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FEMA Levee Resources Library

This page provides information specific to levee systems including risk, safety, flood hazard mapping, and accreditation. Included are basic resources, definitions, and general fact sheets, as well as technical information on levee system accreditation and mapping resources. This page is intended for the general public and State and local officials.

Levee Basics: Resources

FEMA Resources

Velva, N.D., June 26, 2011 -- Levee built around the town of Velva to hold back the overflowing Souris River.  Burleigh and Ward counties were designated a federal disaster area, opening the way for federal disaster assistance from FEMA.  Andrea Booher/FEMAGet the basics on levee systems and flood hazard mapping and levee risk through a selection of FEMA levee fact sheets, listed below. The latest information on levee-related topics can be found on the FEMA Levee Homepage. Resources designed specifically for the media are available through the Levee Resources for the Media webpage.



FEMA Fact Sheets

FEMA Levee Outreach Toolkit

FEMA has developed a Levee Outreach Toolkit to assist in local outreach efforts. The toolkit includes templated, flexible materials that local government officials, real estate, lending, insurance professionals, and others can adapt and use to effectively communicate about the flood hazards and risks in levee impacted areas and the flood insurance implications of flood hazard changes. The Levee Outreach Toolkit materials are available through the following webpages:

Other Resources

The U.S. Army Corps of Engineers St. Louis District’s Corps Concepts program features a series of online videos explaining the basics of levees and levee systems, levee inspections and other topics, that may also be helpful in outreach.

Levee Safety Resources

FEMA Resources

FEMA’s levee stakeholder information webpages contain information on levee risk and taking action to prepare for levee-related flooding: Demolition continues at the site of the mobile hospital and more trucks are lined up waiting to be loaded. Local residents in Jones, Leake, Montgomery, Simpson and Warren counties whose property was damaged by the recent storms, tornadoes and flooding in Mississippi may now apply for federal assistance, and are encouraged to apply to FEMA by calling (800) 621-3362, (TTY) (800) 462-7585, or by applying online at

Additionally, FEMA’s preparedness website,, also features critical information on disaster preparedness.

Other Resources

The American Society of Civil Engineers’ preparedness guide, So You Live Behind a Levee!, outlines the risks associated with levees and steps that can be taken to prepare for levee-related disasters. Similarly, the Association of State Floodplain Manager’s brochure, Levee Residual Risk Areas: Are You at Risk?, explains the concept of residual risk and actions that can be taken by the public to reduce  their risk. National Committee on Levee Safety features a wealth of information on levee safety, including their January 2009 report to Congress on the subject, and numerous other levee safety white papers, in addition to basic information on levees and their quarterly newsletter, Levee Safety Connections.


U.S. Army Corps of Engineers (USACE) Resources

The U.S. Army Corps of Engineers’ Levee Safety Program assesses the integrity and viability of levee systems and recommends ways to keep the public safe. Their program webpages feature reference documents, the latest Program activities, information on the USACE’s levee inspection process, and more.

The USACE’s National Levee Database contains safety information on many of the nation’s levees, featuring specific information on design, construction, and maintenance.  The NLD is the focal point for comprehensive information about our nation's levees. Authorized by Congress in 2007, the database contains information to facilitate and link activities, such as flood risk communication, levee system evaluation for the National Flood Insurance Program (NFIP), levee system inspections, floodplain management, and risk assessments. The NLD continues to be a dynamic database with ongoing efforts to add levee data from Federal Agencies, States, and Tribes

For more information about levee system evaluations for the NFIP, USACE Engineering Circular 1110-2-6067 (USACE Process for the National Flood Insurance Program Levee System Evaluation), issued August 31, 2010, comprehensively outlines the USACE’s policy for levee system evaluations performed by the USACE for FEMA NFIP accreditation of levee systems.

Levee Analysis & Mapping Approach Released

The Federal Emergency Management Agency (FEMA) released its Analysis and Mapping Procedures for Non-Accredited Levees - New Approach on July 9, 2013. Review additional information available on the FEMA Levee Analysis and Mapping Approach page.

FEMA Levee System Accreditation and Mapping Resources

FEMA Levee System Accreditation and Mapping

Webster, S.D., July 12, 2011 -- FEMA Public Assistance Coordinator Jim Russell (left) and Day County S.D. Highway Supervisor Chuck Fromelt, look over township maps reviewing damage incurred from recent flooding.FEMA does not build, own, or certify levees.

The U.S. Army Corps of Engineers (USACE) is responsible for building and maintaining USACE-owned levees and for inspecting those structures to determine their level of maintenance. States, communities, and private levee owners are responsible for maintaining and operating the levees they own according to specific design criteria. FEMA does identify, analyze, and map the flood hazards associated with levees, and depicts accreditation on Flood Insurance Rate Maps (FIRMs) for those levee systems for which the appropriate certification documentation has been submitted. Specifically, a levee system that is designed to reduce the hazard from the 1-percent-annual-chance flood may be accredited by FEMA, and areas immediately behind them mapped as a moderate-hazard zone, Zone X (shaded). In order for a levee system to be accredited, a community must provide data and documentation demonstrating that the levee system is in compliance with the requirements of the National Flood Insurance Program (NFIP) regulations cited in the Code of Federal Regulations (CFR) at Title 44, Chapter 1, Section 65.10 (44 CFR 65.10). Once FEMA determines compliance with 44 CFR  65.10 has been demonstrated, the levee system can be shown as accredited on the effective FIRM panel(s). However, just because a levee system has been accredited on the NFIP map, does not mean that people or the property behind the levee are protected – the risk of flooding may have only been reduced, not removed. Levees can fail or be overtopped by more extreme events and the flooding that follows can be catastrophic. That is why FEMA strongly recommends that residents and business owners living near all levees carry flood insurance.

FEMA Fact Sheets and Other Documentation on Levee Accreditation and Mapping

Levee-Related FEMA Guidelines and Standards

FEMA’s guidelines and standards related to levees and the accreditation process is available through the Guidelines and Standards for Flood Risk Analysis and Mapping page. These documents provide guidance on various topics relating to levee mapping, accreditation, and PALs.

Provisionally Accredited Levees (PALs)

When reasonably expected to continue to reduce the hazard from the 1-percent-annual-chance flood, levees may be provisionally accredited by FEMA in order to provide the community a reasonable time to gather the data/documentation to meet 44 CFR 65.10. Additional information on PALs is available in the following documents:

Levee System Restoration and Construction Projects

Information on levee system restoration and construction projects, including the use of Zones AR and A99 on Flood Insurance Rate Maps is available through the Levee System Construction and Restoration Mapping Projects Homepage.

Levee-Related FEMA Guidelines and Standards

FEMA’s guidelines and standards related to levees and the mapping process is available through the Guidance for Flood Risk Analysis and Mapping. These documents provide guidance on various topics relating to levee mapping, accreditation and PALs.

Levee System Construction and Restoration Projects

Information on levee system restoration and construction projects, including the use of Zones AR and A99 on Flood Insurance Rate Maps is available through the Levee System Construction and Restoration Mapping Projects Homepage.

Levee Seclusion Mapping

In March 2011, FEMA made a commitment to update the way flood hazards for non-accredited levee systems were analyzed and mapped. As a result, some ongoing Flood Insurance Rate Map (FIRM) updates that included non-accredited levee systems were delayed or otherwise impacted while FEMA developed the updated levee analysis and mapping approach. Levee seclusion mapping was developed by FEMA to allow the release of revised FIRM updates for certain communities that had non-accredited levees and whose FIRM release was delayed or otherwise impacted by the development of the levee analysis and mapping approach for non-accredited levee systems.

Specifically, seclusion mapping allows the preliminary revised FIRM to become effective by adding a “seclusion” boundary around the areas impacted by a non-accredited levee, while maintaining the flood hazard information in effect prior to the FIRM update within this boundary.

In addition to the seclusion boundary, explanatory notes are added to the FIRM and to the Flood Insurance Study (FIS) report explaining that the flood hazards within the seclusion boundary are subject to revision at a later date when the updated levee analysis and mapping approach is applied.

Levee seclusion mapping is not intended to be a long-term mapping approach and is not anticipated to be implemented on any new mapping projects initiated after July 2013, so not every FIRM update is eligible for levee seclusion mapping. Visit Levee Seclusion Mapping in the FEMA Library for more information on levee seclusion mapping, eligibility, flood hazards associated with secluded levees, secluded levees depiction on FIRMs, and other additional resources.

For More Information

Answers to the most Frequently Asked Questions are provided for the following user groups: homeowners, engineers, surveyors and architects, insurance professionals and lenders, and floodplain managers.

For additional information or assistance, contact a Map Specialist in the FEMA Map Information eXchange (FMIX) through the following methods:

  • Call (1-877) FEMA MAP (1-877-336-2627) Monday through Friday, 8:00 am through 6:30 pm (Eastern Time)
  • Email
  • Chat with a Map Specialist Monday through Friday, 9:00 am to 5:00 pm (Eastern Time)

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Additional Resources

Last Updated: 
07/31/2019 - 12:30