Risk Management

Best Practices and Risk Methodology

The Bureau of Reclamation has been using risk analysis as the primary support for dam safety decision-making for about 15 years, and has developed procedures to analyze risks for a multitude of potential failure modes. Manuals, guidelines, standards, and practical reference material on how to perform risk analysis for dam safety applications are lacking. The Best Practices Training Manual contains what are considered the "Best Practices" currently in use for estimating dam safety risks at the Bureau of Reclamation. Risk analysis at the Bureau of Reclamation has evolved over the years and will continue to evolve. Therefore, updates to this manual are planned in the future as significant improvements are developed.

From the outset of implementing risk analysis, Reclamation recognized that procedures and data available for dam safety risk analysis, while quantitative, do not provide precise numerical results. Therefore, this manual strives to present useful information, tools, and techniques, while stopping short of a "cookbook" approach. This allows the risk analyst(s) to use the proper balance of engineering judgment and calculations in estimating risks, and to understand and "build the case" for what is influencing the risks the most. Thus, the numbers, while important, are less important than understanding and documenting what the major risk contributors are and why.

The Bureau of Reclamation conducts risk analysis at different levels, from screening level analyses performed by an individual (with peer review) during a Comprehensive Facility Review (CFR), to full blown facilitated team risk analyses, which include participation by field personnel. It is envisioned that the tools presented in this manual can be used for any level of risk analysis. The primary difference will be the level of detail to which the analyses are carried. These differences are noted where appropriate.

Contact for course information: Bill Fiedler (WFiedler@usbr.gov)

Best Practices Chapters

Please note that these documents are intended to serve as instruction material during the training course of the same name and should not be used as a stand-alone reference. In many cases, additional details should be sought from the available references or an experienced risk analyst. 
Reclamation - Presentation
USACE - Presentation
 
Chapter Title Latest Update
I-0

Cover and Table of Contents 
Presentation

June 12, 2015
I-1
Basics of Probability and Statistics
Presentation 
May 7, 2015
I-2
Geologic and Geotechnical Information Required for Risk Assessment
Presentation 
April 1, 2015
I-3
Potential Failure Mode Analysis
Presentation 
March 13, 2015
I-4
Semi-Quantitative Risk Analysis
April 13, 2015
I-5
Event Trees
Presentation
May 7, 2015
I-6
Subjective Probability and Expert Elicitation
Presentation 
May 21, 2015
I-7
Probabilistic Stability Analysis (Reliability Analysis)
Presentation 
March 17, 2015
I-8
Combining and Portraying Risks
Presentation
May 7, 2015
I-9
Building the Case
Presentation
May 27, 2015
I-10
Facilitator Considerations
Presentation
March 10, 2015
II-1
Reservoir and River Stage Exceedance Probabilities
Presentation
May 11, 2015
II-2
Probabilistic Hydrologic Hazard Analysis
Presentation
June 12, 2015
II-3
Seismic Hazard Analysis
Presentation
June 20, 2015
III-1
Consequences of Flooding
Introduction Presentation
November 28, 2014
IV-1
Erosion of Rock and Soil
Presentation
June 18, 2015
IV-2
Flood Overtopping Failure of Dams and Levees
Presentation
November 26, 2012
IV-3
Embankment Slope Instability
June 9, 2015
IV-4
Invernal Erosion Risks for Embankments and Foundations
Table 1
Table 2
Table 3
Table 4
Table 5
Table 6
Table 7
Table 8
Table 9
Presentation
June 17, 2015
IV-5
Foundation Risks for Concrete Dams
Presentation
May 11, 2015
IV-6
Seismic Risks for Embankments
Presentation
April 2, 2015
V-1
Reinforced Concrete Failure Mechanisms
Presentation
April 22, 2015
V-2
Risk Analysis for Concrete Gravity Structures
Presentation
June 11, 2015
V-3
Risk Analysis for Concrete Arch Dams
Presentation
June 12, 2015
V-4
Risk Analysis for Concrete Buttress Dams
Presentation
June 9, 2009
V-5
Levee Floodwalls
Presentation
November 7, 2012
V-6
Seismic Spillway Pier Failure
Presentation
April 22, 2015
V-7
Seismic Retaining Wall Failure
April 22, 2015
VI-1
Stagnation Pressure Failure of Spillway Chutes
Presentation
June 10, 2015
VI-2
Overtopping of Walls and Stilling Basin Failure
June 10, 2015
VI-3
Cavitation Damage Induced Failure of Spillways
June 10, 2015
VII-1
Failure of Radial (Tainter) Gates under Normal Operational Condition
Presentation
May 27, 2015
VII-3
Seismic Failure of Spillway Radial (Tainter) Gates
June 8, 2015
VII-4
Probability of Failure of Mechanical or Electrical Systems on Dam Gates
Presentation
October 9, 2012
VIII-1
Operational Risks
Presentation
March 19, 2015
VIII-2
Landslide Risks
Presentation
June 15, 2015
VIII-3
Construction Risks
Presentation
October 31, 2012
VIII-4
Hydrologic Systems Risk - Presentation
February 26, 2015
IX-1
Risk Assessment/Management
Presentation
May 11, 2015
X-1
Possible Exercise Solutions
June 18, 2015 
X-2
Smoky Ridge Wrap-Up - Presentation
February 27, 2015

 

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Last Updated: 7/30/15