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National Dam Safety Program Publications

The National Dam Safety Program provides a variety of publications, including:

  • Research Needs Workshop Reports
  • Technical Manuals, Guides and Reports
  • Technical Advisories
  • Safety Series Fact Sheets
  • Response and Recovery (R&R) Dam Response Operations Matrices
  • Dam Safety & Risk MAP/Flood Mapping Studies Fact Sheet Series
  • DSS-WISE Fact Sheets
  • FEMA P-1015, Technical Manual: Overtopping Protection for Dams (ZIP, 410MB)

Search for documents below, or view our pages on Federal GuidelinesNational Dam Safety Program InformationResources for the General Public, or Resources for States.

You can order publications from the FEMA Distribution Center.

Search for Dam Safety Publications

DSS-WISE™ Lite Case Studies - A State Perspective

This is a summary of how states are using Decision Support System for Water Infrastructure Security™ Lite (DSS-WISE™ Lite), a web-based, automated two-dimensional dam-break flood modeling and mapping capability, as a dam risk management tool. DSS-WISE™ Lite was developed by the National Center for Computational Hydroscience and Engineering (NCCHE), the University of Mississippi. Its development, operation, and maintenance are supported by FEMA. DSS-WISE™ Lite has been used extensively during numerous dam incidents and emergencies. FEMA reached out to several states asking for case studies of their experience with DSS-WISE and received over 100 examples. </p>

Federal Guidelines for Dam Safety Risk Management (FEMA Publication No. P-1025)

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.

Federal Guidelines for Dam Safety: Glossary of Terms (FEMA P-148)

This glossary provides a common terminology for dam safety for use within and among federal agencies. The terms are generic and applicable to all dams, regardless of size, owner, or location. The CD-ROM, FEMA 93CD, 2005, contains all of the Federal Guidelines for Dam Safety: FEMA 64; FEMA 65; FEMA 93; FEMA 94; FEMA 148; and FEMA 333.

Federal Guidelines for Dam Safety (FEMA Publication No. P-93)

These guidelines encourage strict safety standards in the practices and procedures employed by Federal agencies or required of dam owners regulated by the Federal agencies. The guidelines provide the most complete and authoritative statement available of the desired management practices for promoting dam safety and the welfare of the public. The guidelines apply to Federal practices for dams with a direct federal interest; the guidelines do not attempt to establish technical standards and are not intended to supplant or conflict with state or local government responsibilities for the safety of dams under their jurisdiction.

Federal Guidelines for Dam Safety: Earthquake Analyses and Design of Dams (FEMA Publication No. P-65)

These guidelines provide the basic framework for the earthquake design and evaluation of dams. The general philosophy and principles for each part of the framework are described in sufficient detail to achieve a reasonable degree of uniform application among the federal agencies involved in the planning, design, construction, operation, maintenance, and regulation of dams. This document includes general guidelines for specifying design earthquake loadings (for design or safety evaluation) and for performing seismic analyses for the design of new dams (for evaluating the safety of existing dams or modifying existing dams). The guidelines are presented in four parts: selection of design or safety evaluation for earthquakes; characterization of ground motions; seismic analyses of the dams and foundations; and evaluation of structural adequacy for earthquake loading. The CD-ROM, FEMA 93CD, 2005, contains all of the Federal Guidelines for Dam Safety: FEMA 64; FEMA 65; FEMA 93; FEMA 94; FEMA 148; and FEMA 333.

Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow Design Floods for Dams (FEMA Publication No. P-94)

These guidelines provide thorough and consistent procedures for selecting and accommodating inflow design floods (IDFs), the flood flow above which the incremental increase in water surface elevation downstream due to the failure of a dam or other water retaining structure no longer presents an unacceptable additional downstream threat. These guidelines are not intended to provide a complete manual of all procedures for estimating IDFs; the selection of procedures is dependent upon available hydrologic data and individual watershed characteristics.

GIS Tools in Rebuilding a State Dam Safety Program

GIS Tools in Rebuilding a State Dam Safety Program | Jeannie Eidson and Kelsy Grogan

Dam Safety Considerations For Earth Dams Following Significant Reservoir Drawdown

Dam Safety Considerations For Earth Dams Following Significant Reservoir Drawdown | James Olsen & Joels Malama

National Dam Safety Program - Strategic Plan 2012-2016 (FEMA P-916)

This Strategic Plan for the National Dam Safety Program (NDSP) for Fiscal Years (FY) 2012 through 2016 was developed on behalf of the Administrator of the Federal Emergency Management Agency (FEMA), as required by the Dam Safety Act of 2006 (33 U.S. Code [U.S.C.] § 467 et seq., as amended).

National Dam Safety Program - Year in Review 2017

For 30 years, the Federal government has used the National Dam Safety Program (NDSP) to protect Americans from dam failure. The NDSP is a partnership of the States, Federal agencies, and other stakeholders that encourages and promotes the establishment and maintenance of effective Federal and state dam safety programs to reduce the risks to human life, property, and the environment from dam related hazards.

Dam and Levee Safety and Community Resilience

Dam and Levee Safety and Community Resilience | Lewis Link

Dam Safety Awareness

Increased awareness of dams and the risks they pose is an important part of dam risk management. Hazards from dams can be triggered by severe weather events, improper operation of the dam, or regular or emergency releases of water downstream.

Risk Communication for Dams in Risk MAP

Risk communication can help increase knowledge, understanding, and awareness of dams and the risks they pose. While dams can serve many purposes, such as flood risk reduction, hydropower generation, water supply, and recreation, many people in communities near dams are unprepared to deal with the impacts of a dam failure or dam-related flooding. It is important to be aware that risk can come from many modes of failure, or even from conditions in which the dam has not failed at all.

Dam Considerations in Flood Mapping Studies

Whether for flood control, water supply, or recreation, dams play an important role in serving the community and managing a natural resource, but there are hazards and risks to consider when large volumes of water are stored. Sharing information about dams during a flood mapping study can help stakeholders obtain a more complete picture of the risks within a floodplain.

Considering the Residual Risk from Dams in Flood Risk Products

During a flood mapping project, to properly assess and communicate a complete view of the flood risk both upstream and downstream of a dam, it is critical to consider the effects of dams and their associated residual risk. Many large reservoirs are operated with outflow controls that include gates to regulate the flow through outlet structures. Dam outlet control structures can affect flow rates downstream regardless of the dam’s purpose. Even when dams perform as they are designed, there will always be a level of flood risk remaining, or “residual risk.”

South Carolina Response and Recovery Dam Response Operations Matrix

FEMA DR-4286C | This Response and Recovery (R&R) Dam Response Operations Matrix was primarily developed for stakeholder outreach, and as a reference for emergency or disaster dam-related response or recovery operations in South Carolina.

North Carolina Response and Recovery Dam Response Operations Matrix

FEMA DR-4285 | This Response and Recovery (R&R) Dam Response Operations Matrix was primarily developed for stakeholder outreach, and as a reference for emergency or disaster dam-related response or recovery operations in North Carolina.

Dam Safety Technical Advisory #1: Risk Reduction Measures for Dams

The purpose of this Technical Advisory is to help people and organizations better understand the various measures that can be taken to reduce the risks from and improve resilience to dam failure. The intended audience includes federal, state, and local officials; tribal leaders; county and city engineers, planners, and emergency managers; dam owners and operators; building and property owners near or potentially affected by a dam failure; and other interested stakeholders.

Dam Safety Technical Advisory #2: Risk Exposure and Residual Risk Related to Dams

The purpose of this Technical Advisory is to help all stakeholders better understand risk exposure, residual risk, and the potential contributing factors to risk related to living and working near a dam or within a dam inundation zone. The information is intended to help stakeholders improve emergency planning and community resilience based on informed decision making. The intended audience includes federal, state and local officials; tribal leaders; county and city planners and emergency managers; dam owners and operators; building and property owners near or potentially affected by a dam failure; and other interested stakeholders and the general public.

Dam Safety Technical Advisory #3: Dam Awareness

The purpose of this Technical Advisory is to help increase the general understanding, knowledge, and awareness of dams to enable improved planning and community resilience, among other benefits. The target audience includes emergency managers and various planners; federal, state, and local officials; tribal leaders; city and county engineers and officials; dam owners and operators; building and property owners, including homeowners associations; stakeholders who live near or downstream of dams or are affected by them; and the general public.

The National Dam Safety Program Research Needs Workshop: Seepage through Embankment Dams (FEMA 535)

This workshop report documents expert consideration of (1) potential seepage problems and solutions associated with penetrations through embankment dams, e.g., outlet works conduits; (2) filter design criteria and observed performance; (3) inspection of dams for detection of seepage problems, failure modes associated with seepage and internal erosion, and analysis of risks associated with seepage and internal erosion; (4) investigation of seepage problems and concerns at dams, including the use of geophysical techniques, and instrumentation and measurements for evaluation of seepage performance; (5) remediation of seepage problems through cutoff, reduction of flow, and collection and control of seepage, including the use of geosynthetics; and (6) impacts of the aging of seepage control and collection system components on seepage performance.

The National Dam Safety Program Research Needs Workshop: Seepage through Embankment Dams (Text Version) (FEMA 535)

Text Version: This workshop report documents expert consideration of (1) potential seepage problems and solutions associated with penetrations through embankment dams, e.g., outlet works conduits; (2) filter design criteria and observed performance; (3) inspection of dams for detection of seepage problems, failure modes associated with seepage and internal erosion, and analysis of risks associated with seepage and internal erosion; (4) investigation of seepage problems and concerns at dams, including the use of geophysical techniques, and instrumentation and measurements for evaluation of seepage performance; (5) remediation of seepage problems through cutoff, reduction of flow, and collection and control of seepage, including the use of geosynthetics; and (6) impacts of the aging of seepage control and collection system components on seepage performance.

The National Dam Safety Program Research Needs Workshop: (FEMA 536)

This workshop report documents the state of practice concerning cost-effective techniques for the enlargement, modification, inspection, monitoring, and maintenance of dam service and emergency spillways. The report discusses dam safety research needs related to dam spillways, i.e., the short-term and long-term needs of the federal and non-federal dam safety community, and recommends a course of action to address those research needs.

The National Dam Safety Program Research Needs Workshop: Spillway Gates (FEMA 537)

One of the outcomes of the Folsom tainter gate failure was the recognition of the need to revisit the issues related to gate performance and safety. This workshop report documents lessons learned from the Folsom tainter gate failure and applies those lessons across the broad spectrum of spillway gates. The report provides recommendations for future action and serves as a reference for regulatory agencies as they refine their requirements in this area.

The National Dam Safety Program Research Needs Workshop: Hydrologic Issues for Dams (Text Version) (FEMA 538)

This workshop report documents expert findings in three areas: risk analysis, standards, and meteorological needs. Risk analysis focuses on items relating to uncertainty factors that influence reservoir inflow values and the computation of the Annual Exceedance Probability (AEP) of extreme floods. Standards issues include physical factors that influence the methodology for the computation of extreme floods, including the Probable Maximum Flood (PMF). Meteorological needs focus on rainfall analysis from both the standards base analysis and a risk-based analysis, including precipitation analysis, rainfall frequency analysis, and real-time storm analysis.

The National Dam Safety Program Research Needs Workshop: Hydrologic Issues for Dams (FEMA 538)

This workshop report documents expert findings in three areas: risk analysis, standards, and meteorological needs. Risk analysis focuses on items relating to uncertainty factors that influence reservoir inflow values and the computation of the Annual Exceedance Probability (AEP) of extreme floods. Standards issues include physical factors that influence the methodology for the computation of extreme floods, including the Probable Maximum Flood (PMF). Meteorological needs focus on rainfall analysis from both the standards base analysis and a risk-based analysis, including precipitation analysis, rainfall frequency analysis, and real-time storm analysis.

The National Dam Safety Program Research Needs Workshop: Outlet Works (FEMA 539)

This report addresses (1) outlet works failure modes, including failure by seepage and piping along the outlet works conduit; (2) conduit materials, selection criteria, and construction methods, including pipe material types and their advantages, disadvantages, and appropriate applications; (3) gates, valves, and controls, including types of gates and valves and their applications; (4) energy dissipaters, including stilling basins and energy dissipating valves; (5) rehabilitation of conduits, including in-place rehabilitation and replacement; and (6) outlet works inspection, including the determination of appropriate frequency; systems, methods, and techniques; and consideration of design criteria to accommodate inspection.

The National Dam Safety Program Research Needs Workshop: Outlet Works (Text Version) (FEMA 539)

This report addresses (1) outlet works failure modes, including failure by seepage and piping along the outlet works conduit; (2) conduit materials, selection criteria, and construction methods, including pipe material types and their advantages, disadvantages, and appropriate applications; (3) gates, valves, and controls, including types of gates and valves and their applications; (4) energy dissipaters, including stilling basins and energy dissipating valves; (5) rehabilitation of conduits, including in-place rehabilitation and replacement; and (6) outlet works inspection, including the determination of appropriate frequency; systems, methods, and techniques; and consideration of design criteria to accommodate inspection.

The National Dam Safety Program Research Needs Workshop: Impacts of Plants and Animals on Earthen Dams (FEMA 540)

Several areas for future development related to the impacts of plants and animals on earthen dams are documented in this report, including (1) the development of tools to educate dam owners and engineers on how to spot problems caused by plant and animal penetrations, how to prevent these problems from occurring, and how to mitigate or repair existing problems; (2) the analysis of tools and methods for repairing animal burrows on dams; and (3) collaboration with other groups, such as federal wildlife agencies that have research programs in place.

The National Dam Safety Program Research Needs Workshop: Impacts of Plants and Animals on Earthen Dams (Text Version) (FEMA 540)

Several areas for future development related to the impacts of plants and animals on earthen dams are documented in this report, including (1) the development of tools to educate dam owners and engineers on how to spot problems caused by plant and animal penetrations, how to prevent these problems from occurring, and how to mitigate or repair existing problems; (2) the analysis of tools and methods for repairing animal burrows on dams; and (3) collaboration with other groups, such as federal wildlife agencies that have research programs in place.

The National Dam Safety Program Research Needs Workshop: Embankment Dam Failure Analysis (FEMA 541)

For this workshop, 35 national and international experts participated in discussions on research and new technology related to risk assessment, embankment dam failure, and flood routing. The experts identified 14 priority areas for research, including the updating, revision, and dissemination of the historic data set/database of dam failures; development of forensic guidelines and standards for dam safety expert use when reporting dam failures or dam incidents; creation of a forensic team that would be able to collect and disseminate valuable forensic data; identification of critical parameters for different types of failure modes; and basic physical research to model different dam parameters, such as soil properties and scaling effects, with the intent to verify the ability to model actual dam failure characteristics and extend dam failure knowledge using scale models.

The National Dam Safety Program Research Needs Workshop: Embankment Dam Failure Analysis (Text Version) (FEMA 541)

For this workshop, 35 national and international experts participated in discussions on research and new technology related to risk assessment, embankment dam failure, and flood routing. The experts identified 14 priority areas for research, including the updating, revision, and dissemination of the historic data set/database of dam failures; development of forensic guidelines and standards for dam safety expert use when reporting dam failures or dam incidents; creation of a forensic team that would be able to collect and disseminate valuable forensic data; identification of critical parameters for different types of failure modes; and basic physical research to model different dam parameters, such as soil properties and scaling effects, with the intent to verify the ability to model actual dam failure characteristics and extend dam failure knowledge using scale models.

The National Dam Safety Program Research Needs Workshop: Risk Assessment for Dams

This workshop report presents the detailed discussions of federal, state, and private sector experts on the three areas of risk assessment applications for dam safety: failure modes identification (qualitative approaches); portfolio risk assessment and index prioritization approaches (prioritization and portfolio approaches); and detailed quantitative approaches. The workshop participants recognized that stakeholders will have different information needs for their dam safety decisions. As a result, information that may play an essential role in a dam owner’s decision-making process may not be needed by a regulator who oversees the dam owner’s decision outcomes. Because the information needs of organizations vary widely, the workshop report acknowledges that it is not feasible for a single risk assessment approach to meet the needs of all organizations

The National Dam Safety Program Research Needs Workshop: Risk Assessment for Dams (Text Version)

This workshop report presents the detailed discussions of federal, state, and private sector experts on the three areas of risk assessment applications for dam safety: failure modes identification (qualitative approaches); portfolio risk assessment and index prioritization approaches (prioritization and portfolio approaches); and detailed quantitative approaches. The workshop participants recognized that stakeholders will have different information needs for their dam safety decisions. As a result, information that may play an essential role in a dam owner’s decision-making process may not be needed by a regulator who oversees the dam owner’s decision outcomes. Because the information needs of organizations vary widely, the workshop report acknowledges that it is not feasible for a single risk assessment approach to meet the needs of all organizations.

Emergency Operations Planning: Dam Incident Planning Guide

This Dam Incident Planning Guide supports state, local, tribal, and territorial emergency managers in planning for dam incidents and failures by summarizing the concepts that a community should consider when creating dam incident-specific elements of local emergency operations plans. This guide builds on the Comprehensive Preparedness Guide (CPG) 101: Developing and Maintaining Emergency Operations Plans.1 It also provides guidance for dam owners and operators on how to engage with emergency managers prior to an incident to ensure a well-coordinated response. Appendix A provides a general template for a community dam incident plan that can be adapted to meet each community’s needs.

South Carolina Dam Failure Assessment and Advisement (FEMA P-1801)

From October 1 through 5, 2015, heavy rainfall over parts of South Carolina resulted in the failure of 49 state-regulated dams, one federally regulated dam, two sections of the levee adjacent to the Columbia Canal, and many unregulated dams. In support of recovery efforts, FEMA Mitigation deployed a team to assist in the assessments of dams and provide expertise and insights to the State of South Carolina, FEMA Headquarters, FEMA Region IV, and Joint Field Office leadership.

South Carolina Dam Failure Assessment and Advisement (FEMA P-1801) General Advisories

In coordination with the South Carolina Department of Health and Environmental Control (SC DHEC) to ensure accuracy and consistency with their regulations and procedures, Recovery Advisories were developed to help dam owners in the post disaster recovery. The advisories were provided to SC DHEC for distribution to dam owners.

Pocket Safety Guide for Dams and Impoundments (FEMA P-911)

This guide was developed as a quick reference to help dam owners and others assess low hazard dams and impoundments. Uncontrolled release of a reservoir resulting from a dam failure can have a devastating effect on people and property downstream. Safely maintaining a dam is a key element in preventing dam failure and limiting the liability a dam owner could face.

Evaluation and Monitoring of Seepage and Internal Erosion (FEMA P-1032)

Internal erosion occurring at Federal (and non-Federal) embankment dams and levees poses a threat of failure and the potential risk to public safety. This document presents a summary of current Federal practices for monitoring and measuring seepage, identifying potential failure modes (PFMs) related to internal erosion, assessing risk related to internal erosion, and remediating internal erosion. While research continues into these processes, this document attempts to present the best understanding based on current Federal agency practice. Hence, very recent or new, unproven technologies are not discussed.

Selecting Analytic Tools for Concrete Dams Address Key Events Along Potential Failure Mode Paths (FEMA P-1016)

In this document, failure is considered the uncontrolled release of the reservoir. However, this may or may not always be the case given the purpose or hazard of a structure or given an agency’s requirements for a structure. How do we determine if a concrete dam can fail? Failure results from sequences of events that must follow one upon another. Because a dam cannot fail without the full chain of events, conclusively ruling out any event justifies concluding that the dam will not fail. This document introduces event trees. Event trees are pictorial representations of the sequences of events (called nodes) leading to failure. The possibility of each node occurring is evaluated by analyses. It is the experience of the authors that engineers often rush to analysis without consideration of the failure process. As a result, expensive analyses are done that are not needed, waste time, and often do not answer the question of whether a dam will fail. Examples presented are for instructional purposes only. Assumptions made, material properties used, and loadings were selected to illustrate structural analysis methods and failure modes, and are not generally applicable.

FEMA P-1014, Overtopping Protection for Dams Brochure

Federal Guidelines for Inundation Mapping of Flood Risks Associated with Dam Incidents and Failures (FEMA P-946)

The purpose of this document is to provide dam safety professionals with guidance on how to prepare dam breach inundation modeling studies and conduct mapping that can be used for multiple purposes including dam safety, hazard mitigation, consequence evaluation, and emergency management including developing Emergency Action Plans (EAPs). This guidance is intended to provide a consistent approach that can be applied across the country (2013).

Federal Guidelines for Dam Safety: Emergency Action Planning for Dams (FEMA P-64)

This document provides guidance to help dam owners, in coordination with emergency management authorities, effectively develop and exercise Emergency Action Plans (EAPs) for dams. The purpose of the guidance in this document is to meet that need. This document is an update of FEMA 64, Federal Guidelines for Dam Safety: Emergency Action Planning for Dam Owners (2004).

Filters for Embankment Dams - Best Practices for Design and Construction

This document provides procedures and guidance for best practices concerning embankment dam filter design and construction, and represents an effort to collect and disseminate current information and experience having a technical consensus. This document is intended for use by personnel familiar with embankment dams, such as designers, inspectors, construction oversight personnel, and dam safety engineers.

Technical Manual: Plastic Pipe Used in Embankment Dams (FEMA P-675)

This technical manual provides the procedures and guidance for “best practices” concerning the design, construction, problem identification and evaluation, inspection, maintenance, renovation, and repair associated with plastic pipe used in embankment dams.The manual provides in-depth analyses of loading conditions, structural design, and hydraulic design of plastic pipe, and is intended for use by personnel familiar with embankment dams, drains, siphons, and conduits, such as designers, inspectors, construction oversight personnel, and dam safety engineers.

Technical Manual: Plastic Pipe Used in Embankment Dams (FEMA P-675) (Text Version)

This technical manual provides the procedures and guidance for “best practices” concerning the design, construction, problem identification and evaluation, inspection, maintenance, renovation, and repair associated with a plastic pipe used in embankment dams. The manual provides in-depth analyses of loading conditions, structural design, and hydraulic design of plastic pipe, and is intended for use by personnel familiar with embankment dams, drains, siphons, and conduits, such as designers, inspectors, construction oversight personnel, and dam safety engineers.

Emergency Action Planning for State Regulated High-Hazard Potential Dams: Findings, Recommendations and Strategies (FEMA 608)

Preventing loss of life from dam failure is the paramount concern of the National Dam Safety Program. This concern has intensified as a result of recent disasters that have focused attention on the state of the critical infrastructure in the United States and raised questions on the safety of dams nationwide. As part of a recent initiative to promote the implementation of Emergency Action Plans at all high-hazard potential dams across the United States, FEMA has asked all of the states to adopt the applicable recommendations contained in this paper.

Emergency Action Planning for State Regulated High-Hazard Potential Dams: Findings, Recommendations and Strategies (FEMA 608) (Text Version)

Preventing loss of life from dam failure is the paramount concern of the National Dam Safety Program. This concern has intensified as a result of recent disasters that have focused attention on the state of the critical infrastructure in the United States and raised questions on the safety of dams nationwide. As part of a recent initiative to promote the implementation of Emergency Action Plans at all high-hazard potential dams across the United States, FEMA has asked all of the states to adopt the applicable recommendations contained in this paper.

Final Report on Coordination and Cooperation with the European Union on Embankment Failure Analysis (FEMA 602)

There has been an emphasis in the European Union (EU) community on the investigation of extreme flood processes and the uncertainties related to these processes. Over a 3-year period, the EU and the U.S. dam safety community (1) coordinated their efforts and collected information needed to integrate data and knowledge with U.S. activities and interests related to embankment overtopping and failure analysis; (2) used the data to improve embankment failure analysis methods; and (3) disseminated the results to the U.S. dam safety community. This final report integrates EU and U.S. research findings and results related to earthen embankment overtopping failure over the 3-year period.

Final Report on Coordination and Cooperation with the European Union on Embankment Failure Analysis (FEMA 602) (Text Version)

There has been an emphasis in the European Union (EU) community on the investigation of extreme flood processes and the uncertainties related to these processes. Over a 3-year period, the EU and the U.S. dam safety community (1) coordinated their efforts and collected information needed to integrate data and knowledge with U.S. activities and interests related to embankment overtopping and failure analysis; (2) used the data to improve embankment failure analysis methods; and (3) disseminated the results to the U.S. dam safety community. This final report integrates EU and U.S. research findings and results related to earthen embankment overtopping failure over the 3-year period.

Last updated November 12, 2020