Loss of Life Consequence Assessment for Dam Failure Scenarios: On-Demand

This webinar looks at the evaluation of loss of life resulting from a dam failure, use of loss of life estimates, hazard classification, improvement of emergency action planning, determination of individual and societal risk, a comparison of loss of life from dam failure to loss of life from natural hazards, the history of dam failure loss of life estimation with a focus on Bureau of Reclamation involvement, and learning from the past – factors that influenced loss of life during significant U.S. dam failures.

Wayne J. Graham, P.E.

Civil Engineer

Mr. Graham received a M.S. degree in Civil Engineering from Colorado State University, Fort Collins, Colorado.  He worked for the Bureau of Reclamation from 1979 through June 2011.  While at Reclamation, he was responsible for preparing dam failure inundation mapping guidelines, inundation maps, and downstream hazard potential classifications. He is currently working part-time for Reclamation as a rehired annuitant.

Lawn Lake Dam, located north of Denver, Colorado failed in 1982 and piqued an interest in dam failure consequences.  Why do the failures of some dams cause large loss of life while others cause little or no loss of life?  In every event, some things are out of our control, such as the flood severity and when the event occurs, while some things are within our control, such as whether dam failure warnings are issued.  He began researching the factors that influence the loss of life resulting from dam failure.

He has been to the site of several dam accidents or failures including:  Vajont Dam, Italy; Bradford Dam, England; South Fork Dam, Johnstown, Pennsylvania; St. Francis Dam, California; Walnut Grove Dam, Arizona; Mill River Dam, Massachusetts; Buffalo Creek, West Virginia; Kelly Barnes, Georgia; Teton Dam, Idaho; and many others.

In 1999, Mr. Graham authored DSO-99-06, “A Procedure for Estimating Loss of Life Caused by Dam Failure.”  The procedure is useful, robust, easy to apply, and produces plausible results.  This procedure has provided a useful tool as Reclamation uses risk analysis, which evaluates the probability of adverse consequences, as the primary support for dam safety decision-making.

Mr. Graham has made presentations at several ASDSO Annual Conferences.  Two articles that he published in ASDSO’s Journal of Dam Safety would be good background reading. The first article discusses the difficulty in achieving a success evacuation and the second describes a sequence of dam failures that resulted in the largest loss of life every from any dam failure.

“Get Out – Get Out – Get Out!  Getting People Out of Harm’s Way,” Volume 7, Issue 1, 2009.

“The Banqiao and Shimantan Dam Failures: Factors Affecting the Warning and Evacuation Success,” Volume 8, Issue 4, 2010.


On- Demand Viewing
Open to view video.
Open to view video.
Post Survey
4 Questions
4 Questions Post Survey
Completion Quiz
10 Questions  |  3 attempts  |  6/10 points to pass
10 Questions  |  3 attempts  |  6/10 points to pass Completion Quiz
Completion Certificate
2.00 PDH credits  |  Certificate available
2.00 PDH credits  |  Certificate available Completion Certificate