13.1.3 Examples of Monetary Acceptable and/or
Tolerance Thresholds Curves . . . . . . . . . . . . . . . . . 191
13.2 Modern Risk Tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
13.2.1 Corporate Risk Tolerance (CRT) . . . . . . . . . . . . . . . 192
13.2.2 Societal Risk Tolerance . . . . . . . . . . . . . . . . . . . . . 193
13.2.3 Tolerance Versus Time and Tolerance Zones . . . . . . 194
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
14 Risk Assessment for the Twenty-First Century . . . . . . . . . . . . . . . . 199
14.1 ISO 31000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
14.2 Manageable-Unmanageable and Strategic Risk Definition . . . . 202
14.3 What to Do with Those Risks Families? . . . . . . . . . . . . . . . . 204
14.4 Using the ORE Concept for Dams Systems . . . . . . . . . . . . . . 205
14.5 Synergistic Methodologies . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
14.5.1 An Example of Results Display . . . . . . . . . . . . . . . . 209
14.5.2 Using Risk Dashboards . . . . . . . . . . . . . . . . . . . . . . 210
14.6 How, Who, How Often? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
14.6.1 How to Perform a Residual Risk Assessment? . . . . . 212
14.6.2 Who Has to Perform Residual Risk Assessment? . . . 212
14.6.3 How Often Should a Residual Risk Assessment
Be Performed? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
14.7 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Part III Case Histories and a Look into the Future
15 Risk-Informed Decision Making . . . . . . . . . . . . . . . . . . . . . . . . . . . 219
15.1 Portfolio Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
15.1.1 General Descriptions of the Dams . . . . . . . . . . . . . . 220
15.1.2 Interdependencies of the Dams . . . . . . . . . . . . . . . . 223
15.1.3 Ancillary Structures and Other Dam Conditions . . . . 223
15.1.4 Scheme of the System . . . . . . . . . . . . . . . . . . . . . . 223
15.1.5 Geotechnical Conditions as Reported by
Engineering Reports . . . . . . . . . . . . . . . . . . . . . . . . 223
15.2 Engineering Stability Analyses of the Dams . . . . . . . . . . . . . . 225
15.3 Conditions from Inception to the Date of Analysis
of the Dams (Physical and Governance) . . . . . . . . . . . . . . . . . 226
15.3.1 Dam 1A and Dam 1B . . . . . . . . . . . . . . . . . . . . . . . 226
15.3.2 Dam 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
15.3.3 Dam 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
15.3.4 Dam 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230
15.4 Success and Failure Criteria . . . . . . . . . . . . . . . . . . . . . . . . . 230
15.5 Probability of Failure of the Portfolio’s Dams . . . . . . . . . . . . 231
15.5.1 Dam 1A, 1B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
15.5.2 Dam 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
Contents
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