Federal Guidelines for Dam Safety Risk Management (FEMA P-1025)
Federal Emergency Management Agency, 2015
The term risk, when used in the context of dam safety, is comprised of three parts: (1) the likelihood of occurrence of aload (e.g., flood, earthquake, etc.), (2)the likelihood of an adverse structural response(e.g.,dam failure, damaging spillway discharge, etc.), and (3) the magnitude of the consequences resulting from that adverse event (e.g., life loss, economic damages, environmental damages, etc.). Typically, the direct consequences of dam failure are estimated. Indirect consequences could also result, in which failure of the dam results in loss or failure of key facilities, which can ultimately lead to additional economic consequences or loss of life. If indirect consequences can be identified and estimated, they can be incorporated into the risk estimates. In some cases, it may not be possible to capture all of the indirect consequences. Figure 2 depicts the flow of recurring dam safety activities and how risk information is used to inform decisions on dam safety actions and setting priorities.
Risk estimates typically reflect the risk at a given dam at the snapshot in time when the risk analysis is performed. It is recognized that the conditions at the dam will likely change in the future and the consequences of dam failure may also change as development occurs within potential dam failure inundation boundaries. This potential future increase in consequences can be taken into account as part of a long-term consideration of risk.
This document provides guidelines for implementing risk-informed decision making in a dam safety program. The intended audience is Federal agencies that own or regulate dams. The guidelines could also be applied to non-federally owned or regulated dams that can impact federally owned or regulated facilities; however, this would require the cooperation and involvement of the non-Federal dam owner.
Revision ID: 6437
Revision Date: 01/24/2023