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1 Chapter 8 Risk Management and Disaster Preparedness
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2 Introduction Life-cycle management of infrastructure requires that water, sewer, and storm water utilities provide safe and reliable service in spite of earthquakes, floods, accidents, and even terrorist attacks. This requires infrastructure managers to deal with several forms of risk that go well beyond engineering design. They do this by adding security and risk management to other tasks of planning, design, construction operation, and maintenance. Providing security and avoiding disasters should become part of everyday business in utilities.
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3 The world of risk has expanded, and the purposes of this chapter are: To outline the risks Relate them to the integrity of infrastructure systems Explain how to reduce vulnerability (weakness). One tool for reducing vulnerability is the “vulnerability assessment”. Introduction
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4 Consequences of disasters and emergencies can be dire ( وخيمة ). Some listed by the AWWA for water utilities are the following: Personnel shortages Contamination of water supplies Contamination of air Well and pump damage Pipeline breaks and appurtenance damage Structure damage Equipment and material damage or loss Introduction
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5 Consequences of disasters and emergencies can be dire. Some listed by the AWWA for water utilities are the following: Process tank or basin damage Electric power outage Communications disruption (disturbance) Transportation failure Hazardous effects on system components Introduction
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6 Risks to water, sewer, and storm water systems Reducing vulnerability and improving reliability are two sides of the same coin. Threats will always be there, but if vulnerability can be reduced, utility services can continue in spite of them. Reducing vulnerability and improving reliability extend to almost everything that the utility does, and are quality management issues. The most visible risks to water, sewer, and storm water systems involve public health and safety, which affect system design and management and require capital investments and decisions
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7 Risk categoryWater supplyWastewaterStorm water Health, safety, environment Contamination, sickness, death Contamination, damage to property, health risks, environmental damage Children playing around flood facilities, pipes, ponds, etc. Performance failureLoss of fire flow Overflow of untreated sewage and enforcement action Inadequate protection from flooding Construction or maintenance failure Another utility damages pipe during digging Trench cave-in Pipe damaged during construction System or component failure Pipe break Sewer backup due to clogging, leading to property damage Flooding due to clogged facilities, leading to property damage Liability Pipe leak leads to cave-in and damage to property Industrial waste contaminates aquifer Redirected flood waters damage property Financial Rates are inadequate to pay costs for utility, leading to crisis Inadequate rates to pay for improvements, leading to fine Utility held responsible for damage, not able to pay judgment Employee problems and accidents Employee inhales chlorine Employee injured in maintenance event Employee sues for discrimination Disaster, human- caused Pranksters contaminate water in tank Construction project damages large sewer Industry dumps toxic waste in drainage system Disaster, naturalBreaks due to earthquakesTornado damages treatment plantFlood overwhelms facilities Table 8.1 : Risks to Water, Sewer, and Storm water Systems Risks to water, sewer, and storm water systems
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9 SF Bay Quake 3 Risks to water, sewer, and storm water systems
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10 GF WTP Risks to water, sewer, and storm water systems
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11 Elba pumping Risks to water, sewer, and storm water systems
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12 Risk management Risk management is the term used to explain the different ways an organization handles risk. In risk management: 1.One considers hazards that can threaten vulnerable elements of a system 2.Assesses risks and results. 3.Develops actions, including mitigation, response, recovery, and communication to essential groups.
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13 Risk management
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14 Many different terms are used in the risk management field. They include hazard assessment, disaster mitigation, risk assessment and reduction, vulnerability assessment, mitigation, emergency management, and contingency planning, among others. On close inspection, however, these fields involve the same general processes, which are identifying, managing, and responding to threats to an organization, and seeking to answer the following questions: Risk management
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15 What can go wrong and why (what are the hazards and threats, what disaster can occur)? How likely is it (what is the risk, chance, probability)? How bad can it be (who or what would be affected, what is the vulnerability, what would be the consequences (cost or penalty)? What can we do about it (what should be the management actions, mitigation, response, or recovery)? Risk management
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16 These can be reduced to a few essential steps. Determine, recognize, and appreciate all potential out- of-course events (hazard assessment). Determine (measure) levels of these risks (risk assessment). Reduce levels of risk to as low as reasonably practicable or to acceptable levels (risk reduction). Determine how and why each out-of-course event can affect people, places, and processes and the consequences of the effects (vulnerability assessment). Establish means and mechanisms by which consequences can be counterbalanced in a manner acceptable to business and regulators (mitigation). Risk management
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17 Risk management
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18 For storm water systems, the purpose of the system is to handle hazards, but we do not normally considered interrupting (stopping) regular service as hazard, as we do in water supply and wastewater. Storm water systems are designed based on acceptable risks. But storm water systems do present risks, in similar ways to water supply and wastewater. For example, close links between stormwater and transportation facilities increased interdependence between the systems and can increase risk. Risk management
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19 Risk assessment, vulnerability analysis, and contingency planning Risk assessment or analysis is the systematic use of information to identify sources and to estimate the risk. Achieving this is the goal of contingency planning, in which levels of risks must be measured and be reduced to as low as reasonably practicable.
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20 Risk assessment, vulnerability analysis, and contingency planning
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21 The science of measuring risks is well advanced for some threats but not for others. In general, risks to water, sewer, and storm water systems would be difficult to quantify, although possibilities can be listed and mapped, as shown before. Risk assessment, vulnerability analysis, and contingency planning
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22 The general process of contingency planning involves: 1.Perform disaster scenarios 2.Estimating demand 3.Identifying measures for meeting minimum needs 4.Isolating critical components or systems that may cause system failures. This is generally referred to as vulnerability assessment or analysis. Risk assessment, vulnerability analysis, and contingency planning
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23 Vulnerability analysis means to determine the consequences of the hazards affecting the facility or operations of concern. It requires: 1.Identification and measurement of risk 2.Identifies vulnerabilities. Risk assessment, vulnerability analysis, and contingency planning
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24 Vulnerability analysis presents: 1.Historical data about past disasters 2.Assesses future probability and frequency of emergencies and disasters 3.Analyzes impacts and effects 4.Validates data. Risk assessment, vulnerability analysis, and contingency planning
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25 In vulnerability analysis, the effects of the hazards on water system components and water quality and quantity should be determined. The entire system should of course be analyzed, as well as the components. 1.Identify components of the water supply system. 2.Estimate potential effects of possible disasters. 3.Create goals for performance and levels of service. 4.Identify critical components. Risk assessment, vulnerability analysis, and contingency planning
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26 These steps, although stated for water supply systems, apply to sewer and storm water as well. They would be implemented this way: 1.Identification of system components requires: An inventory with maps Condition inspections Data for operations and maintenance scenarios, including emergency actions. Risk assessment, vulnerability analysis, and contingency planning
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27 2. Quantifying magnitude determines the scale and magnitude of each potential disaster or contingency. Estimating effects of expected disasters on each component of the system involves disaggregation of systems to assess the effects of each disaster type on each component (for example, a storage reservoir might be vulnerable to a mudslide, whereas the treatment plant might fail during a power outage). Risk assessment, vulnerability analysis, and contingency planning
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28 3. Estimating demand during and after the disaster for all purposes Determining the capability of a system to meet demands during emergencies requires modeling and analysis to match demands and supplies during the emergency. Risk assessment, vulnerability analysis, and contingency planning
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29 4. Identifying critical components that cause failure during emergencies is the result of the vulnerability analysis and pinpoints the components that need strengthening. Risk assessment, vulnerability analysis, and contingency planning
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30 Risk assessment, vulnerability analysis, and contingency planning
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31 Mitigation measures, including design and construction Mitigation consists of “disaster-proofing” activities which eliminate or reduce the probability of disaster effects
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32 Reliability as a key design goal means the extent to which a system performs its function without failure. A systems approach would make sure failure of a component does not lead to failure of system. Reliability depends on treatment train, equipment, processes, standby equipment, redundancy, parallel systems, and flexibility. Mitigation measures, including design and construction
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33 Principles and ideas for reliable systems are: Ensure that failure of any one component does not cause operating failure or noncompliance. Provide operational flexibility to handle problems with source water variability. Have reserves and redundancies to keep operating if one unit is out of service. Have one or more processes perform the same function, such as filters and sedimentation to remove particulates. Gain flexibility through redundancy, conservative sizing, or unit arrangements. Mitigation measures, including design and construction
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34 Principles and ideas for reliable systems are: Ensure overall reliability through interconnections and different sources. Avoid independent process trains; use interconnections instead. Use gravity flow instead of pumping. Ensure component system reliability — electrical, controls, and many other factors. Consider disasters in design. Use waterproofing. Control access. Have plant security. Mitigation measures, including design and construction
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35 Principles and ideas for reliable systems are: Store chemicals on site to mitigate truck blockades. Have on-site generation of chemicals, chlorine. Have a HAZMAT program. Have a safety program. Do a vulnerability analysis. Have multiple intake ports or well screens. Use off-stream sources. Mitigation measures, including design and construction
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36 Principles and ideas for reliable systems are: Have dual power sources and standby power. Have chemical storage reliability. Ensure reliability of process design. Ensure smooth O&M. Have shop drawings. Have computerized maintenance systems. Have trained people. Mitigation measures, including design and construction
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