Loss of Life Consequence Assessment for Dam Failure Scenarios

This webinar is designed to provide dam owners, emergency managers, and other relevant stakeholders with information needed to define and estimate loss of life consequences for dam failure scenarios. The course will provide participants with an overview and description of current consequence estimation methodologies, including information on the technical capability and resource requirements for each. The course will highlight the importance of defining dam failure scenarios and assessing consequences through the presentation of case studies. The course will provide participants with an understanding of the complexity associated with providing a warning that results in people taking protective action.

Specific instructions and detailed examples for computing loss of life consequences will be provided for some of the more commonly used procedures and methodologies. Participants will be provided with the concepts of how consequence assessment is an important part of risk management strategies and how consequence estimation can be used to make improvements in emergency preparedness efforts.

Speaker and Presenter Information

Wayne J. Graham, P.E

I received a M.S. degree in Civil Engineering from Colorado State University, Fort Collins, Colorado. I worked for the Bureau of Reclamation from 1979 through June 2011. While at Reclamation, I was responsible for preparing dam failure inundation mapping guidelines, inundation maps, and downstream hazard potential classifications. I am 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. I began researching the factors that influence the loss of life resulting from dam failure.

I have 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, WestVirginia; Kelly Barnes, Georgia; Teton Dam, Idaho; and many others.

In 1999, I 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.

I have made presentations at several ASDSO Annual Conferences. Two articles that I have had published in ASDSO’s Journal of Dam Safety would be good background reading before the webinar takes place. 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.

Relevant Government Agencies

Army, Dept of Energy, Dept of Homeland Security, Dept of the Interior, Other Federal Agencies, State Government, County Government, City Government, Municipal Government, FEMA, Federal Government, State & Local Government