6.4 Oroville IFT Lesson Learned
71
mainly due to insufficient expertise regarding spillway failure modes and mischaracterization
of the geology. Confirmation bias related to perpetuating misunderstanding of the geologic
conditions at the spillways likely contributed to this ignorance of risks. There was also a
degree of complacency regarding tolerating risks, and some overconfidence in ability to
manage risks.
Appendix J concludes by stating:
Overall, in terms of human factors, the safety “demands” which contributed to failure were
significant, while the systemic “capacity” to meet those demands and maintain dam safety
was substantially lacking in many areas. Half a century after design and construction of
the spillways, this systemic imbalance in human factors had set the stage physically for the
spillway incident to occur in February 2017.
The application of the human factors framework by the IFT has illustrated the need
for its use not only in dam failure reviews but also for periodic integrity reviews and in
support of a wide range of decisions, judgments, management system requirements
and risk assessments. How advanced risk assessment methodology can provide the
discipline and rigor to identify and address the human barriers to safety will be a
major focus of this book.
6.4.2 ITF Lessons on Risk Identification and Management
The lessons summarized above regarding failure mode analysis, comprehensive
facility reviews and physical inspections all emphasize the importance of risk identification and management. The identified weaknesses of the Potential Failure Mode
Analysis (PFMA) approach are real and specific suggestions for improvement to
the PFMA process were presented in Appendix F3 of the ITF report. Many valid
suggestions were made, but it is not sufficient just to do a better job of PFMA’s. A
more rigorous and disciplined approach is needed. With regard to the suggestion that
more comprehensive reviews are required, the added depth and detail that would be
provided will establish a solid base for the effectiveness of whatever risk assessment
methodology that may be applied.
With respect to physical inspections, regulatory compliance and owner’s dam
safety programs, a risk-based approach to support and guide these activities would
definitely add value in terms of developing and effective surveillance and monitoring
program and providing the basis for corporate and government oversight of the critical
issues.
6.4.3 What Else Can the IFT Report Tell Us?
The IFT Report offers wealth of insights, observations, findings and lessons. If they
could be compressed into one page, the key points might be as follows:
71
mainly due to insufficient expertise regarding spillway failure modes and mischaracterization
of the geology. Confirmation bias related to perpetuating misunderstanding of the geologic
conditions at the spillways likely contributed to this ignorance of risks. There was also a
degree of complacency regarding tolerating risks, and some overconfidence in ability to
manage risks.
Appendix J concludes by stating:
Overall, in terms of human factors, the safety “demands” which contributed to failure were
significant, while the systemic “capacity” to meet those demands and maintain dam safety
was substantially lacking in many areas. Half a century after design and construction of
the spillways, this systemic imbalance in human factors had set the stage physically for the
spillway incident to occur in February 2017.
The application of the human factors framework by the IFT has illustrated the need
for its use not only in dam failure reviews but also for periodic integrity reviews and in
support of a wide range of decisions, judgments, management system requirements
and risk assessments. How advanced risk assessment methodology can provide the
discipline and rigor to identify and address the human barriers to safety will be a
major focus of this book.
6.4.2 ITF Lessons on Risk Identification and Management
The lessons summarized above regarding failure mode analysis, comprehensive
facility reviews and physical inspections all emphasize the importance of risk identification and management. The identified weaknesses of the Potential Failure Mode
Analysis (PFMA) approach are real and specific suggestions for improvement to
the PFMA process were presented in Appendix F3 of the ITF report. Many valid
suggestions were made, but it is not sufficient just to do a better job of PFMA’s. A
more rigorous and disciplined approach is needed. With regard to the suggestion that
more comprehensive reviews are required, the added depth and detail that would be
provided will establish a solid base for the effectiveness of whatever risk assessment
methodology that may be applied.
With respect to physical inspections, regulatory compliance and owner’s dam
safety programs, a risk-based approach to support and guide these activities would
definitely add value in terms of developing and effective surveillance and monitoring
program and providing the basis for corporate and government oversight of the critical
issues.
6.4.3 What Else Can the IFT Report Tell Us?
The IFT Report offers wealth of insights, observations, findings and lessons. If they
could be compressed into one page, the key points might be as follows: