When discussing levees, there are many terms and definitions that can mean different things to different people. Here are a few terms related to levees and their U.S. Army Corps of Engineers' definition. Click here for a slide-show further explaining the definitions of levee failures and the potential sources of flooding.
Breach: A rupture, break or gap whose cause has not been determined.
Corps authority: There is no single agency with responsibility for levee oversight nationwide. The Corps has specific and limited authorities for approximately 2,000 levees nationwide.
Corps rehabilitation funding eligibility: Federally authorized and some non-federal levees may be eligible for Corps rehabilitation assistance funding if certain criteria are met.
Failure breach: A breach for which a cause of failure is known based on an investigation to determine the cause.
Levee: An earthen embankment, floodwall, or structure along a water course whose purpose is flood risk reduction or water conveyance.
Levee certification: Process under the national Flood Insurance Program used to determine how the Federal Emergency Management Agency (FEMA) will map the floodplain behind a given levee system. Certification documentation is the responsibility of the local project sponsor.
- Federally authorized levee: Typically designed and built by the Corps in cooperation with a local sponsor then turned over to a local sponsor to operate, maintain, repair and replace the levee.
- Non-federally authorized levee: Designed and built by a non-federal agency, which is responsible for the operation, maintenance, repair and replacement of the levee.
- Private or corporate-owned levee: Designed and built by a private citizen, company or other public entity, which is responsible for the operation, maintenance, repair and replacement of the levee. The Corps has no responsibility for private or corporate-owned levees.
Local responsibility: The responsibilities of local levee partners are broad and include levee safety; land use planning and development; building codes and operations, maintenance, repair, rehabilitation and replacement of the levee.
Overtopping: Water levels exceed the crest elevation of a levee and flow into protected areas. Levee may be damaged but not compromised. Flooding occurs from overflow/overwash (waves) and other sources.
Overtopping breach: A breach whose cause is known to be a result of overtopping (system exceeded). The levee has been compromised after overtopping and must be repaired to function prior to the next event.