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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.
 
Chapter Title Latest Update
*
Complete Best Practices Document
All Presenations
2011
0
Cover, Introduction, and Table of Contents
Presentation
April 2011
1
Potential Failure Mode Identification, Description, and Screening
Presentation
April 6, 2010
2
Seismic Hazard Analysis
Presentation
April 4, 2011
3
Hydrologic Hazard Analysis
Presentation
April 13, 2010
4
Reservoir Level Exceedance Curves
Presentation
June 19, 2009
5
Consequences of Dam Failure
Presentation
August 2010
6
Event Trees
Presentation
Load Uncertainty Presentation
March 14, 2011
7
Probabilistic Stability Analysis (Reliability Analysis)
Presentation
July 2, 2010
8
Subjective Probability and Expert Elicitation
Presentation
June 20, 2009
9
Erosion of Rock and Soil
Presentation
March 29, 2011
10
Reinforced Concrete Fragility
Presentation
March 11, 2011
11
Flood Overtopping Failure of Dams
Presentation
June 18, 2009
12
Risk Analysis for Concrete Gravity Dams
Presentation
July 2, 2009
13
Risk Analysis for Concrete Arch Dams
Presentation
April 6, 2010
14
Risk Analysis for Concrete Buttress Dams
Presentation
June 9, 2009
15
Seismic Failure of Spillway Radial Gates
Presentation
June 20, 2009
16
Trunnion Friction Radial Gate Failure
Presentation
March 19, 2011
17
Seismic Spillway Pier Failure
Presentation
March 19, 2011
18
Drum Gates and Other Gates
Presentation
March 14, 2011
18 B
Mechanical Electrical Systems
Presentation
May 2010
19
Stagnation Pressure Failure of Spillway Chutes
Presentation
June 17, 2009
20
Cavitation Damage Induced Failure of Spillways
Presentation
June 17, 2009
21
Overtopping of Walls and Stilling Basin Failure
Presentation
April 10, 2010
22
Seismic Risks for Embankments
Presentation
July 2, 2010
23
Seismic Failure of Spillway/Retaining Walls
Presentation
March 19, 2011
24
Internal Erosion and Piping Risks for Embankments
Presentation
April 7, 2010
25
Landslide Risks
Presentation
July 2, 2010
26
Risk Estimates for Operational Failure
Presentation
April 7, 2010
27
Construction Risk
Presentation
July 2010
28
Combining and Portraying Risks
Presentation
March 26, 2011
29
Building the Case
Presentation
July 2009
30
Public Risk Tolerance and Risk Guidelines
Presentation
May 3, 2010
31
Qualitative and Semi-Quantitative Risk Assessment
Presentation
April 7, 2010
32
Facilitating Risk Analysis
Presentation
February 7, 2009
33
Glossary
December 3, 2009
34
Exercise Solutions
Smoky Ridge
May 6, 2010

 


Last Updated: 11/03/2011
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