2022 – The Bureau of Reclamation approach to risk analysis and risk informed decision making – past successes, current challenges, and future direction

D. Galic – U.S. Department of the Interior, Bureau of Reclamation, Denver, CO, USA
J.L. Major – U.S. Department of the Interior, Bureau of Reclamation (retired)

Reclamation’s inventory of high hazard dams includes over 360 individual structures spread over roughly 240 facilities. To effectively administer and maintain an inventory of this size, it is important to have a reliable tool for evaluating the significance of unusual performance observations, as well as a systematic means of prioritizing dam safety spending. Reclamation uses the risk informed decision making (RIDM) process to address both of these needs. The paper gives an overview of RIDM from the perspective of two experienced practitioners, including the mathematical and philosophical basis for the process and a discussion of each of its individual steps (risk analysis, risk assessment, and risk management). Examples of how the RIDM process has been successfully applied in the past are discussed, along with some of the challenges encountered over several decades of risk analysis practice. The paper also examines the role of the RIDM process in the post – Oroville regulatory and dam safety environment, and concludes with a preview of upcoming changes to Reclamation’s public protection guidelines (PPG), including those associated with the evaluation of non-breach incident threats at Reclamation dams.