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Flood Risk Management

• A change to proactive management of natural
  disasters requires an identification of the risk,
  the development of strategies to reduce that
  risk, and the creation of policies and programmes
  to put these strategies into effect
• Risk management is a fundamental activity geared
  to the evaluation of schemes for reducing but not
  necessarily eliminating the overall risk, as in
  many cases risk cannot be entirely eliminated

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Flood Risk Management

• Steps associated with risk assessment and
  management includes
• Assessing the potential for a hazard to occur
• Vulnerability analysis to provide an
  understanding of the consequences should an event
  of a certain magnitude and frequency occur.
• Based on this initial work, various mitigation
  measures evaluated to assess their ability for
  reducing risk exposure
• Disaster management plans and specific mitigation
  measures can be identified
• Efforts then be undertaken to implement the
  selected mitigation measures

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Flood risk and Vulnerability Assessment

• A basin flood management plan has to start with
  assessing the present and future flood risks.
  Flood risks are function of
• magnitude of the hazard,
• degree of exposure to the hazard and
• vulnerability of society against damage due to
  the hazard.

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Understanding flood hazard and flooding

• This may require
• hydro meteorological analysis
• hydrologic and hydraulic simulation of surface
  runoffs, floods and inundations
• mechanism of flooding
• simulation and analysis projected conditions of
  land use change, future developments (e.g.,
  urbanization, infrastructure development etc
• future trends of hydro-meteorological phenomenon
  due to climate variability or change.

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Integrated Flood Management- A new approach

• Integrated Flood Management (IFM) is a process
  that promotes an integrated, rather than
  fragmented, approach to flood management.
• It integrates land and water resources
  development in a river basin, within the context
  of integrated water resources management (IWRM),
  and aims to maximize the net benefit from
  floodplains and to minimize loss to life from
  flooding.

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Integration

• Integrated flood management recognizes
• Interconnection of flood management
• actions within broader water resources
• management
• Value of coordinating across geographic and
  agency boundaries
• Need to evaluate opportunities and potential
  impacts from a system perspective
• Importance of environmental stewardship and
  sustainability

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IFM PERSPECTIVE
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Supportive Technologies

• A number of tools are available to array and
  display information for
• the use of technical experts,
• to explain programmes of flood damage reduction
  to the decision-makers, and
• to communicate real time forecasts and warnings
  to the public.
• These include
• Geographic Information Systems (GIS)
• Mapping
• Visualization techniques

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Approaches to Flood Control
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Thank you for your attention