Federal Guidelines for Dam Safety: Hazard Potential Classification System for Dams (FEMA P-333)
Federal Emergency Management Agency, 2004
Common practice among federal and state dam safety offices is to classify a dam according to the potential impact a dam failure (breach) or mis-operation (unscheduled release) would have on upstream and/or downstream areas or at locations remote from the dam. The existing classification systems are numerous and vary within and between both the federal and state sectors. Although differences in classification systems exist, they share a common thread: each system attempts to classify dams according to the potential impacts from a dam failure or mis-operation, should it occur. The most significant problem with these various systems is the use of terms that lack clear definition. In addition, the various systems use different terminology to define similar concepts. This precludes consistency between the various federal and state agencies and understanding by the public.
This document sets forth a hazard potential classification system for dams that is simple, clear, concise, and adaptable to any agency's current system. The intent is to provide straightforward definitions that can be applied uniformly by all federal and state dam safety agencies and can be readily understood by the public. It does not establish how the system will be used, such as prescribing specific design criteria or prioritizing inspections. Those responsibilities belong to the responsible regulatory authority.
Revision ID: 5850
Revision Date: 12/16/2022