CECW-EP-E

Pamphlet No.

1110-2-13

Department of the Army

U.S. Army Corps of Engineers

Washington, DC 20314-1000

EP 1110-2-13

28 Jun 96

Engineering and Design

DAM SAFETY PREPAREDNESS

Distribution Restriction Statement

Approved for public release; distribution is unlimited.
_____________________________________________________________________

_________

EP 1110-2-13

28 June 1996

US Army Corps

of Engineers

ENGINEERING AND DESIGN

DAM SAFETY PREPAREDNESS

ENGINEER PAMPHLET 
DEPARTMENT OF THE ARMY EP 1110-2-13

U.S. Army Corps of Engineers

CECW-EP Washington, DC 20314-1000

Pamphlet

No. 1110-2-13 28 June 1996

Engineering and Design

DAM SAFETY PREPAREDNESS

1. Purpose. This pamphlet provides general guiidance and information concerting dam safety

preparedness within the Corps of Engineers.

2. Applicability. This pamphlet applies to HQUSACE elements, major subordinate commands, districts,

laboratories, and separate field operating activities having responsibility for civil works projects.

FOR THE COMMANDER:

ROBERT H. GRIFFIN

Colonel, Corps of Engineers

Chief of Staff

.—
i

DEPARTMENT OF THE ARMY EP 1110-2-13

U.S. Army Corps of Engineers

CECW-EP Washington, DC 20314-1000

Pamphlet

No. 1110-2-13 28 June 1996

Engineering and Design

DAM SAFETY PREPAREDNESS

Table of Contents

Subject Paragraph Page Subject Paragraph Page

Chapter 1

Introduction

Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 1-1

Applicability . . . . . . . . . . . . . . . . . . . . . . 1-2 1-1

References . . . . . . . . . . . . . . . . . . . . . . . . 1-3 1-1

Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 1-1

Objective and Scope ................ 1-5 1-1

Organization of Manual . . . . . . . . . . . . . . 1-6 1-1

Chapter 2

General Considerations

Introduction . . . . . . . . . . . . . . . . . . . . . . . 2-1 2-1

History of Dam Safety . . . . . . . . . . . . . . . 2-2 2-1

Federal Guidelines for Dam Safety . . . . . 2-3 2-1

Administration of Dam Safety in

 the Corps of Engineers . . . . . . . . . . . . . 2-4 2-2

Applicable Dams . . . . . . . . . . . . . . . . . . . 2-5 2-3

Modification of Dams . . . . . . . . . . . . . . . 2-6 2-4

Regulatory Permit Program for

 Non-Federal Dams . . . . . . . . . . . . . . . . . 2-7 2-4

Chapter 3

Civil Works Project Planning and Design

Process

General . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 3-1

Problem Perception and Study 

 Authorization . . . . . . . . . . . . . . . . . . . . 3-2 3-1

Reconnaissance Phase . . . . . . . . . . . . . . . 3-3 3-1

Feasibility Phase . . . . . . . . . . . . . . . . . . . 3-4 3-1

Preconstruction Engineering and

 Design Phase . . . . . . . . . . . . . . . . . . . . . 3-5 3-1

Construction Phase . . . . . . . . . . . . . . . . . 3-6 3-2

Operation and Maintenance Phase . . . . . 3-7 3-2

Turnover of Completed Dam Projects

 to Local Sponsors . . . . . . . . . . . . . . . . . . 3-8 3-2

Chapter 4

Operation and Maintenance

General . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 4-1

Operation and Maintenance Manual . . . . 4-2 4-1

Instrumentation and Monitoring . . . . . . . 4-3 4-1

Initial Reservoir Filling . . . . . . . . . . . . . . 4-4 4-1

Periodic Inspection and Continuing

Evaluation . . . . . . . . . . . . . . . . . . . . . . . 4-5 4-2

Reporting Distress . . . . . . . . . . . . . . . . . . 4-6 4-3

Chapter 5

Rehabilitation and Modification of Dams

Dam Safety Rehabilitation . . . . . . . . . . . 5-1 5-1

Major Rehabilitation Program . . . . . . . . . 5-2 5-1

Dam Safety Assurance Program . . . . . . . 5-3 5-1

Procedural Requirements . . . . . . . . . . . . 5-4 5-3

Chapter 6

Emergency Action Plans (EAP)

General . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1 6-1

Scope of Emergency Action Plan . . . . . . 6-2 6-1

Components of Emergency Action Plan 6-3 6-1

Number of Emergency Action Plans 

Required . . . . . . . . . . . . . . . . . . . . . . . . 6-4 6-3

Emergency Action Plan Exercises . . . . . 6-5 6-4

Chapter 7

Training

Overview . . . . . . . . . . . . . . . . . . . . . . . . . 7-1 7-1
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Subject Paragraph Page Subject Paragraph Page

Training Program for Operations 

and Maintenance Personnel . . . . . . . . . 7-2 7-1

Corps of Engineers Training Course

on Dam Safety . . . . . . . . . . . . . . . . . . . 7-3 7-1

Training Aids for Dam Safety . . . . . . . . 7-4 7-1

Appendix A

References

Appendix B

Glossary

Appendix C

Design

Introduction . . . . . . . . . . . . . . . . . . . . . . . C-1 C-1

Design Review . . . . . . . . . . . . . . . . . . . . C-2 C-1

Instrumentation Plan . . . . . . . . . . . . . . . . C-3 C-1

Coordination Between Design and 

Construction . . . . . . . . . . . . . . . . . . . . . C-4 C-2

Appendix D

Construction

General . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1 D-1

Construction/Design Interface . . . . . . . . D-2 D-1

Problems to Watch for During 

Construction . . . . . . . . . . . . . . . . . . . . . D-3 D-1

Obtaining Quality Construction . . . . . . . D-4 D-2

Construction Records and Reports . . . . . D-5 D-2

Appendix E

Research and Development

Introduction . . . . . . . . . . . . . . . . . . . . . . . E-1 E-1

Dam Safety Research in the Corps of

Engineers . . . . . . . . . . . . . . . . . . . . . . . E-2 E-1

Dam Safety Research by Other

Federal Agencies . . . . . . . . . . . . . . . . . E-3 E-2

Coordination Among Federal Agencies . E-4 E-2

Transfer and Integration of New

Technology . . . . . . . . . . . . . . . . . . . . . E-5 E-2
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1-1

Chapter 1

Introduction

1-1. Purpose

This pamphlet provides general guidance and

information concerning dam safety preparedness within

the Corps of Engineers.

1-2. Applicability

This pamphlet applies to HQUSACE elements, major

subordinate commands (MSC), districts, laboratories,

and separate field operating activities having

responsibility for civil works projects.

1-3. References

Required and related references are listed in Appendix

A.

1-4. Glossary

Abbreviations and terms which may not be familiar to

the reader are defined in Appendix B.

1-5. Objective and Scope

The objective of this pamphlet is to provide necessary

background information, a detailed summary of

regulations and guidelines and appropriate references

pertaining to dam safety. This pamphlet will assist

USACE elements in their preparation for and

implementation of the USACE Dam Safety Program.

While it is intended for internal use, portions are

applicable for use in dam safety support provided to

Army, Air Force and Navy installations.

1-6. Organization of Manual

General considerations in dam safety, civil works

project process, operation and maintenance,

rehabilitation of dams, emergency action plans (EAP),

and training are covered in Chapters 2 to 7,

respectively. Design, construction, and research and

development, as related to dam safety, are covered in

Appendixes C to E, respectively.
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2-1

Chapter 2

General Considerations

2-1. Introduction

Although it is impossible to quantify the overall safety

of a dam, the way to achieve maximum dam safety is

well understood, i.e., to apply the utmost care and

competence to every aspect of design, construction,

operation, and maintenance. Therefore, the most

important prerequisite for safety of dams is the

professional competence of persons associated with the

dam over its life span. A dam with a record of safe

performance may still experience failure due to

undetected deficiencies in the dam or in the foundation.

Dam safety must take precedence over all other

considerations (International Commission on Large

Dams 1987; National Research Council 1985; Jansen

1983, 1988b). 

2-2. History of Dam Safety

a. Early development of dams. History indicates that dams have been a vital part of civilization for

more than 5,000 years. Dams were constructed by the

early settlers in the United States in the 1600's to

provide water supply and power gristmills and

sawmills. The oldest Corps of Engineers dams are six

lock and dams on the Green and Kentucky Rivers built

between 1836 and 1844 (Reed 1987, Walz 1990a). 

b. Dam safety. Although construction of dams

dates back many years, the history of dam safety covers

a much shorter time span. Only a limited number of

states had any type of law regulating dam safety prior

to 1900. The failure of the South Fork Dam at

Johnstown, Pennsylvania, in 1889 resulting in 2,209

deaths had limited influence on the dam safety

programs. California initiated a dam safety program

following failure of the St. Frances Dam in 1928. Failures of the Buffalo Creek Dam in West Virginia and

the Canyon Lake Dam in South Dakota in 1972

contributed to Congress passing "The National Dam

Inspection Act" in 1972. Failure of Teton Dam in

Idaho in 1976 was followed by "The Reclamation

Safety of Dams Act" in 1977. Failure of the Laurel

Run Dam in Pennsylvania and the Kelly Barnes Dam in

Georgia in 1977 set in motion the development of the

"Federal Guidelines for Dam Safety" issued in 1979 by

the Federal Coordinating Council for Science,

Engineering, and Technology (FCCSET) (discussed in

paragraph 2-3) (Federal Emergency Management

Agency 1979). In 1979, President Carter created the

Federal Emergency Management Agency (FEMA) and

directed Federal agencies to adopt and implement the

Federal Guidelines for Dam Safety and report their

progress to FEMA on a biennial basis. In 1980, the

Interagency Committee on Dam Safety (ICODS) was

formed to coordinate Federal activities and work with

the states to ensure implementation of dam safety

practices. The Corps of Engineers is the Department of

Defense representative on ICODS. In 1984, the

Association of State Dam Safety Officials (ASDSO)

was organized to provide a forum for the exchange of

information and ideas on dam safety and to foster

interstate cooperation (Association of State Dam Safety

Officials 1989). Nongovernment agencies actively

dealing with dam safety include the International

Commission on Large Dams (ICOLD) and its United

States affiliate, the United States Committee on Large

Dams (USCOLD) and the Electric Power Research

Institute (EPRI) (Colorado Division of Disaster

Emergency Services 1987; Tschantz 1982; Reed 1987;

Walz 1990a; Wiseman 1987; Jansen 1988a;

Government Accounting Office 1977, 1978; Duscha

1984, 1986, 1990). 

2-3. Federal Guidelines for Dam Safety

a. In 1977, President Carter issued a

memorandum directing three actions:

(1) That all Federal agencies having responsibility for dams conduct a thorough review of their

practices which could affect the safety of these

structures and report their findings to the FCCSET.

(2) That FCCSET prepare the "Federal Guidelines for Dam Safety" for use by all Federal agencies.

(3) That ICODS be established to promote and

monitor Federal and state dam safety programs.

b. In 1979, the "Federal Guidelines for Dam

Safety" was published, and ICODS was given oversight
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2-2

responsibility for dam safety. The key management

practices outlined in these guidelines are as follows

(Federal Emergency Management Agency 1979):

(1) Establish a Dam Safety Officer and appropriate staff.

(2) Maintain an updated inventory of dams.

(3) Document design criteria and construction

activities.

(4) Prepare initial reservoir filling plans and

reservoir regulation criteria.

(5) Prepare operation and maintenance instructions and document activities.

(6) Maintain a training and awareness program.

(7) Prepare and maintain EAPs for each dam. 

 

(8) Establish a program of periodic inspections

and evaluation of dams.

(9) Monitor and evaluate the performance of

each dam and appurtenant structure and provide

remedial construction as necessary.

2-4. Administration of Dam Safety in the

Corps of Engineers

a. Dam safety at HQUSACE. In February

1980, the Chief of Engineers appointed the Chief of

Engineering Division, Directorate of Civil Works, as

the HQUSACE Dam Safety Officer. The Dam Safety

Officer chairs a standing committee composed of

individuals having assigned responsibilities for dam

safety (ER 1110-2-1156). The Corps' Dam Safety

Officer is also the Corps' member of FEMA's ICODS

(Federal Emergency Management Agency 1988b). 

b. Dam safety organization. The Corps of

Engineers maintains a decentralized organization of

three levels. Each level is staffed with qualified and

experienced personnel in areas of design, construction,

and operations of dams and appurtenant structures.

Each level has a Dam Safety Officer and organization

as follows (ER 1110-2-1156):

(1) HQUSACE.

(a) Organization. The standing dam safety

committee members are as follows:

 Chief, Engineering Division, Directorate of

Civil Works, Chairman.

 Chief, Engineering Division, Directorate of

Military Programs.

 Chief, Operations, Construction and

Readiness Division, Directorate of Civil

Works.

 Chief, Geotechnical and Materials Branch,

Engineering Division, Directorate of Civil

Works.

 Chief, Hydraulics and Hydrology Branch,

Engineering Division, Directorate of Civil

Works.

 Chief, Structures Branch, Engineering

Division, Directorate of Civil Works.

 Chief, Electrical and Mechanical Branch,

Engineering Division, Directorate of Civil

Works.

 Chief, Construction Branch, Operations,

Construction and Readiness Division,

Directorate of Civil Works.

 Chief, Policy Development Branch, Policy

Review and Analysis Division, Directorate

of Civil Works.

(b) Responsibilities. The Dam Safety Officer is

responsible for ensuring that the Corps of Engineers

maintains a proactive dam safety program and is implementing the Federal Guidelines for Dam Safety (Federal

Emergency Management Agency 1979) in policy and

practice and other duties as described in ER 1110-2-

1156. The committee periodically reviews and

evaluates design, construction, operation, maintenance,

and rehabilitation programs to improve internal practices
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2-3

related to dam safety; reviews the status of EAPs and dam safety training; and reviews research and

development programs to ensure that the latest

technology receives consideration and evaluation. The

committee meets at least semi-annually and makes

periodic inspections and field visits as necessary. The

committee ensures that the inventory of dams is current

and adequately maintained and reviews research and

development programs to ensure that the latest

technologies related to dam safety receive consideration

and evaluation (ER 1110-2-1156). 

(2) Major Subordinate Commands (MSC).

(a) Organization. The MSC Dam Safety Officer

is the Director of Engineering and Technical Services.

The standing committee contains the chiefs of the same

disciplines as that in HQUSACE. 

(b) Responsibilities. The MSC Dam Safety

Officer and committee are responsible for quality

assurance coordination and implementation of the dam

safety program within the MSC. The committee will

conduct a minimum of two meetings per year. Their

responsibilities include establishing dam safety related

work priorities within the MSC, monitoring the status of

EAPs, ensuring dam safety training is being conducted,

ensuring that adequate data are submitted for the

inventory of Corps dams, and conducting dam safety

exercises (see ER 1110-2-1156). 

(3) District Commands.

(a) Organization. The District Dam Safety

Officer will be the Chief, Engineering Division. The

standing committee will comprise the same disciplines

as that in the MSC. However, the Dam Safety Officer

may be located in a district responsible for the technical

aspects of projects located within another districts

boundaries (should a district organization not include an

engineering division).

(b) Responsibilities. The District Dam Safety

Officer and committee are responsible for the execution

of the dam safety program. A minimum of two

meetings will be held annually. Responsibilities include

establishing a public awareness program with

information at each project and coordination with

downstream local interests, monitoring and evaluating

the performance of all dams and appurtenant structures
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2-4

and recommending remedial measures when necessary, establishing the priority of dam safety related work,

conducting dam safety training, and ensuring that each

dam has an adequate surveillance plan (ER 1110-2-

1156).

2-5. Applicable Dams

a. Dam involvement. The Corps of Engineers

involvement in dams can be categorized as follows

(ER 1110-2-1156, Federal Emergency Management

Agency 1992a):

(1) Dams which the Corps has designed, constructed, operates, and maintains. Ownership remains

with the Corps of Engineers.

(2) Dams which the Corps has designed and constructed but are owned, operated, and maintained by

others.

(3) Dams that are designed, constructed,

operated, maintained, and owned by others in which

flood control storage has been provided at Federal

expense under the authority of the 1944 Flood Control

Act.

(4) Dams for which the Corps has issued permits

under its regulatory authority.

(5) Dams inspected and evaluated by the Corps

under the authority of the National Program for the

Inspection of Non-Federal Dams, PL 92-367.

b. Dam safety. In category 1, the Corps of

Engineers has a definite responsibility for dam safety.

For dams in category 2, the primary responsibility for

dam safety is with the agency or sponsor which accepts

the project. The Corps' responsibility in this case is a

supporting consultant role. In category 3, the Corps

should participate in inspections to ensure that the

Federal flood control interest is being properly

maintained. For categories 4 and 5, the Corps has no

responsibility for dam safety (ER 1110-2-1156, Federal

Emergency Management Agency 1992a).

2-6. Modification of Dams
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28 Jun 96

2-5

a. Programs. The bulk of Corps of Engineers

dams are over 30 years old, and many dams are over

60 years old. Aging structures and advances in

technology impact on the safety of dams and require

detailed reevaluation and, in some cases, modification.

Rehabilitation of Corps of Engineers dams is

accomplished through four programs (ER 1110-2-

1155, ER 1130-2-417, ER 1165-2-119, Federal Emergency Management Agency 1992b, Walz 1990a):

(1) Major Rehabilitation Program. This

program allows significant, costly, one-time structural

rehabilitation or major replacement work. This work

restores the project to its original condition to serve as

originally intended. Work under the Major

Rehabilitation Program includes dams, locks,

powerhouses, and breakwaters (ER 1130-2-417).

(2) Dam Safety Assurance Program. This

provides for modification of completed dams when

deemed necessary for safety purposes due to new

hydrologic or seismic data or changes in the state-ofthe-art design or construction criteria. This program is

under the authority of Section 1203 of the Water

Resources Development Act of 1986 (PL 99-662) and

permits the project to function effectively as originally

intended. Examples of work under this program

include enlarging existing facilities or constructing new

facilities to provide for modifications resulting from

new hydrologic or seismic data or changes in state-ofthe art design or construction criteria deemed necessary

for safety purposes. 

(3) Modifications to completed projects.

Completed Corps projects are observed and monitored

to ascertain whether they continue to function in a

satisfactory manner and whether potential exists for

better serving the public interest. When it is found that

changes in a completed project may be desirable,

investigations are undertaken to document the need for

and feasibility of project modifications. To the extent

possible, modifications to completed projects are

accomplished under existing authorities. Significant

modifications to completed projects involving new

Federal construction or real estate acquisition in order

to serve new purposes, to in crease the scope of 

services of authorized purposes beyond that intended

at the time of project construction, or to extend services

to new beneficiaries, require authorization by Congress.

Additional information including eligible works, local

protection projects, justification and cost sharing, and

multiple purpose projects is given in ER 1165-2-119. 

(4) Operation and maintenance authority. To

properly operate the project or minimize maintenance,

reasonable changes and additions to facilities, within the

project boundaries, are made as needed as part of the

Corps' operations and maintenance program (ER 1165-

2-119). Operation and maintenance are discussed in

detail in Chapter 4.

b. Reporting sequence. Under the Major

Rehabilitation and Dam Safety Assurance Programs,

investigations are conducted and reports prepared to

determine the need for and scope of remedial measures,

and to form the basis for obtaining construction funds.

Reports are followed by more detailed investigations

which are reported in design memoranda. The design

memoranda form the basis for preparing plans and

specifications for the remedial work. More detail

regarding the Major Rehabilitation and Dam Safety

Assurance Programs is given in Chapter 5.

2-7. Regulatory Permit Program for NonFederal Dams

a. Dams and dikes. Section 9 of the River and

Harbor Act of March 3, 1899, charges the Chief of

Engineers and the Secretary of the Army to regulate the

construction of any dam or dike across any navigable

water of the United States. The term "navigable waters

of the United States" means those waters of the United

States that are subject to the ebb and flow of the tide

shoreward to the mean high water mark (mean higher

high water mark on the Pacific coast) and/or those

presently used or have been used in the past or may be

susceptible to use to transport interstate or foreign

commerce. The term "dike or dam" means any

impoundment structure that completely spans a

navigable water of the United States and that may

obstruct interstate waterborne commerce. The term does

not include weirs. Dams and dikes in navigable waters

of the United States also require Department of the

Army (DA) permits under Section 404 of the Clean

Water Act of 1977, as amended (33 U.S.C. 1344). (U.S.

Army Corps of Engineers, Office of the Chief of
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2-6

Engineers 1977). Processing a DA application under

Section 9 will not be completed until the approval of

the United States Congress has been obtained if the

navigable water of the United States is an interstate

water body, or until the approval of the appropriate

state legislature has been obtained if the navigable

water of the United States is an intrastate water body

(i.e., the navigable portion of the navigable water of the

United States is solely within the boundaries of one

state).

b. Dredged or fill material. Section 404 of the

Federal Water Pollution Control Act Amendments of

1972 charges the Secretary of the Army, acting through

the Chief of Engineers, to regulate the discharge of

dredged or fill material in the waters of the United

States. The construction of dams, dikes, etc., is

considered to be a discharge of fill material under

Section 404. On March 27, 1975, the U.S. District

Court for the District of Columbia directed the Corps 

of Engineers to extend its responsibility to regulate the

discharge of dredged or fill material under Section 404

to all waters of the United States (including territorial

seas) and to revise its regulation accordingly. The term

"waters of the United States" is a much broader term

than "navigable waters of the United States." A final

regulation was published on July 19, 1977 (U.S. Army

Corps of Engineers, Office of the Chief of Engineers

1977). 

c. Documentation for safety. Safety is one of

the factors considered in reaching public interest

decisions on applications for permits. The applicant for

a permit to construct a dam is required to furnish

documentation in order that the Corps may verify that

the proposed dam has been designed for safety. No

specific design specification or criteria are prescribed,

and no independent detailed engineering reviews are

performed. Further information on permit regulation

and dam safety is given in Permit Regulation 33 Code

of Federal Regulation 320.4(k) (U.S. Army Corps of

Engineers, Office of the Chief of Engineers 1977).
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3-1

Chapter 3

Civil Works Project Planning and

Design Process

3-1. General

The civil works planning and design process for a new

dam is continuous, although the level of intensity and

technical detail varies with the progression through the

different phases of project development and

implementation. The phases of the process are

reconnaissance, feasibility, preconstruction engineering

and design (PED), construction and finally the

operation, maintenance, repair, replacement and

rehabilitation (OMRR&R). A brief description is given

below. For more detailed guidance regarding each

phase, refer to ER 1110-2-1150.

3-2. Problem Perception and Study

Authorization 

The typical civil works project has its beginning when

a problem is perceived or experienced which is beyond

the capability of local interests to alleviate and therefore

Federal assistance is requested. At the request of one

of its members, Congress may authorize a study of the

problem (ER 1105-2-100).

3-3. Reconnaissance Phase 

A reconnaissance study is conducted to determine

whether or not the problem has a solution acceptable to

local interests for which there is a Federal interest and

if so whether planning should proceed to the feasibility

phase. The reconnaissance study is Federally funded

and is limited to 12 months with extension to

18 months under unusual circumstances. During the

reconnaissance phase, engineering assessments of

alternatives are made to determine if they will function

safely, reliably, efficiently and economically. Each

alternative should be evaluated to determine if it is

practical to construct, operate, and maintain. Several

sites should be evaluated and preliminary designs

prepared for each site for cost estimating purposes.

These preliminary designs should include the dam, the

foundation for the dam and appurtenant structures and

the reservoir rim. The reconnaissance phase consists

of preparing and reviewing proposed project plans,

structuring the project features into the code of accounts,

developing preliminary cost estimates, holding a

Reconnaissance Review Conference (RRC) with a

Technical Review Conference (TRC), if appropriate,

and developing the engineering effort and budget

required for the feasibility phase and the Initial Project

Management Plan (IPMP). The reconnaissance phase

ends with certification of the reconnaissance report.

3-4. Feasibility Phase 

A feasibility study is conducted to investigate and

recommend a solution to the problem based on technical

evaluation of alternatives and includes a baseline cost

estimate and a design and construction schedule which

are the basis for congressional authorization. The

feasibility study is cost-shared with the local sponsor

and should be completed in 3 to 4 years. All of the

project OMRR&R and dam safety requirements should

be identified and discussed with the sponsor and State

during the feasibility phase. A turnover plan (discussed

in paragraph 3-1h), for non-Federal operated dams, that

establishes a definite turnover point of the dam to the

sponsor should be documented in the IPMP and in the

Feasibility Report (ER 1105-2-100).

3-5. Preconstruction Engineering and Design

Phase

The PED phase is conducted to verify, complete and

document detailed design studies of a project as

authorized or proposed with the Feasibility Report.

Design costs for the PED phase are shared in the same

percentage as construction. During the PED phase,

which generally requires a period of about 2 years,

activities necessary to ready the project for construction

including preparation of plans and specifications (P&S)

for the first construction contract are completed. It may

be determined during the PED phase that a General

Design Memorandum (GDM) or General Reevaluation

Report (GRR) is necessary because the project has

changed substantially since administration review of the

feasibility report (with engineering appendix) or

authorization, the project was authorized without a

feasibility report, there is a need to readdress project

formulation, or there is a need to reassess project plans

due to changes in administration policy (ER 1110-2-

1150 will be followed).
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3-2

3-6. Construction Phase 

This phase not only involved the actual construction of

the project features, but includes design and

preparation of P&S for subsequent construction

contracts, review of selected construction contracts, site

visits, support for claims and modifications,

development of operation and maintenance (O&M)

manuals, and preparation and maintenance of as-built

drawings (ER 1110-2-1150).

3-7. Operation and Maintenance Phase

The project is operated, inspected, maintained, repaired,

and rehabilitated by either the non-Federal sponsor or

the Federal government, depending upon the project

purposes and the terms of the Project Cooperation

Agreement (PCA). For PCA projects and new dams

turned over to others, the Corps needs to explain up

front the O&M responsibilities, formal inspection

requirements, and responsibilities to implement dam

safety practices. 

3-8. Turnover of Completed Dam Projects to

Local Sponsors 

As a result of the Water Resources Development Act of

1986, a number of flood control and multipurpose 

dams have been authorized subject to the provision that

the local sponsor is responsible for OMRR&R (see

ER 1165-2-131). All project OMRR&R and dam 1

safety requirements must be identified and discussed

with the local sponsor during the feasibility phase and

documented in the IPMP and Feasibility Report. The

local sponsor must comply with all State and Federal

dam safety requirements. As the project design

develops and the O&M manual is prepared, the sponsor

should provide input and review the draft document.

The sponsor should be made aware of its responsibilities

for providing an adequate operational and technical staff

or appropriate engineering services contract for project

security, performance data, and timely remedial

measures as required. The turnover of the project to the

sponsor will occur immediately after the first periodic

inspection. The sponsor must be made aware that after

transfer of the project, the Corps is in a supporting role

with respect to dam safety and will only participate in

inspections and review performance data. 

__________________________________

 Guidance on policy and procedures for the turnover of completed 1

dam projects to local sponsors is given in Policy Guidance Letter

No. 39, "Responsibilities of the Corps of Engineers and Local

Sponsor to Ensure Safe Operation, Maintenance, Repair,

Replacement and Rehabilitation for Flood Control and Multipurpose

Dams Constructed Under the Provisions of PL 99-662," dated

13 November 1992.
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4-1

Chapter 4

Operation and Maintenance

4-1. General

Problems may occur following many years of troublefree operation of a dam. This is particularly so for flood

control dams which may not be tested by a significant

percentage of the maximum head for many years. Also,

any period of prolonged severe storming or severe operation such as rapid drawdown warrants additional

attention during and immediately after the operation.

This is particularly true for control structures such as

spillways, conduits, channels, and associated machinery.

Another category of higher risk involves those dams of

advanced age which may be progressively deteriorating.

Rigorous and continuous vigilance, checking, and

inspection, for as long as the dam is operational, are

necessary for dam safety (James 1990, International

Commission on Large Dams 1987, Morrison-Knudsen

Engineers 1986, Schurer 1988). Dam operations

management policy is covered in ER 1130-2-419.

4-2. Operation and Maintenance Manual

The O&M manual is prepared during the construction

phase. The purpose of the O&M manual is to provide

guidance and instructions to project personnel for proper

operation and maintenance of the facility. A general

outline for the O&M manual is given in Appendix I to

ER 1130-2-304. The O&M manual contains a narrative

summary of the critical features of the dam including

design features with safety limits, the more probable

failure modes that could lead to structure failure, and a

history of problems and how they could adversely affect

the structure under stress (ER 1130-2-419). 

4-3. Instrumentation and Monitoring

All Corps of Engineers dams are required to have an

adequate level of instrumentation to enable the designers

to monitor and evaluate the safety of the structure during

the construction period and under all operating

conditions and furnish data on behavior for application

to future designs. Eachstructureisprovided with minimum

instrumentation to measure hydrostatic pressure,

embankment seepage, and foundation underseepage

and displacement of major elements of the structure.

Strong motion accelerometers are installed in

structures located in seismic regions. In the case of

older structures, which were designed using criteria

that have been revised due to changes in the state-ofthe-art, instrumentation provides most of the data

necessary to evaluate the safety of the structure with

respect to current standards and criteria. After a

project has been operational for several years,

scheduled maintenance, repair, and replacement of

instrumentation are included in the normal plan of

operation (ER 1110-2-110). Detailed information on

instrumentation for earth and rockfill dams is given in

EM 1110-2-2300 and EM 1110-2-1908. Information

on instrumentation for concrete dams is given in

EM 1110-2-2200 and EM 1110-2-4300 (see also

Lindsey et al. 1986, Keeter et al. 1986, Currier and

Fenn 1986, and O'Neil 1989). Full reliance is not

placed on instrumentation to forecast unsatisfactory

performance, since it is impractical to install enough

instrumentation to monitor every possible problem

area. An extremely important adjunct to an adequate

instrumentation program is visual observation to

determine evidence of distress (Duscha 1982). Project

personnel receive extensive training in basic

engineering considerations pertaining to major

structures, with procedures for surveillance,

monitoring, and reporting of potential problems, and

with emergency operations (discussed in Chapter 7).

4-4. Initial Reservoir Filling

a. General. The "initial reservoir filling" is

defined as a deliberate impoundment to meet project

purposes and is a continuing process as successively

higher pools are attained for flood control projects.

The initial reservoir filling is the first test of the dam to

perform the function for which it was designed. In

order to monitor this performance, the rate of filling

should be controlled to the extent feasible, to allow as

much time as needed for a predetermined surveillance

program including the observation and analysis of

instrumentation data (Duscha and Jansen 1988). A

DM on initial reservoir filling has been required for all

new Corps of Engineers reservoir projects since

1979. 
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4-2

b. Design memorandum. As a minimum, the

DM on initial reservoir filling will include:

(1) The preferred filling rate and the available

options to control the rate of reservoir rise.

(2) The surveillance necessary to detect most

likely occurring problems.

(3) A plan for reading the instruments and

evaluating the data.

(4) A plan for inspecting the dam and down

stream areas.

(5) Instructions for observers on conditions that

require immediate attention of personnel authorized to

make emergency decisions.

(6) An emergency plan listing responsibilities,

name, and/or positions, telephone numbers and radio

frequencies to be used.

c. Existing Corps reservoir projects. Existing

operational projects, where the maximum pool (top of

flood pool) has not been experienced, will be reviewed

for compliance with requirements as outlined in

paragraph 4-4.b. For those conditions where

contingency plans have not been documented and

potential danger exists due to filling and/or impounded

storage, a report is required outlining those plans. The

document may be titled "Flood Emergency Plan"

providing that additional initial filling requirements are

deemed not to have significant potential impacts on the

safety of the structure (EM 1110-2-3600). 

4-5. Periodic Inspection and Continuing

Evaluation

a. General. A formal program for periodic

inspection and continuing evaluation of completed Corps

of Engineers projects was established in 1965. Under

this program, structures whose failure or partial failure

would endanger the lives of the public or cause

substantial property damage are periodically evaluated to

ensure their structural safety, stability, and operational

adequacy. Inspections and evaluations are performed by

teams of experienced design, construction, and

operations engineers. The evaluations are aided by

instrumentation programs (Duscha 1982).

Instructions for periodic inspection and continuing

evaluation of dams are given in ER 1110-2-100.

Additional information on inspection of dams is

available (Federal Emergency Management Agency

1979, Colorado Division of Disaster Emergency

Services 1987, Reed 1987). The periodic inspection

program has one potentially dangerous aspect in that

engineers might be tempted to place too much reliance

on it and assume that a project once inspected has a

guarantee of safety until the next inspection. The

thorough occasional inspection is invaluable but

cannot take the place of day-to-day observation by

operating personnel for detection of potentially

dangerous problems at an early and repairable stage

(James 1990). 

b. Scope of inspections. Corps of Engineers

civil works structures such as dams, powerhouses, and

appurtenant dam structures (intake and outlet works,

spillways, and tunnels) will be periodically inspected

in accordance with procedures in Appendix A of

ER 1110-2-100 to detect conditions of significant

distress or operational inadequacy. 

c. Frequency of inspections. The first

periodic inspection is carried out immediately after

topping out and prior to impoundment of the pool for

new earth and rock-fill dams. The initial inspection of

concrete dams is accomplished immediately prior to

impoundment of reservoir water. The second

inspection for new earth and rock-fill dams is made at

a reasonable stage of normal operating pool. The

second inspection of concrete dams is made when the

reservoir water attains the normal operating pool, and

in either case no later than one year after initial

impoundment has begun. Subsequent inspections for

earth and rock-fill dams and concrete dams are made

at one-year intervals for the following three years, at

two-year intervals for the next four years and then

extended to five-year intervals if warranted by the

results of the previous inspections (ER 1110-2-100).

d. Procedure. A systematic plan is

established for the inspection of features related to the

safety and stability of the structure and to the

operational adequacy of the project. Operational

adequacy means the inspecting, testing, operating, and

evaluation of those components of the project whose
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4-3

failure or failure to operate properly would impair the

operational capability and/or usability of the structure.

These components include, but are not limited to:

(1) Flood and outlet control gates (including flood

gates in levees and flood walls).

(2) Navigation lock gates and valves.

(3) Emergency closure gates. 

(4) Associated hoists and operating machinery

(including safety devices such as limit switches and failsafe interlocks).

(5) Flood control pumps and related equipment.

(6) Cathodic protection systems. 

Details concerning the systematic inspection plan are

given in Appendix A of ER 1110-2-100.

e. Reports.

(1) Pre-inspection brochure. A technical

brochure is prepared in advance of each project

inspection to familiarize inspection team members with

general features of the project. This brochure includes a

technical summary of the structural, material, and

foundation conditions; instrumentation data; and a list of

the deficiencies found in previous inspections, if

pertinent, and the status of remedial actions

recommended. Also, the brochure should include, as

appropriate, pertinent project data, layout and typical

section drawings, summaries of subsurface soil profiles

and boring logs, and the checklist developed for

conducting the inspection (ER 1110-2-100, Duscha and

Jansen 1988).

(2) Initial and subsequent reports. A condition

report will be prepared to present the results of each

general project inspection. Report No. 1 (report of initial

inspection) will provide a general project description and

present the results of the initial inspection. Reports of

subsequent inspections will be supplementary to the

initial report and will focus on changed conditions noted

since the previous inspection. A status report on

recommended remedial measures not completed prior to

approval of the previous inspection report will also be

included (ER 1110-2-100, Duscha and Jansen 1988).

4-6. Reporting Distress

a. Guidance. Evidence of distress at, or potential failure of, dams is to be reported in accordance

with the guidance set forth in ER 1110-2-101.

Evidence of distress will be immediately reported to

the district office. Where engineering evaluation of

the evidence of distress indicates the need for

immediate remedial action, the district commander

will immediately report such conditions through

command channels to the HQUSACE Dam Safety

Officer who is the Chief of the Engineering Division,

Directorate of Civil Works. Each USACE Command

will also establish procedures for notification of the

major subordinate command and district Dam Safety

Officer and coordination of all information with their

counterparts in the Emergency Management element.

The HQUSACE Dam Safety Officer will notify the

Director of Civil Works, and the Commander,

USACE. If the HQUSACE Dam Safety Officer

cannot be contacted, the reporting field office will

follow the notification sequence as outlined in

Appendix A of ER 1110-2-101. 

b. Examples. Examples of evidence of distress

include, but are not limited to:

(1) Significant sloughs, settlement, or slides in

embankments such as earth or rockfill dams, urban

levees, and bridge abutments or slopes of spillway,

channels, locks, and dam abutments. 

(2) Evidence of piping, muddy water boils in

the area of a structure such as embankments,

abutments, dam monoliths, lock walls, or cofferdams.

(3) Abnormal increase or decrease of flow

from foundation drains, structural joints, or face drains

of concrete dams.

(4) Any increase in seepage quantities through

or under embankments or in abutments.

(5) Any increase or decrease in pore water

pressure in either embankments or their foundations or

abutments.

(6) Any increase or decrease in uplift pressures

under concrete structures.
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4-4

(7) Unusual vertical or horizontal movement or

cracking of embankments or abutments.

(8) Significant cracking of mass concrete

structures either during construction or after completion.

(9) Sinkholes or localized subsidence in the foundation of or adjacent to embankments or other structures.

(10) Excessive deflection, displacement, or

vibration of concrete structures (e.g. tilting or sliding of

intake towers, bridge piers, lock wall, floodwalls).

(11) Erratic movement, binding, excessive deflection, or vibration of outlet and spillway gates.

(12) Significant damage to any structure (e.g.,

barge damage to bridge piers or lock walls or ice flow

damage to intake towers and access bridge piers).

(13) Significant damage to, or changes in, structures, foundations, reservoir levels, groundwater conditions, and adjacent terrain as a result of seismic events of

local or regional areas. Special inspections of such

damages will be made immediately following the event

as described in ER 1110-2-1802.

(14) Any other indications of distress or

potential failure that could inhibit the operation of a

project or endanger life or property.

(15) Excessive vibration, binding, unusual

noises, movements, or deflections of gate hoist

operatiing equipment.

(16) Actual hydraulic equipment operating

pressure in excess of 125 percent of the normal

operating pressure. Electric motor operating

equipment overheating or stalling.

(17) Erratic movement or unusual sounds, such

as bumping, jumping, or popping of lock miter gates.

(18) Wire rope lifting cables or lifting chains

having broken strands or deformed, worn, or severely

corroded links.

(19) Frequent power interruptions.

(20) Excess movement of penstock flexible

couplings.

(21) Penstocks or turbine spiral cases that show

signs of distress such as deformation or cracking.

(22) Failure of major mechanical or electrical

equipment at local flood protection projects.
EP 1110-2-13

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5-1

Chapter 5

Rehabilitation and Modification of

Dams

5-1. Dam Safety Rehabilitation

Rehabilitation or modification of Corps of Engineers

dams for safety purposes is accomplished through the

Major Rehabilitation Program and the Dam Safety

Assurance Program.

5-2. Major Rehabilitation Program

The Major Rehabilitation Program is to allow

accomplishment of significant, costly, one-time structural

rehabilitation or major replacement work (other repairs

related to dam safety are accomplished under the normal

Operation and Maintenance program). The work under

this program restores the project to its original condition

to serve as originally intended. An example of dam

safety work under this program would be the installation

of a "cut-off" wall to control seepage through a dam.

Projects approved for major rehabilitation require budget

justification and other supporting data similar to the

budget information prepared for construction projects.

The Major Rehabilitation Program is limited to the major

repair or restoration of main structures such as dams,

locks, and powerhouses, exclusive of electrical, mechanical, and other equipment, except that such equipment

may be included where it is essential to and integral with

the feature of the project being rehabilitated. The Major

Rehabilitation Program is not applicable to local protection projects, dams, or other works turned over to local

interests for operation, maintenance, and major replacement (U.S. Army Corps of Engineers, Office of the Chief

of Engineers 1977; ER 1130-2-500; Federal Emergency

Management Agency 1992b; Wiseman 1987).

5-3. Dam Safety Assurance Program

a. General. The Dam Safety Assurance Program

provides for modification of completed Corps of

Engineers dam projects which are potential safety

hazards in light of current engineering standards and

criteria. This program is one part of the Corps'

numerous dam safety activities. The problems

generally fall into two categories: hydrologic and

seismic. The program is intended to facilitate

upgrading of those project features which have design

or construction deficiencies related to dam safety in

order to permit the project to function effectively and

as originally intended. In order to qualify, the

modifications must be within the Chief of Engineers'

discretionary authority and also must be such that they

cannot be accomplished under routine maintenance.

Projects approved for Dam Safety Assurance will

require budget justification and other supporting data

similar to the budget information prepared for

construction projects. The Dam Safety Assurance

Program may also be used to modify dams built by the

Corps of Engineers and turned over to local interests

to operate, maintain, replace, rehabilitate, and repair

(ER 1130-2-419, ER 1165-2-119, ER 1110-2-1155,

Walz 1990a).

b. Policy on hydrologic criteria. Since the

Corps of Engineers began building dams, the policy

has been that failure of a Corps of Engineers dam

should not significantly increase the downstream

hazard over the hazard which would have existed if

the dam had not failed. However, new policy requires

more analysis and documentation from the field

offices when recommending improvements to

hydrologically deficient dams (Duscha 1986).

Additional background information on hydrologic

criteria is available (National Research Council 1985;

Federal Emergency Management Agency 1986a,

1986c; Wiseman 1987; Lave, Resendiz-Carrillo, and

McMichael 1990; Task Committee on Spillway

Design Flood Selection, Committee on Surface Water

Hydrology, Hydraulics Division, American Society of

Civil Engineers 1988). The following policy is used

to make decisions on the merits of dam safety

modifications to meet current hydrologic criteria given

in ER 1110-8-2(FR) (ER 1110-2-1155).

(1) Planning for a dam safety modification will

consider combination of structural design

modifications as well as nonstructural measures,

including downstream actions and changes in water

control plans. The recommended plan should be for

the dam safety modification which meets or exceeds

the base safety condition (BSC). The BSC will be met

when a dam failure related to hydrologic capacity will

result in no significant increase in downstream hazard
EP 1110-2-13

28 Jun 96

5-2

(loss of life and economic damages) over the hazard

which would have existed if the dam had not failed.

Recommendations for any modifications that would

accommodate floods larger than the flood identified as

the BSC must be supported by an analysis that presents

the incremental costs and benefits of the enhanced design

in a manner that demonstrates the merits of the

recommendation. Such enlargement of project scope

may require Congressional authorization. 

(2) Determination of the flood that identifies the

BSC will require definition of the relationship between

flood flows and adverse impacts (loss of life and

economic damages) with and without dam failure for a

range of floods that fully utilizes the existing structure up

to the probable maximum flood (PMF). Selection of a

BSC predicated on the hazard to life from dam failure

will require supporting information to demonstrate that

the safety of the population would actually be threatened.

The evaluation should distinguish between total

population downstream of a dam and the population that

would likely be in a life threatening situation given the

extent of prefailure flooding, warning time available,

evacuation opportunities, and other factors that might

affect the occupancy of the incrementally inundated area

at the time the failure occurs. Appropriate freeboard

necessary to accommodate potential wind and wave

conditions will be included for all flood evaluations. The

evaluation consists of two phases. Phase I is a

comparative hazard analysis in which the threshold flood

and the BSC are established. Phase II is the risk-cost

analysis required if modifications for a flood larger than

the BSC is recommended (ER 1110-2-1155). Examples

of the analysis required to develop the base condition are

illustrated in "Guidelines for Evaluating Modifications of

Existing Dams Related to Hydrologic Deficiencies,"

Institute for Water Resources Report 86-R-7 (Stakhiv

and Moser 1986).

(3) Selection of a recommended level of

modification also should reflect concern for economy.

Modification costs in the vicinity of the scale of

improvement identified as the BSC should be examined

for sudden increases in the cost/scale of improvement

relationship. This type of change could occur, for

instance, when a costly highway relocation is

encountered near the scale of improvement identified as

the BSC. An adjustment in the level of fix recommended

may be warranted under these conditions. On the other

hand, the large increase in costs may be justified if a

significant reduction in the hazard, with and without

dam failure, is achieved. 

(4) Measures to accommodate floods larger

than the BSC may be warranted in some cases. When

the project benefits that would be lost, and repair costs

for failure are large enough, costs for structural

modifications to prevent failure may be economically

justified in spite of the low probability of the floods

involved. 

(5) Conduct of the analysis requires careful

application of professional judgment for determining

those parameters where data and modeling capability

are limited. Therefore, the importance of documenting

the logic assumptions, critical to the conclusions and

recommendations drawn from the analysis, cannot be

over-emphasized. Also, the evaluation should

produce a significant amount of information needed

throughout the decision making process, particularly

in those cases where it is appropriate to proceed

beyond the base condition. The information must be

displayed in a format that assists the decision maker

when evaluating the important trade-offs involved. 

c. Policy on seismic criteria. The following

policy is used to make decisions on the merits of dam

safety modifications related to current earthquake

design criteria (ER 1110-2-1155).

(1) Projects that retain or have the potential to

retain a permanent pool, failure of which would result

in loss of life, substantial property damage, or indirect

loss such as the loss of essential emergency services

provided by the dam, are required to survive and

remain safe during and following the maximum

credible earthquake event. Such projects shall

additionally be capable of remaining operational with

only minor repair during and after an operating basis

earthquake (OBE). In the case of projects intended for

short-term temporary flood storage, including those

with low permanent pools, risk based assessments may

be warranted. Combining a rare earthquake event

with a rare hydrologic event demonstrates extremely

low risk and therefore unwise use of funds.

(2) Technical requirements for selecting

seismic design values and performing design analyses

are contained in ER 1110-2-1806 (see also Federal 
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28 Jun 96

5-3

Emergency Management Agency 1985b). These criteria, along with current state-of-the-art techniques, are

intended to be used in such studies and analyses.

Criteria levels, safety factors, and design methods are

the same as that for new projects.

(3) Since judgment of ground motion

parameters for design is based on geologic and seismic

history, future strong seismic events may raise the

design values against which stability should be

analyzed. Should such a situation occur, the district,

if convinced that the ground motion parameters have

changed significantly enough to affect the safety of the

project, shall prepare an evaluation report as detailed

in paragraph 5-4.a. 

(4) Strong motion accelerometers that have

been placed on or around Corps dams are intended as

a check on the design seismic resistance of the

structure. If these instruments record ground motion

parameters that, after analysis, are found to be below

the values used in design but yet the structure received

damage, a letter report (in the case of no expected

future remedial action) or an evaluation report (in the

case of anticipated remedial action) shall be written

describing the situation and containing the district's

recommendation. 

(5) Seismic stability of auxiliary structures and

devices, such as regulating outlet towers, spillway

gates, retaining walls, hydraulic equipment, and

electric lines, shall be upgraded where necessary to

provide for dam safety, including requirements for

dams to remain operational following the OBE.

Auxiliary structures that do not affect dam safety or

operational safety shall be judged for modification on

economic or other grounds rather than dam safety. 

(6) Seismic stability assessment for dam safety

may also involve reservoir rim slides, effects of dam

overtopping, movements of critical retaining walls,

foundation or abutment changes, susceptibility of

embankment dams to liquefaction, or any other feature

that might contribute to dam failure. 

5-4. Procedural Requirements

In order to identify and process work for inclusion in

the Dam Safety Assurance Program, reporting and
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5-4

design procedures given in ER 1110-2-1155 will be

followed.

a. Dam Safety Assurance Evaluation Report. A

reconnaissance will be conducted and a report prepared

covering preliminary evaluation of work items

considered necessary to upgrade the project. Format and

content of the evaluation report will follow the

requirements given in Appendix C of ER 1110-2-1155.

Detailed field investigations and office studies will be

kept to a minimum. The report will be designed to

develop a basis for decision on:

(1) The need for and justification of the

modification for dam safety.

(2) The appropriateness of funding under the

Dam Safety Assurance Program.

(3) Whether the work requires additional

authorization.

(4) Whether the work is subject to cost-sharing

and identification and the views of the cost sharing

partner.

(5) The scope and cost of subsequent

investigations.

(6) The scope and cost of design requirements.

(7) The estimated cost for construction.

If a determination on whether a problem exists cannot

be made during the preparation of the evaluation

report, then the need for special engineering

investigation(s) will be identified and justified in the

report. In those instances where there is need for both

a special engineering investigation and follow-on

investigations of known problems, both will be

identified in the report. In addition, a plan of study

and cost estimate for the special engineering investigation(s) will be included. Special engineering

investigations are those extensive and complex

investigations that may be required to determine

the need for and/or scope of remedial construction.

Special investigations include hydraulic modeling and

geological and seismic investigations. 

b. Design memorandum. For major dam

safety modifications, a DM is usually prepared

following approval of the evaluation report and any

special investigations. Content of the DM will follow

the requirements given in Appendix D of ER 1110-2-

1155. The initial DM will present the results of the

evaluation report and any special engineering

investigations and make final recommendations

concerning the need for and/or scope of the proposed

modification. Included with this recommendation will

be the estimated cost, schedule for construction, and

design of the approved plan. This will provide the

basis for preparation of plans and specifications.
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6-1

Chapter 6

Emergency Action Plans (EAP)

6-1. General

a. Definitions.

(1) Emergency - An emergency, in terms of

dam operation, is defined as a condition which

develops unexpectedly, endangers the structural

integrity of the dam and/or downstream property and

human life, and requires immediate action.

(2) EAP - An EAP is a plan of action to reduce

the potential for property damage and loss of life in an

area affected or about to be affected by a dam failure or

large flood. It includes both the portion of a dam safety

plan prepared by the Corps of Engineers and the

complementary evacuation plan prepared by nonFederal interests.

b. Background. Corps of Engineers major

subordinate command offices were instructed in March

1978 to begin preparation of flood EAPs for dams

under their jurisdiction. Initially the effort was directed

to delineate areas downstream from the dams that

would be flooded in the event of dam failure. The

product of these efforts was inundation area maps

(ER 1130-2-419). In June 1980 the Corps of

Engineers issued detailed instructions for the

preparation of flood EAPs (U.S. Army Corps of

Engineers, Hydrologic Engineering Center 1980,

1982). Subsequently, in August 1983, the Corps of

Engineers distributed case studies of an EAP and

evacuation plan to field offices (U.S. Army Corps of

Engineers, Hydrologic Engineering Center 1983a,

1983b). 

6-2. Scope of Emergency Action Plan

Guidance (U.S. Army Corps of Engineers, Hydrologic

Engineering Center 1980) has been provided for

preparation of EAPs to deal with potential emergencies

caused by

a. Spillway discharges sufficiently large to

cause flooding in downstream areas.

b. Flooding upstream of dams due to backwater

effects or high pool levels.

c. Dam failure.

6-3. Components of Emergency Action Plan 

The principal components of EAPs (including agency

responsible for preparation) are as follows (U.S. Army

Corps of Engineers, Hydrologic Engineering Center

1980): 

a. Emergency identification subplan (Corps of

Engineers). The object of this subplan is to describe

procedures and means for ensuring reliable

identification and evaluation of existing or potential

emergencies. The major elements of the subplan are: 

(1) Listing of the conditions which could indicate

an existing or potential emergency.

(2) Description of the data and information

collection system, monitoring arrangements, inspection

procedures, and other provisions for early detection of

conditions indicating an existing or potential emergency.

(3) Procedures, aids, instructions, and other

provisions for interpreting information and data to

assess the severity and magnitude of any existing or

potential emergency.

b. Emergency operations and repair subplan

(Corps of Engineers). The objectives of this subplan are

to guide immediate operational decisions in the event of

various types of emergencies; identify the need for

equipment, material, labor, and other necessities for

carrying out emergency repairs; and describe the

procedures for securing and employing needed

equipment, material, labor, and other necessities. The

major elements of the subplan are:

(1) Identification of the appropriate response to

the type and severity of existing or potential

emergencies. 

(2) Emergency gate operation.

(3) Reservoir dewatering plan.
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6-2

(4) Description of equipment and materials to

be stockpiled for use in carrying out emergency

operations and repairs.

(5) Assignments of responsibilities for carrying

out emergency operations and repairs.

(6) Description of needs for equipment,

material, and labor not available at the site which are

needed to carry out each type of emergency operation

or repair. 

(7) Listing of nearby contractors and other

sources of needed equipment, material, and labor and

description of procedures for securing their assistance

on an emergency basis.

c. Notification subplan (Corps of Engineers

and non-Federal). The objective of this subplan is to

describe the procedures and means for prompt

notification of appropriate parties concerning existing

or potential emergencies. The major elements of the

subplan are:

(1) Inundation maps which show the area likely

to be inundated and time of onset of dangerously high

flows for each emergency condition for which plans

are made (Corps of Engineers). 

(2) Listing of vital services and facilities outside

the area of inundation which will or may be disrupted

by the level of inundation associated with each

emergency condition for which plans are made (nonFederal).

(3) Listing of major secondary problems

resulting from the level of inundation associated with

each emergency condition for which plans are made

(non-Federal):

(4) Evacuation maps which show (nonFederal):

(a) All areas which should be evacuated

because of inundation, secondary problems, loss of

services, isolation, or other reasons which are

associated with each emergency condition for which

plans are made.

(b) Major evacuation routes.

(c) Areas requiring priority in evacuation.

(d) Potential obstacles to timely evacuation.

(5) Listing of persons to be notified about each

emergency condition for which plans are made and

procedures for notification including description of

primary and secondary means of communication to be

used, listing of telephone numbers and addresses, and

other information needed for reliable and prompt

contact for (Corps of Engineers):

(a) Notifications internal to the Corps.

(b) Notifications from the Corps to principal

local officials.

(c) Notifications from the Corps to other Federal

officials.

(d) Distribution of warnings from the Corps to

officials responsible for dissemination to the general

public.

(e) Dissemination of warnings by the Corps

directly to the general public in the immediate vicinity of

the dam and reservoir.

(6) Example press releases for each emergency

condition for which a plan is prepared and instructions

for adaptation before their use to the specifics of an

emergency situation including but not limited to (Corps

of Engineers):

(a) Exact nature of emergency and degree of

danger.

(b) Remedial action under way.

(c) Expected course of events and timing.

(d) Appropriate action for public to take.

(7) Description of the procedure and means for

dissemination of warnings directly to the general public

in the immediate vicinity of the dam and reservoir

(Corps of Engineers).
EP 1110-2-13

28 Jun 96

6-3

d. Evacuation subplan (non-Federal). NonFederal officials are to be encouraged to develop

evacuation subplans as a complement to the portion of

dam emergency plans prepared by the Corps. The

objectives of the evacuation subplan are to provide for

the timely and safe evacuation of threatened areas and

the minimization of property damage. The major

elements of the subplan are:

(1) Description of traffic control arrangements

to expedite evacuation and passage of emergency

vehicles and prevent accidental travel into dangerous

areas.

(2) Provisions for any necessary assistance to

evacuees such as transportation and aid to invalids.

(3) Arrangements for sheltering, feeding, and

other care of evacuees.

(4) Description of actions to be taken to reduce

damages and other losses.

(5) Arrangements for security of evacuated

areas.

(6) Arrangements addressing other aspects as

required for the case at hand.

6-4. Number of Emergency Action Plans

Required 

A large number of hypothetical emergencies could be

conceived by combining various causes for and

assumptions about emergencies of one type or another.

It is obviously impractical to prepare completely

separate plans to address each potential emergency

condition which might be postulated. Instead, each

major portion of the emergency plan must be

considered individually with respect to how many

separate versions are necessary (U.S. Army Corps of

Engineers, Hydrologic Engineering Center 1980):

a. Emergency identification subplan (Corps of

Engineers). Only one emergency identification

subplan is required.

 

b. Emergency operations and repair subplan

(Corps of Engineers). The emergency operations and

repair subplan consists of guidance and procedures for

dealing with a variety of emergencies. One subplan is

sufficient. The portion of its contents dealing with

emergency responses should be divided according to the

type of emergency addressed or action to be taken as,

for example, the following:

(1) Wave erosion.

(2) Excess seepage.

(3) Piping.

(4) High pool conditions.

(5) Malfunction of control gates.

(6) Failure of discharge facilities.

(7) Upstream dam failure.

(8) Downstream dam failure.

c. Notification subplan (Corps of Engineers and

non-Federal). Notification subplans are to be prepared

for three basic emergency conditions including:

spillway design discharge without failure, spillway

design discharge with failure, and failure at normal high

pool level (top of flood control pool). Separate

notification subplans are required for each emergency

condition because:

(1) Identification of the local officials to be

notified of an existing or potential emergency depends

on the area requiring evacuation which is associated

with each emergency condition.

(2) The need to notify other Federal agencies, the

public in the immediate vicinity of the dam and

reservoir, and other parties varies according to the

nature of the existing or potential emergency.

(3) The appropriate text of news releases

depends on the emergency condition for which they are

prepared. 
EP 1110-2-13

28 Jun 96

6-4

d. Evacuation subplan (non-Federal).

Evacuation subplans will be prepared for conditions of:

(1) Spillway design flood.

(2) Spillway design flood with dam failure.

(3) Dam failure with normal high pool level

(top of flood control pool).

6-5. Emergency Action Plan Exercises 

a. General. Testing of the EAP involving all

participants is necessary to ensure that the plan is up-todate and workable in practice under real-life conditions

(Basinger 1990, Mahoney 1990, Gotzmer 1991).

b. Corps of Engineers requirements. ER 1130-

2-419 states:

Division Commanders are directed to

implement a dam safety training program

for O&M personnel, with retraining every

four years...Upon completion of initial

safety training sessions for each project,

operational training exercises for emergency situations shall be developed. These

exercises shall be based on the more

probable emergency situations that might

occur on each major dam feature. A record

shall be maintained at the project showing

date, subject material, and personnel

involved for each exercise conducted.

According to the "Emergency Action Planning

Guidelines for Dams" developed by the Interagency

Committee on Dam Safety and adopted by the Corps of

Engineers (Federal Emergency Management Agency

1985, 1990b):

The dam owner should prepare scenarios

for slowly developing, rapidly developing,

and instantaneous emergencies and test the

state of training and readiness of key

personnel responsible for actions during an

emergency to assure that they know and

understand the procedures to be followed 

and actions required. Any special

 procedures required for nighttime, weekends, and holidays should also be included. 

The tests should include a drill simulating 

emergenc condition. Coordination and 

consultation with local government, law 

enforcement officials, and other organizations involved is desirable in order to 

enhance the realism of the test. Their 

involvement will perfect the close 

coordination with agencies necessary 

for a successful execution of the plan in 

an actual emergency. The test should be 

critiqued in writing and the plan should be

 revised to correct any deficiencies noted.

c. Types of exercises. FEMA has identified five

types of exercises that constitute an exercise program,

with each one building on the concepts of the previous

exercise. These five types of exercises are (Federal

Energy Regulatory Commission 1991; Federal

Emergency Management Agency 1989a, 1989b;

Gotzmer 1991):

(1) Orientation seminar. This involves bringing

together persons with a role or interest in the EAP for

discussion and to initiate plans for the annual drill or

more in-depth exercise, and to become familiar with the

roles, procedures, and responsibilities of those involved.

(2) Drill. A drill is the lowest level exercise. A

drill test develops or maintains skills in a single

emergency response procedure. The in-house drill tests

the state of training and readiness of key personnel to

ensure that they are fully cognizant of the procedures

and actions required during an emergency. The drill

should simulate an emergency condition at the dam

under which the EAP would be implemented. Special

procedures required for nighttime, weekends, and

holidays should also be considered when developing the

scenario. Testing of remote sensing instrumentation

should be included. Coordination with local

government, law enforcement officials, and other

organizations involved is desirable. This will enhance

the realism of the drill and ensure the accuracy of

telephone numbers of persons to be notified. While a

planned drill will allow persons involved to rehearse

their roles, a surprise drill can be more educational and

expose flaws in the EAP. Immediately following the 
EP 1110-2-13

28 Jun 96

6-5

drill the responses to the emergency scenario at all

levels will be reviewed and a critique prepared. The

purpose of the critique is to identify lessons learned and

deficiencies in the EAP including notification,

priorities, and responsibilities assigned.

(3) Tabletop exercise. The tabletop exercise

involves low stress, little attention to real-time, lower

level of preparatory effort, and only rough attempts to

simulate actual conditions. The tabletop exercise is

conducted once a year. The focus is on training and

familiarization with roles, procedures, responsibilities,

and personalities of the persons involved. The tabletop

exercise consists of discussion in a meeting format

through one or more facilitators. The facilitator leads

the conduct of the tabletop exercise and makes sure

every participant responds to at least one message

(described below) during the exercise. Effectiveness is

determined by the impact of feedback from the

participants on evaluating and revising policies, plans,

and procedures. There is no deployment of resources

or utilization of equipment. A narrative (or scenario)

sets the scene for the simulated event by briefly

describing what has happened and what is known up to

the time of the exercise. The participants are provided

with messages as the exercise progresses. The purpose

of the messages is to provide updated information to

the participants so that they will respond with an action

or a decision. Once the exercise is completed, the

results will be evaluated. An immediate post-exercise

critique should be held followed by an evaluation

report. The critique will be both oral and written and

will provide the participants with a forum to gather and

share information about what happened during the

exercise, to describe what went right, and to identify

what went wrong. The formal evaluation of the

exercise consists of a written report based on

observations and recommendations that come out of

the critique, as well as the report(s) of the facilitator(s).

Follow-up (the process of implementing the

recommendations) is the final and critical stage of the

exercise process. The advantage of a tabletop exercise

is the modest commitment of time, cost, and resources.

It provides an effective method of reviewing plans and

implementing procedures and policies, and provides an

opportunity for key personnel to become acquainted

and review emergency responsibilities and procedures.

The disadvantages of a tabletop exercise are that the 

tabletop lacks realism and does not provide a true test of

participants' capabilities. 

(4) Functional exercise. The functional exercise

is the highest level test that does not involve full

activation of field personnel and facilities. The

functional exercise is conducted once every 4 years.

The functional exercise tests capabilities of the

participants under a stress-induced environment with

time constraints. Whereas a tabletop exercise provides

opportunities throughout the exercise to stop and discuss

actions and responses, the functional exercise is a time

constrained test with limited opportunity for discussion.

The functional exercise simulates actual emergency

situations and responses of the participants without

actual field deployment. The exercise is conducted with

the participants co-located or located at their own

facilities, with communications through expected

emergency communication links. The functional

exercise is based on a simulation of an emergency

including a description of the situation, a master

sequence of events list, a timed sequence of messages,

and communication between participants and simulators.

There are five functions or capabilities which should be

included in a functional exercise:

(a) Alert, notification, and warning. This

function tests the communication system and the

messages to determine if they are appropriate and

clearly understood. It verifies names and phone

numbers on the notification list. Remote sensing

equipment should be tested at the start of the exercise.

(b) Direction and control function. This function

tests and evaluates the emergency operations capability

and timely response. It includes the response to health

problems, fire, downed power lines, and loss of life, including drownings.

(c) Evacuation. This capability is a key issue in

the exercise as it tests the participants' understanding of

the inundation maps. Experience indicates the

inundation boundaries and the road names may not

always be clear and fully understood (for example, road

names used by local officials are often different from

those on Geological Survey maps or state route maps).

Maps are often revised as a result of this information.
EP 1110-2-13

28 Jun 96

6-6

(d) Shelters. This function reveals those

shelters that should not be used because they are in the

flood plain.

(e) Public information. This function tests the

capability to issue accurate information during a dam

failure event. Activation of the emergency operations

center at the state or local level, as appropriate, should

be encouraged. Apart from the actual participants in

the functional exercise there are the exercise controller,

exercise simulators, and exercise evaluators. The

controller monitors the sequence of events as they

unfold, the flow of messages, and the overall conduct

of the exercise. The simulators send prescribed

messages at the scheduled time, respond to

unanticipated actions by participants with spontaneous

messages, and maintain contact with the controller

during the exercise. The evaluators observe the actions

and decisions of the participants during the exercise

and contribute, along with the exercise participants, to

writing the evaluation report. As with the tabletop

exercise, the critique, the evaluation report, and the

follow-up to the recommendations in the report are

important aspects of the functional exercise.

 

(5) Full-scale exercise. The full-scale exercise

is the most comprehensive test and is intended to

evaluate the operational capability of the emergency

management system in a stress environment with

mobilization of emergency workers, equipment, and

resources to demonstrate coordination and response

capability. Full-scale exercises draw media and

community attention to emergency preparedness; teach

by doing; test total coordination, not only among policy

and coordination officials, but also field forces; and

point out physical resource capabilities and/or

limitations. For agencies or local communities,

full-scale exercises require considerable preparation

and provide practical tests of "first-in" responders,

including police, fire, and medical personnel. They test

triage (allocation of treatment to disaster victims to

maximize the number of survivors) procedures, onscene management of resources, and coordination and

communication through field command posts. As with

the functional exercise, the controller is responsible for

ensuring that the exercise starts on schedule. Simulators

and evaluators keep a log of all significant events.

During a full-scale exercise at Garrison Dam, North

Dakota, conducted in August 1987, personnel were

stationed at several locations in the District Office

and at Garrison Dam to monitor and document phone

and radio communications, decision making, and repair

efforts (U.S. Army Engineer District, Omaha 1987).

Each participant should log his actions as much as

possible. Videotaping the exercise and critique is

beneficial. The media should be included in any

exercise plan to increase realism. At the conclusion of

the full-scale exercise, the critique and evaluation report

are important so that necessary follow-up action can be

taken.
EP 1110-2-13

28 Jun 96

7-1

Chapter 7

Training

7-1. Overview 

The Corps of Engineers has an extensive program for

training its personnel in all matters related to its mission

in water resources development. Much of the training

is directly or indirectly related to dam safety. A

comprehensive training program is conducted for dam

operation and maintenance personnel. This program is

designed to acquaint project personnel with basic

engineering considerations pertaining to the major

structures, with procedures for surveillance, monitoring

and reporting of potential problems, and with

emergency operations. The Corps of Engineers has a

training course on "Design and Safety Surveillance of

Embankment Dams" and supported the development of

the Training Aids for Dam Safety (TADS) Program

(Walz 1990b). In 1991, the Federal Energy Regulatory

Commission initiated a training course on "Emergency

Action Plan" (Gotzmer 1991). A listing of Government

sponsored training courses relating to dam safety was

prepared by the Interagency Committee on Dam Safety

(ICODS) Subcommittee on Training (Federal

Emergency Management Agency 1986b).

7-2. Training Program for Operations and

Maintenance Personnel 

a. Dam safety. Recognizing the important role

which onsite operations and maintenance personnel

have in dam safety, major subordinate command

commanders were directed in 1978 to develop a

training program which addresses the following items

(ER 1130-2-419, United States Committee on Large

Dams 1982):

(1) Discussion of basic typical design

considerations for various types of construction,

including hydraulic considerations and foundation

factors.

(2) Procedures for monitoring potential problem

areas.

(3) Dam safety features in design and

construction.

(4) Normal operation, surveillance, monitoring,

and reporting procedures.

(5) Emergency operations, surveillance,

monitoring, and reporting procedures.

b. Exercises. Upon completion of the initial

safety training at a new project, EAP exercises are

developed based on the most probable emergency

situations that might occur on each major dam feature.

Operations and maintenance personnel are retrained

every 4 years. 

7-3. Corps of Engineers Training Course on

Dam Safety 

The Corps of Engineers Proponent Sponsored Engineer

Corps Training (PROSPECT) program offers a course

titled “Dam Safety in the Corps of Engineers”.

Through lectures, case histories, and structured student

discussions, the course covers all aspects of a dam

safety program. The course outlines technical

considerations (hydrologic, seismic, geotechnical,

electrical/mechanical and structural) as well as the

operational requirements (operation, maintenance,

surveillance, preparedness, training, and notification).

The scope and implementation details of the Dam

Safety Assurance Program are covered in detail.

Presentations, video modules, case histories, and a

walk-through inspection are used to effectively present

a multidiscipline approach to the successful monitoring

and evaluation of Corps of Engineers dams.

7-4. Training Aids for Dam Safety

a. Background. In 1986, the Corps of

Engineers, along with 13 other Federal Agencies, all

members of the Interagency Committee on Dam Safety,

joined forces to develop a professionally prepared

TADS Program. The TADS materials, as shown in

Table 7-1, are arranged in three components that cover

dam safety inspections, dam safety awareness and

program development, and evaluations and remedial 
EP 1110-2-13

28 Jun 96

7-2

actions (Federal Emergency Management Agency

1992b, Veesaert 1990). 

b. Structure. The entire package consists of 21

self-paced individual instruction modules that focus on

performance of job tasks. Each module features a

workbook text. The material is presented in a

straightforward, easy-to-manage manner. Each

workbook contains a glossary of terms and a list of

references from which to obtain additional information.

Nine of the modules are supplemented with videotapes

that illustrate certain concepts. Because the modules are

self-contained, individuals may tailor a learning

program to meet specific work requirements or personal

needs (Federal Emergency Management Agency 1992b,

Veesaert 1990). 

c. Utilization of the program. The TADS

Program promises to offer a standardized approach to

dam safety training. The Corps of Engineers, as one of

the primary sponsors of the TADS Program, distributes

the TADS materials to each Corps of Engineers field

office through the Engineering Division, Directorate of

Civil Works, HQUSACE. All MSCs and districts

should have a complete set of modules including the

videotape supplements.

Table 7-1

Training Aids for Dam Safety Modules 

Safety Inspection of Dams 

(for engineers with little or no inspection experience and 

technicians with some familiarity with dams)

Preparing to Conduct a Dam Safety Inspection

Documenting and Reporting Findings From a 

 Dam Safety Inspection

Inspection of Embankment Dams *

Inspection of Concrete and Masonry Dams *

Inspection of the Foundation, Abutments, and 

 Reservoir Rim

Inspection of Spillways and Outlet Works *

Inspection and Testing of Gates, Valves, and 

 Other Mechanical Systems *

Instrumentation for Embankment and Concrete 

 Dams *

Identification of Material Deficiencies *

Evaluation of Facility Emergency Preparedness

Dam Safety Awareness, Organization, and Implementation

(for dam owners and operators, with some applicability 

for inexperienced engineers, technicians, administrators, 

and the general public)

Dam Safety Awareness * 

How to Organize a Dam Safety Program

How to Organize an Operation and Maintenance 

 Program

How to Develop and Implement an Emergency 

 Action Plan *

Identification of Visual Dam Safety Deficiencies *

Data Review, Investigation and Analysis, and Remedial

Action for Dam Safety (for engineers with some applicability

for dam owners and operators)

The Dam Safety Process

Evaluation of Hydrologic Adequacy

Evaluation of Hydraulic Adequacy

Evaluation of Concrete Dams Stability

Evaluation of Embankment Dams Stability 

 and Deformation

Evaluation of Seepage Conditions

* Modules have videotape supplements.
EP 1110-2-13

28 Jun 96

A-1

Appendix A

References

A-1. Required Publications1

PL 99-662

Water Resources Development Act of 1986

ER 5-7-1(FR) 

Project Management

ER 415-2-100

Construction Management Policies, Procedures, and

Staffing for Civil Works Projects

ER 690-1-304

Employment of Experts and Consultants for Personal

Services

ER 1105-2-100

Guidance for Conducting Civil Works Planning Studies

ER 1110-1-1801

Construction Foundation Report

ER 1110-2-100

Periodic Inspection and Continuing Evaluation of

Completed Civil Works Structures

ER 1110-2-101

Reporting of Evidence of Distress of Civil Works

Structures

ER 1110-2-110

Instrumentation for Safety Evaluations of Civil Works

Projects

ER 1110-2-112

Required Visits to Construction Sites by Design

Personnel

ER 1110-2-1150 

Engineering and Design for Civil Works Projects

_____________________________

 References published by the Department of the 1

Army and are available through USACE Command

Information Management Office Sources.

ER 1110-2-1155

Dam Safety Assurance Program

ER 1110-2-1156

Dam Safety - Organization, Responsibilities, and

Activities

ER 1110-2-1200

Plans and Specifications for Civil Works Projects

ER 1110-2-1802

Reporting Earthquake Effects

ER 1110-2-1806

Earthquake Design and Evaluation for Civil Works

Projects

ER 1110-2-1901

Embankment Criteria and Performance Report

ER 1110-2-1925

Field Control Data for Earth and Rockfill Dams

ER 1110-8-2(FR)

Inflow Design Floods for Dams and Reservoirs

ER 1130-2-304

Manuals

ER 1130-2-417

Major Rehabilitation Program and Dam Safety

Assurance Program

ER 1130-2-419

Dam Operations Management Policy

ER 1165-2-119 

Modifications to Completed Projects

ER 1165-2-131

Local Cooperation Agreements for New Start Construction Projects

ER 1180-1-6

Construction Quality Management

EP 715-1-2

A Guide to Effective Contractor Quality Control (CQC)
EP 1110-2-13

28 Jun 96

A-2

EM 1110-2-1908

Instrumentation of Earth and Rock-fill Dams - Parts 1

and 2

EM 1110-2-1911 

Construction Control for Earth and Rock-fill Dams

EM 1110-2-2006

Roller-Compacted Concrete

EM 1110-2-2200

Gravity Dam Design

EM 1110-2-2300

Earth and Rock-Fill Dams - General Design and Construction Considerations

EM 1110-2-3600

Management of Water Control Systems

EM 1110-2-4300

Instrumentation for Concrete Structures

A-2. Related Publications 2

Association of State Dam Safety Officials 1989

Association of State Dam Safety Officials. 1989 (Mar).

"Bibliography on Dam Safety Practice," Lexington,

KY.

Basinger 1990

Basinger, D. L. 1990 (Feb). "Have You Reviewed

Your Emergency Action Plan Lately?," Hydro Review,

Vol 9, No. 1, pp 22-28.

Bartholomew, Murray, and Goins 1987

Bartholomew, C. L., Murray, B. C., and Goins, D. L.

1987 (Jan). Embankment Dam Instrumentation

Manual, U.S. Department of the Interior, Bureau of

Reclamation, Denver, CO.

_____________________________

 References available on interlibrary loan from the 2

Research Library, U.S. Army Engineer Waterways

Experiment Station, ATTN: CEWES-IM-MI-R, 3909

Halls Ferry Road, Vicksburg, MS 39180-6199.

Cochrane, Ferrell-Dillard, and Baumann 1987

Cochrane, H. C., Ferrell-Dillard, R., and Baumann, D.

D. 1987 (Jun). "Socioeconomic Considerations in

Dam Safety Risk Analysis," IWR Report 87-R-7,

Institute for Water Resources, Fort Belvoir, VA.

Carpenter et al. 1988

Carpenter, L. R., Lytle, J. D., Misterek, D. L., Murrdy,

B. C., and Raphael, J. M. 1988. "Instrumentation,"

Jansen, R. B., ed., Advanced Dam Engineering for

Design, Construction, and Rehabilitation, Van

Nostrand Reinhold, New York, pp 751-776.

Colorado Division of Disaster Emergency Services

1987

Colorado Division of Disaster Emergency Services.

1987 (Aug). "Dam Safety: An Owner's Guidance

Manual," FEMA 145, Federal Emergency Management

Agency, Washington, DC

Currier and Fenn 1986

Currier, B. and Fenn, M. H. 1986 (Dec). "Available

Data Collection and Reduction Software,"

Instrumentation Automation for Concrete Structures,

Technical Report REMR-CS-5, Report 3, U.S. Army

Engineer Waterways Experiment Station, Vicksburg,

MS.

Duscha 1982

Duscha, L. A. 1982 (Apr). "U.S. Army Corps of Engineers Programs for Safety of Dams in the United

States," United States Committee on Large Dams, Dam

Safety Practices and Concerns in the United States,

Denver, CO, pp 25-54.

Duscha 1984

Duscha, L. A. 1984. "Dam Safety in the United States:

What has been Gained?," Serafim, J. L., ed., Safety of

Dams, A. A. Balkema, Boston, MA, pp 259-263. 

Duscha 1986

Duscha, L. A. 1986 (Oct). "Dam Safety - Past, Recent,

and Future," Current Developments in Dam Safety

Management, FEMA 115, Proceedings of Workshop

held at Stanford University July 24-26, 1985, Federal

Emergency Management Agency, Washington, DC,

pp 1-7 to 1-19. 
EP 1110-2-13

28 Jun 96

A-3

Duscha 1990

Duscha, L. A. 1990. "Dam Safety in Developed

Nations," Le Moigne, G. J.-M., Barghouti, S., and

Plusquellec, H., eds., Dam Safety and the Environment,

World Bank Technical Paper Number 115, Washington,

DC, pp 45-52.

Duscha and Jansen 1988

Duscha, L. A. and Jansen, R. B. 1988. "Surveillance,"

Jansen, R. B., ed., Advanced Dam Engineering for

Design, Construction, and Rehabilitation, Van

Nostrand Reinhold, New York, pp 777-797.

Federal Coordinating Council for Science,

Engineering and Technology 1978

Federal Coordinating Council for Science, Engineering

and Technology. 1978 (Jul). "Improving Federal Dam

Safety," Washington, DC.

Federal Emergency Management Agency 1979

Federal Emergency Management Agency. 1979 (Jul).

"Federal Guidelines for Dam Safety," FEMA 93, (Prepared by the Ad Hoc Interagency Committee on Dam

Safety of the Federal Coordinating Council for Science,

Engineering, and Technology), Washington, DC. 

Federal Emergency Management Agency 1982

Federal Emergency Management Agency. 1982 (May).

"Dam Safety Research, Current, Planned and Future,"

FEMA 21, Washington, DC. 

Federal Emergency Management Agency 1985a*

Federal Emergency Management Agency. 1985 (Feb).

"Emergency Action Planning Guidelines for Dams,"

FEMA 64, Washington, DC. 

Federal Emergency Management Agency 1985b*

Federal Emergency Management Agency. 1985 (Mar).

"Federal Guidelines for Earthquake Analyses and

Design of Dams," FEMA 65, Washington, DC. 

Federal Emergency Management Agency 1986a*

Federal Emergency Management Agency. 1986 (Jan).

"Federal Guidelines for Selecting and Accommodating

Inflow Design Floods for Dams," FEMA 94,

Washington, DC. 

Federal Emergency Management Agency 1986b

Federal Emergency Management Agency. 1986 (Jan).

"Training Courses Related to Dam Safety," FEMA 92,

Washington, DC. 

Federal Emergency Management Agency 1986c

Federal Emergency Management Agency. 1986 (Oct).

Proceedings of the Workshop on Current Developments

in Dam Safety Management, FEMA 115, Washington,

DC. 

Federal Emergency Management Agency 1988a

Federal Emergency Management Agency. 1988 (Feb).

"Glossary of Terms for Dam Safety," FEMA 148,

Washington, DC. 

Federal Emergency Management Agency 1988b

Federal Emergency Management Agency. 1988.

"National Dam Safety Program - 1986 and 1987, A

Progress Report," Washington, DC. 

Federal Emergency Management Agency 1989a

Federal Emergency Management Agency. 1989 (Jan).

"Exercise Design Course - Guide to Emergency

Management Exercises," SM 170.2, Washington, DC.

Federal Emergency Management Agency 1989b

Federal Emergency Management Agency. 1989 (Jan).

"Exercise Design Course - Student Workbook," SM

170.1, Washington, DC.

Federal Energy Regulatory Commission 1991

Federal Energy Regulatory Commission. 1991 (Apr).

"Engineering Guidelines for the Evaluation of Hydropower Projects," FERC 0119-2, Washington, DC.

Federal Emergency Management Agency 1992a

Federal Emergency Management Agency. 1992 (Sep).

"National Dam Safety Program, 1990 & 1991 A

Progress Report," FEMA 235, Vol 1, Washington, DC.

_____________________________

* Adopted by the Corps.
EP 1110-2-13

28 Jun 96

A-4

Federal Emergency Management Agency 1992b

Federal Emergency Management Agency. 1992 (Sep).

"National Dam Safety Program, 1990 & 1991 A

Progress Report," FEMA 236, Vol 2, Washington, DC.

Gotzmer 1991

Gotzmer, J. W. 1991 (Sep). "Emergency Action Plans:

The Comprehensive Exercise," Proceedings of the

Eight Conference of the Association of State Dam Safety

Officials, pp 216-224. 

Government Accounting Office 1977

Government Accounting Office. 1977 (Jun). "Actions

Needed to Increase the Safety of Dams Built by the

Bureau of Reclamation and the Corps of Engineers,"

CED-77-85, Washington, DC. 

Government Accounting Office 1978

Government Accounting Office. 1978 (Jan).

"Improving the Safety of Our Nation's Dams - Progress

and Issues," Report to the Congress, CED-79-30,

Washington, DC.

Haimes et al. 1988

Haimes, Y. Y. Tetrakian, R., Karlsson, P. O., and

Mitsiopoulos, J. 1988 (Apr). "Multiobjective RiskPartitioning: An Application to Dam Safety Risk

Analysis," IWR Report 88-R-4, Institute for Water

Resources, Fort Belvoir, VA.

Hansen and Reinhardt 1991

Hansen, K. D. and Reinhardt, W. G. 1991. RollerCompacted Concrete Dams, McGraw-Hill, Inc, New

York.

Interagency Committee on Dam Safety Research

Subcommittee 1982

Interagency Committee on Dam Safety Research

Subcommittee. 1982 (Oct). Proceedings of the Dam

Safety Research Coordination Conference, Denver, CO.

International Commission on Large Dams 1982

International Commission on Large Dams. 1982. "A

Glossary of Words and Phrases Related to Dams,"

Bulletin 31, Paris, France.

International Commission on Large Dams 1986

International Commission on Large Dams. 1986.

"Quality Control for Fill Dams," Bulletin 56, Paris,

France.

International Commission on Large Dams 1987

International Commission on Large Dams. 1987.

"Dam Safety Guidelines," Bulletin 59, Paris, France.

James 1990

James, R. 1990 (May). "Safety of Dams as Related to

Design and Construction," Design and Safety

Surveillance of Embankment Dams, U.S. Army

Engineer Waterways Experiment Station, Vicksburg,

MS.

Jansen 1983

Jansen, R. B. 1983. Dams and Public Safety,

U.S. Department of the Interior, Bureau of Reclamation,

Denver, CO.

Jansen 1988a

Jansen, R. B. 1988. "Dam Safety Engineering,"

Kollgaard, E. B. and Chadwick, W. L., eds.

Development of Dam Engineering in the United States,

Pergamon Press, New York, pp 1031-1049.

Jansen 1988b

Jansen, R. B. 1988 (Jun). "Dam Safety in America,"

Hydro Review, Vol 7, No. 3, pp 10-20.

Karadi and Landis, eds. 1986

Karadi, G., and Landis, F., eds. 1986 (Jan).

Proceedings of the Workshop on Dam Safety Research

and Development Needs, Denver, CO.

Keeter et al. 1986

Keeter, A., Stonecypher, B., Payne, T., Skeri, M.,

Burton, J., and Jennings, J. 1986 (Dec). "Automation

Hardware and Retrofitting Techniques,"

Instrumentation Automation for Concrete Structures,

Technical Report No. REMR-CS-5, Report 2,

U.S. Army Engineer Waterways Experiment Station,

Vicksburg, MS.
EP 1110-2-13

28 Jun 96

A-5

Kelly 1987 

Kelly, M. T. 1987 (Sep). "Dam Safety Exercise:

Simulated Failure at Fort Peck, Montana," Proceedings

of the Fourth Conference of the Association of State

Dam Safety Officials, pp 20-24. 

Lave, Resendiz-Carrillo, and McMichael 1990

Lave, L. B., Resendiz-Carrillo, D., and McMichael, F.

C. 1990 (Jul). "Safety Goals for High-Hazard Dams:

Are Dams Too Safe?," Water Resources Research,

Vol 26, No. 7, pp 1383-1391. 

Lindsey et al. 1986

Lindsey, J., Edwards, D., Keeter, A., Payne, T.,

Malloy, R. 1986 (Dec). "Instrumentation Automation

Techniques," Instrumentation Automation for Concrete

Structures, Technical Report No. REMR-CS-5,

Report 1, U.S. Army Engineer Waterways Experiment

Station, Vicksburg, MS. 

Mahoney 1990

Mahoney, D. J. 1990 (Jun). "FERC's Dam Safety Program: A New Focus on Monitoring," Hydro Review,

Vol 9, No. 3, pp 38-45. 

Morrison-Knudsen Engineers, Inc. 1986 

Morrison-Knudsen Engineers, Inc. 1986 (Sep).

"Inspection and Performance Evaluation of Dams,"

EPRI AP-4714, Electric Power Research Institute, Palo

Alto, CA.

National Research Council 1983

National Research Council. 1983. Safety of Existing

Dams, Evaluation and Improvement, National

Academy Press, Washington, DC.

National Research Council 1985

National Research Council. 1985. Safety of Dams,

Flood and Earthquake Criteria, National Academy

Press, Washington, DC.

O'Neil 1989

O'Neil, E. F. 1989 (Apr). "Demonstration of

Instrumentation Automation Techniques at Beaver

Dam, Eureka Springs, Arkansas," Instrumentation

Automation for Concrete Structures, Technical Report

No. REMR-CS-5, Report 4, U.S. Army Engineer

Waterways Experiment Station, Vicksburg, MS.

Reed 1987

Reed, J. A. 1987 (Nov). "Suggested Procedures for

Safety Inspections of Dams," Ohio Department of

Natural Resources, Columbus, OH.

Schurer et al. 1988

Schurer, J., Wilkinson, E., Norfleet, J., Sciver, J. V.,

Huntington, C., Lee, C., and Rogers, A. 1988 (Jan).

"Dam Safety Manual," Denver, CO.

Stakhiv and Moser 1986

Stakhiv, E., and Moser, D. 1986 (Oct). "Guidelines for

Evaluating Modifications of Existing Dams Related to

Hydrologic Deficiencies," Institute for Water

Resources, Report 86-R-7, Fort Belvoir, VA.

Tschantz 1982

Tschantz, B. A. 1982 (Apr). "Recent United States

Progress to Improve Dam Safety," United States

Committee on Large Dams, Dam Safety Practices and

Concerns in the United States, Denver, CO, pp 1-24.

Task Committee on Spillway Design Flood Selection,

Committee on Surface Water Hydrology,

Hydraulics Division, American Society of Civil

Engineers 1988

Task Committee on Spillway Design Flood Selection,

Committee on Surface Water Hydrology, Hydraulics

Division, American Society of Civil Engineers. 1988.

"Evaluation Procedures for Hydrologic Safety of

Dams," New York.

Thomas 1987

Thomas, H. E. 1987 (Feb). "Dam Safety: Meeting the

Challenge," Hydro Review, Vol 6, No. 1, pp 38-45.

U.S. Army Corps of Engineers 1987

U.S. Army Corps of Engineers. 1987 (Aug). "Methods

of Automating the Collection of Instrumentation Data,"

REMR Technical Note CS-ES-2.3, U.S. Army Engineer

Waterways Experiment Station, Vicksburg, MS.

U.S. Army Corps of Engineers 1990

U.S. Army Corps of Engineers. 1990 (Mar). "An

Overview of the Repair, Evaluation, Maintenance, and

Rehabilitation (REMR) Research Program 1984-1989,"

Washington, DC.
EP 1110-2-13

28 Jun 96

A-6

U.S. Army Corps of Engineers, Hydrologic

Engineering Center 1980

U.S. Army Corps of Engineers, Hydrologic

Engineering Center. 1980 (Jun). "Flood Emergency

Plans Guidelines for Corps Dams," Research Document

No. 13, Davis, CA.

U.S. Army Corps of Engineers, Hydrologic

Engineering Center 1982

U.S. Army Corps of Engineers, Hydrologic

Engineering Center. 1982 (Jan). "Emergency Planning

for Dams, Bibliography and Abstracts of Selected

Publications," Davis, CA.

 

U.S. Army Corps of Engineers, Hydrologic

Engineering Center 1983a

U.S. Army Corps of Engineers, Hydrologic

Engineering Center. 1983a (Aug). "Example

Emergency Plan for Blue Marsh Dam and Lake,"

Research Document No. 19, Davis, CA.

U.S. Army Corps of Engineers, Hydrologic

Engineering Center 1983b

U.S. Army Corps of Engineers, Hydrologic

Engineering Center. 1983b (Aug). "Example Plan for

Evacuation of Reading, Pennsylvania, in the Event of

Emergencies at Blue Marsh Dam and Lake," Research

Document No. 20, Davis, CA.

U.S. Army Corps of Engineers, Office of the Chief of

Engineers 1977

U.S. Army Corps of Engineers, Office of the Chief of

Engineers. 1977 (Sep). "Report to the Federal Coordinating Council for Science, Engineering, and

Technology on the Dam Safety Program in the Corps of

Engineers," Washington, DC.

U.S. Army Engineer District, Omaha 1987

U.S. Army Engineer District, Omaha. 1987 (Aug).

"Garrison Dam Safety Training Exercise, Lake

Sakakawea, Missouri River, North Dakota," Omaha,

NE.

U.S. Army Engineer District, Vicksburg 1977

U.S. Army Engineer District, Vicksburg. 1977.

"Grenada Lake, Operation and Maintenance Manual,"

Vicksburg, MS.

United States Committee on Large Dams 1982

United States Committee on Large Dams. 1982 (Apr).

"Dam Safety Practices and Concerns in the United

States," Denver, CO.

United States Committee on Large Dams 1984

United States Committee on Large Dams. 1984 (Jan).

"Dam Safety and Rehabilitation," Proceedings of the

Fourth USCOLD Lecture, Denver, CO.

United States Committee on Large Dams 1986

United States Committee on Large Dams. 1986 (Dec).

"General Considerations Applicable to Performance

Monitoring of Dams," Denver, CO.

Veesaert 1990

Veesaert, C. J. 1990 (Jun). "Standardizing the

Approach to Dam Safety Training," Hydro Review,

Vol 9, No. 3, pp 46-50.

Von Thun 1984

Von Thun, J. L.. 1984. "Applications of Decision

Analysis Techniques in Dam Safety Evaluation and

Modification," Serafim, J. L., ed., Safety of Dams, A. A.

Balkema, Boston, MA, pp 265-271.

Walz 1990a

Walz, A. H. 1990 (May). "History of Dam Safety,"

Design and Safety Surveillance of Embankment Dams,

U.S. Army Engineer Waterways Experiment Station,

Vicksburg, MS. 

Walz 1990b

Walz, A. H. 1990 (May). "Special Inspections,

Automation, TADS Program," Design and Safety

Surveillance of Embankment Dams, U.S. Army

Engineer Waterways Experiment Station, Vicksburg,

MS. 

Wiseman 1987

Wiseman, R. 1987 (Sep). "Many U.S. Dams `Still

Unsafe'," World Water, Vol 10, No. 8, pp 17-21.
EP 1110-2-13

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B-1

Appendix B

Glossary

B-1. Abbreviations

ADAS .... Automated Data Acquisition System

ASDSO . . Association of State Dam Safety

 Officials

BSC . . . . . Base Safety Condition

CAGE .... Computer Applications in 

 Geotechnical Engineering

COE . . . . . Corps of Engineers

CQC . . . . . Contractor Quality Control

DA . . . . . . Department of the Army

DM . . . . . . Design Memorandum

EAP . . . . . Emergency Action Plan

EPRI ..... Electric Power Research Institute

FCCSET . . Federal Coordinating Council for

 Science, Engineering, and 

 Technology

FCSA .... Feasibility Cost Sharing

 Agreement

FEMA .... Federal Emergency Management

 Agency

GDM . . . . General Design Memorandum

HQUSACE . . Headquarters, U. S. Army Corp 

 of Engineers

ICODS . . . Interagency Committee on Dam

 Safety

ICOLD . . . International Commission on

 Large Dams

IDF ..... Inflow Design Flood

IPMP .... Initial Project Management Plan

IRC . . . . . . . . . . . . Issue Resolution Conference

MCE . . . . . . . . . . . Maximum Credible Earthquake

MDE . . . . . . . . . . . Maximum Design Earthquake

MSC . . . . . . . . . . . Major Subordinate Commands

O&M . . . . . . . . . . Operation and Maintenance

OBE . . . . . . . . . . . Operating Basis Earthquake

OMRR&R ...... Operation, Maintenance, Repair, 

 Replacement and Rehabilitation

P&S . . . . . . . . . . . Plans and Specifications

PCA . . . . . . . . . . . Project Cooperation Agreement

PED . . . . . . . . . . . Preconstruction Engineering and

 Design

PMF . . . . . . . . . . . Probable Maximum Flood

PMP . . . . . . . . . . . Probable Maximum Precipitation

PROSPECT ..... Proponent-Sponsored Engineer

 Corps Training

QA . . . . . . . . . . . . Quality Assurance

REMR .......... Repair, Evaluation,

 Maintenance, and Rehabilitation

SDF . . . . . . . . . . . Spillway Design Flood

SEE . . . . . . . . . . . . Safety Evaluation Earthquake

SEF . . . . . . . . . . . . Safety Evaluation Flood

TADS .......... Training Aids for Dam Safety

TRC . . . . . . . . . . . Technical Review Conference

USACE ......... United States Army Corps of

 Engineers

USCOLD ....... U.S. Committee on Large Dams

VE . . . . . . . . . . . . . Value Engineering

WES . . . . . . . . . . . U.S. Army Engineer Waterways

 Experiment Station
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B-2

B-2. Terms

Abutment

That part of the valley side against which the dam is

constructed. An artificial abutment is sometimes constructed as a concrete gravity section to take the thrust

of an arch dam where there is no suitable natural

abutment. The left and right abutments of dams are

defined with the observer viewing the dam looking in

the downstream direction, unless otherwise indicated.

Acre-foot

A unit of volumetric measure that would cover 1 acre

to a depth of 1 foot. It is equal to 43,560 cubic feet.

Adit

A nearly horizontal underground excavation in an

abutment having an opening in only one end. An

opening in the face of a dam for access to galleries or

operating chambers.

Appurtenant structure

Ancillary features of a dam such as inlet and outlet

works, spillways, tunnels, or powerplants.

Axis of dam

The vertical plane or curved surface, chosen by a

designer, appearing as a line, in plan, or in

cross-section, to which the horizontal dimensions of

the dam are referenced.

Baffle block

A block, usually of concrete, constructed in a channel

or stilling basin to dissipate the energy of water

flowing at high velocity.

Base thickness

Also referred to as base width. The maximum

thickness or width of the dam measured horizontally

between upstream and downstream faces and normal

to the axis of the dam, but excluding projections for

outlets, or other appurtenant structures.

Batter

Angle of inclination from the vertical.

Bedrock

The consolidated body of natural solid mineral matter

which underlies the overburden soils.

Berm

A nearly horizontal step in the sloping profile of an

embankment dam. Also a step in a rock or earth cut.

Borrow area

The area from which material for an embankment is

excavated.

Breach

An eroded opening through a dam which drains the

reservoir. A controlled breach is a constructed

opening. An uncontrolled breach is an unintentional

opening which allows uncontrolled discharge from

the reservoir.

Catastrophe

A sudden and great disaster causing misfortune,

destruction, or irreplaceable loss extensive enough to

cripple activities in an area.

Channel

A general term for any natural or artificial facility for

conveying water.

Cofferdam

A temporary structure enclosing all or part of the construction area so that construction can proceed in the

dry. A diversion cofferdam diverts a river into a pipe,

channel, or tunnel.

Compaction

Mechanical action which increases the density by

reducing the voids in a material. 

Conduit

A closed channel to convey water through, around, or

under a dam.

Construction joint

The interface between two successive placings or

pours of concrete where bond, and not permanent

separation, is intended.
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B-3

Contact grouting Filling, with cement grout, any voids existing at the

contact of two zones of different materials, e.g.,

between a concrete tunnel lining and the surrounding

rock.

Contractor Quality Control (CQC)

The construction contractor's system to manage,

control, and document his own, his supplier's, and his

subcontractor's activities to comply with contract

requirements.

Core

A zone of low permeability material in an

embankment dam. The core is sometimes referred to

as central core, inclined core, puddle clay core, rolled

clay core, or impervious zone.

Core wall

A wall built of relatively impervious material, usually

of concrete or asphaltic concrete, in the body of an

embankment dam to prevent seepage.

Crest of dam

See top of dam.

Cross section

An elevation view of a dam formed by passing a

plane through the dam perpendicular to the axis.

Cutoff trench

A foundation excavation later to be filled with

impervious material so as to limit seepage beneath a

dam.

Cutoff wall

A wall of impervious material usually of concrete,

asphaltic concrete, or steel sheet piling constructed in

the foundation and abutments to reduce seepage

beneath and adjacent to the dam.

Dam

A barrier constructed across a watercourse for the

purpose of storage, control, or diversion of water.

a. Afterbay dam. See regulating dam.

b. Ambursen dam. A buttress dam in which

the upstream part is a relatively thin flat slab usually

made of reinforced concrete.
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B-4

c. Arch dam. A concrete or masonry dam

which is curved upstream so as to transmit the major

part of the water load to the abutments.

d. Buttress dam. A dam consisting of a

watertight part supported at intervals on the

downstream side by a series of buttresses. A Buttress

dam can take many forms, such as a flat slab or a

massive head buttress.

e. Cofferdam. A temporary structure enclosing

all or part of the construction area so that construction

can proceed in the dry. A diversion cofferdam diverts

a stream into a pipe, channel, tunnel, or other

watercourse.

f. Crib dam. A gravity dam built up of boxes,

crossed timbers, or gabions filled with earth or rock.

g. Diversion dam. A dam built to divert water

from a waterway or stream into a different watercourse.

h. Double curvature arch dam. An arch dam

which is curved vertically as well as horizontally.

i. Earth dam. An embankment dam in which

more than 50 percent of the total volume is formed of

compacted earth material generally smaller than

3-inch size.

j. Embankment dam. Any dam constructed of

excavated natural materials or of industrial waste

materials.

k. Gravity dam. A dam constructed of

concrete and/or masonry which relies on its weight

and internal strength for stability.

l. Hollow gravity dam. A dam constructed of

concrete and/or masonry on the outside but having a

hollow interior and relying on its weight for stability.

m. Hydraulic fill dam. An earth dam

constructed of materials, often dredged, which are

conveyed and placed by suspension in flowing water.

n. Industrial waste dam. An embankment

dam, usually built in stages, to create storage for the

disposal of waste products from an industrial process.

The waste products are conveyed as fine material

suspended in water to the reservoir impounded by the

embankment. The embankment may be built of

conventional materials but sometimes incorporates

suitable waste products.

o. Masonry dam. Any dam constructed mainly

of stone, brick, or concrete blocks jointed with

mortar. A dam having only a masonry facing should

not be referred to as a masonry dam.

p. Mine tailings dam. An industrial waste dam

in which the waste materials come from mining

operations or mineral processing.

q. Multiple arch dam. A buttress dam

composed of a series of arches for the upstream face.

r. Overflow dam. A dam designed to be

overtopped.

s. Regulating dam. A dam impounding a

reservoir from which water is released to regulate the

flow downstream.

t. Rockfill dam. An embankment dam in

which more than 50 percent of the total volume is

composed of compacted or dumped cobbles,

boulders, rock fragments, or quarried rock generally

larger than 3-inch size.

u. Roller-compacted concrete dam. A

concrete gravity dam constructed by the use of a dry

mix concrete transported by conventional

construction equipment and compacted by rolling,

usually with vibratory rollers (EM 1110-2-2006,

Hansen and Reinhardt 1991).1

____________________________

References cited in the appendixes are listed in 1

Appendix A.

v. Rubble dam. A stone masonry dam in

which the stones are unshaped or uncoursed.

w. Saddle dam (or dike). A subsidiary dam of

any type constructed across a saddle or low point on

the perimeter of a reservoir.
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B-5

x. Tailings dam. See mine tailings dam.

Dam failure

The uncontrolled release of impounded water. It is

recognized that there are lesser degrees of failure and

that any malfunction or abnormality outside the

design assumptions and parameters which adversely

affect a dam's primary function of impounding water

is properly considered a failure. They are, however,

normally amenable to corrective action.

Dam safety

This term not only covers the safeguarding of human

life and downstream property but also the satisfactory

operation of the structure. The safety of a dam

manifests itself in being free of conditions that could

lead to the deterioration or destruction of the dam.

The margin which separates the actual conditions of a

dam from those leading to its damage or destruction

is a measure of its safety. To be safe, a dam has to

have appropriate reserves, taking into account all

scenarios of normal utilization and exceptional hazard

which it may have to withstand during its life

(International Commission on Large Dams 1987).

Dam safety preparedness

The quality or state of being prepared to deal with

emergency conditions which endanger the structural

integrity of the dam and/or downstream property and

human life.

Design water level

The maximum water elevation including the flood

surcharge that a dam is designed to withstand.

Design wind

The most severe wind that is reasonably possible at a

particular reservoir for generating wind setup and

runup. The determination will generally include the

results of meteorologic studies which combine wind

velocity, duration, direction, and seasonal distribution

characteristics in a realistic manner.

Diaphragm wall (membrane)

A sheet, thin zone, or facing made of an impervious

material such as concrete, steel, wood, or plastic.

Also see core wall.

Dike

See saddle dam.

Diversion channel, canal, or tunnel

A waterway used to divert water from its natural

course. The term is generally applied to a temporary

arrangement, e.g., to by-pass water around a damsite

during construction. "Channel" is normally used

instead of "canal" when the waterway is short.

Drain, blanket

A layer of pervious material placed to facilitate

drainage of the foundation and/or embankment.

Drain, chimney

A vertical or inclined layer of pervious material in an

embankment to facilitate and control drainage of the

embankment fill.

Drain, toe

A system of pipe and/or pervious material along the

downstream toe of a dam used to collect seepage

from the foundation and embankment and convey it

to a free outlet.

Drainage area

The area which drains to a particular point on a river

or stream.

Drainage curtain

Also called drainage wells or relief wells. A line of

vertical wells or boreholes to facilitate drainage of the

foundation and abutments and to reduce water

pressure.

Drawdown

The difference between a water level and a lower

water level in a reservoir within a particular time.

Used as a verb, it is the lowering of the water surface.

Earthquake

A sudden motion or trembling in the earth caused by

the abrupt release of accumulated stress along a fault.

Earthquake, Maximum Credible (MCE)

The most severe earthquake that can be expected to

occur at a given site on the basis of geologic and

seismological evidence.

Earthquake, Maximum Design (MDE)
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B-6

A postulated seismic event, specified in terms of

specific bedrock motion parameters at a given site,

which is used to evaluate the seismic resistance of

man-made structures or other features at the site.

Earthquake, Operating Basis (OBE)

The earthquake(s) for which the structure is designed

to resist and remain operational. It reflects the level

of earthquake protection desired for operational or

economic reasons and may be determined on a

probabilistic basis considering the regional and local

geology and seismology.

Earthquake, Safety Evaluation (SEE)

The earthquake, expressed in terms of magnitude and

closest distance from the dam site or in terms of the

characteristics of the time history of free-field ground

motions, for which the safety of the dam and critical

structures associated with the dam are to be evaluated.

In many cases, this earthquake will be the maximum

credible earthquake to which the dam will be

exposed. However, in other cases where the possible

sources of ground motion are not easily apparent, it

may be a motion with prescribed characteristics

selected on the basis of a probabilistic assessment of

the ground motions that may occur in the vicinity of

the dam. To be considered safe, it should be

demonstrated that the dam can withstand this level of

earthquake shaking without release of water from the

reservoir.

Earthquake, synthetic

Earthquake time history records developed from

mathematical models that use white noise, filtered

white noise, and stationary and nonstationary filtered

white noise, or theoretical seismic source models of

failure in the fault zone. (White noise is random

energy containing all frequency components in equal

proportions. Stationary white noise is random energy

with statistical characteristics that do not vary with

time).

Embankment

A raised structure to hold back water or to carry a

roadway.

Emergency

An emergency, in terms of dam operation, is a

condition which develops unexpectedly, endangers

the structural integrity of the dam and/or downstream

property and human life, and requires immediate

action.

Emergency Action Plan (EAP)

A plan of action to be taken to reduce the potential for

property damage and loss of life in an area affected

by a dam failure or large flood.

Energy dissipator

A device constructed in a waterway to reduce the

kinetic energy of fast flowing water.

Epicenter

The point on the earth's surface located vertically

above the point of origin of an earthquake.

Fault

A fracture or fracture zone in the earth crust along

which there has been displacement of the two sides

relative to one another.

Fault, active

A fault which, because of its present tectonic setting,

can undergo movement from time to time in the

immediate geologic future.

Fault, capable

An active fault that is judged capable of producing

macroearthquakes and exhibits one or more of the

following characteristics:

a. Movement at or near the ground surface at

least once within the past 35,000 years.

b. Macroseismicity (3.5 magnitude Richter or

greater) instrumentally determined with records of

sufficient precision to demonstrate a direct

relationship with the fault.

c. A structural relationship to a capable fault

such that movement on one fault could be reasonably

expected to cause movement on the other.

d. Established patterns of microseismicity

which define a fault, with historic macroseismicity

that can reasonably be associated with the fault.
EP 1110-2-13

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B-7

Fetch

The straight line distance across a body of water

subject to wind forces. The fetch is one of the factors

used in calculating wave heights in a reservoir.

Filter (filter zone)

One or more layers of granular material graded

(either naturally or by selection) so as to allow

seepage through or within the layers while preventing

the migration of material from adjacent zones.

Flashboards

Structural members of timber, concrete, or steel

placed in channels or on the crest of a spillway to

raise the reservoir water level but that may be quickly

removed in the event of a flood.

Flip bucket

An energy dissipator located at the downstream end

of a spillway and shaped so that water flowing at a

high velocity is deflected upwards in a trajectory

away from the foundation of the spillway.

Flood

A temporary rise in water levels resulting in

inundation of areas not normally covered by water.

May be expressed in terms of probability of

exceedance per year such as one percent chance flood

or expressed as a fraction of the probable maximum

flood or other reference flood.

Flood routing

A process of determining progressively over time the

amplitude of a floodwave as it moves past a dam or

downstream to successive points along a river or

stream.

Flood, antecedent

A flood or series of floods assumed to occur prior to

the occurrence of an inflow design flood.

Flood, base safety standard (BSS)

The inflow design flood where there is no significant

increase in adverse consequences from dam failure

compared to non-failure adverse consequences.

Flood, Safety Evaluation (SEF)

The largest flood for which the safety of a dam and

appurtenant structure is to be evaluated.

Flood, Inflow Design (IDF)

The flood used in the design of a dam and its

appurtenant works particularly for sizing the spillway

and outlet works, and for determining maximum

temporary storage and height of dam requirements.

Flood, Probable Maximum (PMF)

The most severe flood that is considered reasonably

possible at a site as a result of meteorologic and

hydrologic conditions.

Floodplain

An area adjoining a body of water or natural stream

that has been or may be covered by floodwater.

Freeboard

Vertical distance between the design water level and

the top of dam.

Full pool

The reservoir level that would be attained when the

reservoir is fully utilized for all project purposes,

including flood control.

Gallery

A passageway in the body of a dam used for

inspection, foundation grouting, and/or drainage.

Gantry crane

A fixed or traveling bent-supported crane for

handling heavy equipment.

Gate

A movable, watertight barrier for the control of water

in a waterway.

a. Bascule gate. See flap gate.

b. Bulkhead gate. A gate used either for

temporary closure of a channel or conduit before

dewatering it for inspection or maintenance or for

closure against flowing water when the head

difference is small, e.g., for diversion tunnel closure. 

c. Crest gate (spillway gate). A gate on the

crest of a spillway to control the discharge or

reservoir water level.

d. Drum gate. A type of spillway gate

consisting of a long hollow drum. The drum may be
EP 1110-2-13

28 Jun 96

B-8

held in its raised position by the water pressure in a

flotation chamber beneath the dam.

e. Emergency gate. A standby or auxiliary

gate used when the normal means of water control is

not available. Sometimes referred to as guard gate.

f. Fixed wheel gate (fixed roller gate or fixed

axle gate). A gate having wheels or rollers mounted

on the end posts of the gate. The wheels bear against

rails fixed in side grooves or gate guides.

g. Flap gate. A gate hinged along one edge,

usually either the top or bottom edge. Examples of

bottom-hinged flap gates are tilting gates and fish

belly gates so called from their shape in cross section.

h. Flood gate. A gate to control flood release

from a reservoir.

i. Outlet gate. A gate controlling the flow of

water through a reservoir outlet.

j. Radial gate (tainter gate). A gate with a

curved upstream plate and radial arms hinged to piers

or other supporting structure.

k. Regulating gate (regulating valve). A gate

or valve that operates under full pressure flow

conditions to regulate the rate of discharge.

l. Roller drum gate. See drum gate.

m. Roller gate (stoney gate). A gate for large

openings that bears on a train of rollers in each gate

guide.

n. Skimmer gate. A gate at the spillway crest

whose prime purpose is to control the release of 

debris and logs with a limited amount of water. It is

usually a bottom hinged flap or Bascule gate.

o. Slide gate (sluice gate). A gate that can be

opened or closed by sliding in supporting guides.

Gate chamber 

Also called valve chamber. A room from which a

gate or valve can be operated, or sometimes in which

the gate is located.

Geotextiles

Any fabric or textile (natural or synthetic) when used

as an engineering material in conjunction with soil,

foundations, or rock. Geotextiles have the following

uses: drainage, filtration, separation of materials,

reinforcement, moisture barriers, and erosion

protection.

Groin

The area along the contact (or intersection) of the face

of a dam with the abutments.

Grout

A fluidized material that is injected into soil, rock,

concrete, or other construction material to seal

openings and to lower the permeability and/or

provide additional structural strength. There are four

major types of grouting materials: chemical, cement,

clay, and bitumen.

Grout curtain

One or more zones, usually thin, in the foundation

into which grout is injected to reduce seepage under

or around a dam.

Grout blanket

An area of the foundation systematically grouted to a

uniform shallow depth.

Grout cap

A concrete pad constructed to facilitate subsequent

pressure grouting of the grout curtain.

Hazard classification

The rating for a dam based on the potential

consequences of failure. The rating is based on

potential for loss of life and damage to property that

failure of that dam could cause. Such classification is

related to the amount of development downstream of

a dam.

Head, static

The vertical distance between two points in a fluid.

Head, velocity

The vertical distance that would statically result from

the velocity of a moving fluid.

Headrace
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B-9

A free-flow tunnel or open channel that conveys

water to the upper end of a penstock; hence, the terms

"headrace tunnel" and "headrace canal."

Heel

The junction of the upstream face of a gravity or arch

dam with the ground surface. For an embankment

dam the junction is referred to as the upstream toe of

the dam.

Height, above ground

The maximum height from natural ground surface to

the top of a dam.

Height, hydraulic

The vertical difference between the maximum design

water level and the lowest point in the original

streambed.

Height, structural

The vertical distance between the lowest point of the

excavated foundation to the top of the dam.

Hydrograph, breach or dam failure

A flood hydrograph resulting from a dam breach.

Hydrograph, flood

A graphical representation of the flood discharge with

respect to time for a particular point on a stream or

river.

Hydrograph, unit

A hydrograph with a volume of 1 inch of runoff

resulting from a storm of a specified duration and

areal distribution. Hydrographs from other storms of

the same duration and distribution are assumed to

have the same time base but with ordinates of flow in

proportion to the runoff volumes.

Hypocenter

The point or focus within the earth which is the center

of an earthquake and the origin of its elastic waves.

Inclinometer

An instrument, usually consisting of a metal or plastic

tube inserted in a drill hole and a sensitized monitor

either lowered into the tube or fixed within the tube.

This measures at different points the tube's inclination

to the vertical. By integration, the lateral position at

different levels of the tube may be found relative to a

point, usually the top or bottom of the tube, assumed

to be fixed. The system may be used to measure

settlement during embankment construction

(Bartholomew, Murray, and Goins 1987). A

reference benchmark is used to establish the top of

the inclinometer casing. The instrument probe is

lowered to each slip joint in the casing, and the depth

to each joint is read directly off the tape. Settlement

measurements are made as each section of casing is

added during embankment construction. 

Initial reservoir filling

A deliberate impoundment to meet project purposes

(a continuing process as successively higher pools are

attained for flood control projects).

Instrumentation

An arrangement of devices installed into or near dams

(i.e., piezometers, inclinometers, strain gages,

measurement points, etc.) which provide for

measurements that can be used to evaluate the

structural behavior and performance parameters of

the structure.

Intake

Any structure in a reservoir, dam, or river through

which water can be discharged.

Inundation map

A map delineating the area that would be flooded by a

particular flood event.

Length of dam

The length along the top of the dam. This also

includes the spillway, powerplant, navigation lock,

fish pass, etc., where these form part of the length of 

the dam. If detached from the dam these structures

should not be included.

Liquefaction

A condition whereby soil undergoes continued

deformation at a constant low residual stress or with

low residual resistance, due to the buildup and

maintenance of high pore water pressures, which

reduces the effective confining pressure to a very low

value. Pore pressure buildup leading to liquefaction

may be due either to static or cyclic stress applications
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and the possibility of its occurrence will depend on

the void ratio or relative density of a cohesionless or

slightly cohesive soil and the confining pressure.

Logboom

A chain of logs, drums, or pontoons secured end to

end and floating on the surface of a reservoir so as to

divert floating debris, trash, and logs.

Maximum flood control level

The highest elevation of the flood control storage.

Maximum pool

The highest pool elevation resulting from the inflow

design flood.

Maximum wave

The highest wave in a wave group.

Minimum operating level

The lowest level to which the reservoir is drawn

down under normal operating conditions.

Observation well

A hole used to observe the groundwater surface at

atmospheric pressure within soil or rock.

Outlet

An opening through which water can be discharged.

Outlet works

A device to provide controlled releases from a

reservoir.

Parapet wall

A solid wall built along the top of a dam (upstream or

downstream edge) used for ornamentation, for safety 

of vehicles and pedestrians, or to prevent overtopping

caused by wave runup.

Penstock

A pressurized pipeline or shaft between the reservoir

and hydraulic machinery.

Phreatic surface

The free surface of water seeping at atmospheric

pressure through soil or rock.

Piezometer

An instrument used for measuring fluid pressure (air

or water) within soil, rock, or concrete.

Piping

The progressive development of internal erosion by

seepage.

Plunge pool

A natural or artificially created pool that dissipates the

energy of free falling water.

Pore water pressure

The interstitial pressure of water within a mass of soil,

rock, or concrete.

Probability

The likelihood of an event occurring.

Probable Maximum Precipitation (PMP)

Theoretically, the greatest depth of precipitation for a

given duration that is physically possible over a given

size storm area at a particular geographical location.

Pumped storage reservoir

A reservoir filled entirely or mainly with water

pumped from outside its natural drainage area.

Quality (as related to construction)

Conformance to properly developed requirements.

Quality Assurance (QA)

The procedure by which the Government fulfills its

responsibility to be certain the contractor's quality

control is functioning and the specified end product is

realized.

Quality Management

All control and assurance activities instituted to

achieve the product quality established by the contract

requirements.

Reservoir

A body of water impounded by a dam and in which

water can be stored.

Reservoir regulation (or operating) procedure

Operating procedures that govern reservoir storage

and releases.
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Reservoir surface area

The area covered by a reservoir when filled to a

specified level.

Riprap

A layer of large uncoursed stone, precast blocks, bags

of cement, or other suitable material, generally placed

on the upstream slopes of an embankment or along a

watercourse as protection against wave action,

erosion, or scour. Riprap is usually placed by

dumping or other mechanical methods and in some

cases is hand placed. It consists of pieces of relatively

large size as distinguished from a gravel blanket.

Risk

The relationship between the consequences resulting

from an adverse event and its probability of

occurrence.

Risk assessment

As applied to dam safety, the process of identifying

the likelihood and consequences of dam failure to

provide the basis for informed decisions on a course

of action.

Rock anchor

A steel rod or cable placed in a hole drilled in rock,

held in position by grout, mechanical means, or both.

In principle, the same as a rock bolt, but usually the

rock anchor is more than 4 meters long.

Rock bolt

A steel rod placed in a hole drilled in rock, held in

position by grout, mechanical means, or both. A rock

bolt can be pretensioned.

Runup

The vertical distance above the setup that the rush of

water reaches when a wave breaks on the dam

embankment.

Seepage

The interstitial movement of water that may take

place through a dam, its foundation, or its abutments.

Significant wave height

The average height of the one-third highest waves of

a given wave group.

Sill

A submerged structure across a river to control the

water level upstream. The crest of a spillway. A

horizontal gate seating, made of wood, stone,

concrete, or metal at the invert of any opening or gap

in a structure; hence, the expressions "gate sill" and

"stoplog sill."

Slope

Inclination from the horizontal. Sometimes referred

to as batter when measured from vertical.

Sluice

An opening for releasing water from below the static

head elevation.

Spillway

A structure over or through which flow is discharged

from a reservoir. If the rate of flow is controlled by

mechanical means such as gates, it is considered a

controlled spillway. If the geometry of the spillway is

the only control, it is considered an uncontrolled

spillway.

Spillway, auxiliary

Any secondary spillway which is designed to be

operated very infrequently and possibly in

anticipation of some degree of structural damage or

erosion to the spillway during operation.

Spillway, primary (or service)

A spillway designed to provide continuous or

frequent releases from a reservoir without significant

damage to either the dam or its appurtenant structures.

Spillway Design Flood (SDF)

See Flood, Inflow Design.

Spillway channel

An open channel or closed conduit conveying water

from the spillway inlet downstream.

Spillway chute

A steeply sloping spillway channel that conveys discharges at supercritical velocities.

Spillway crest
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B-12

The lowest level at which water can flow over or

through the spillway.

Spillway, fuse plug

A form of auxiliary spillway consisting of a low

embankment designed to be overtopped and washed

away during an exceptionally large flood.

Spillway, shaft

A vertical or inclined shaft into which water spills and

then is conveyed through, under, or around a dam by

means of a conduit or tunnel. If the upper part of the

shaft is splayed out and terminates in a circular

horizontal weir, it is termed a bellmouth or morning

glory spillway.

Stilling basin

A basin constructed to dissipate the energy of rapidly

flowing water, e.g., from a spillway or outlet, and to

protect the riverbed from erosion.

Stoplogs

Large logs, timbers, or steel beams placed on top of

each other with their ends held in guides on each side

of a channel or conduit so as to provide a cheaper or

more easily handled means of temporary closure than

a bulkhead gate.

Storage

The retention of water or delay of runoff either by

planned operation, as in a reservoir, or by temporary

filling of overflow areas, as in the progression of a

flood wave through a natural stream channel.

Definitions of specific types of storage in reservoirs

are: 

a. Dead storage. The storage that lies below

the invert of the lowest outlet and that, therefore,

cannot readily be withdrawn from the reservoir.

b. Inactive storage. The storage volume of a

reservoir between the crest of the invert of the lowest

outlet and the minimum operating level.

c. Active storage. The volume of the reservoir

that is available for some use such as power

generation, irrigation, flood control, or water supply.

The bottom elevation is the minimum operating level.

d. Live storage. The sum of the active and the

inactive storage.

e. Reservoir capacity. The sum of the dead

and live storage of the reservoir.

f. Flood surcharge. The storage volume

between the top of the active storage and the design

water level.

Surcharge

Any storage above the full pool.

Tailrace

The tunnel, channel, or conduit that conveys the

discharge from the turbine to the river; hence, the

terms "tailrace tunnel" and "tailrace canal."

Tailwater level

The level of water in the tailrace at the nearest free

surface to the turbine or in the discharge channel

immediately downstream of the dam.

Threshold Flood

The flood that fully utilizes the existing dam, i.e., the

flood that just exceeds the design maximum water

surface elevation at the dam.

Thrust block

A massive block of concrete built to withstand a

thrust or pull.

Toe of dam

The junction of the face of a dam with the ground

surface. For concrete dams, see heel.
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B-13

Top thickness (top width)

The thickness or width of a dam at the level of the top

of dam (excluding corbels or parapets). In general,

the term thickness is used for gravity and arch dams,

and width is used for other dams.

Top of dam

The elevation of the uppermost surface of a dam,

usually a road or walkway excluding any parapet

wall, railing, etc.

Trashrack

A device located at an intake to prevent floating or

submerged debris from entering the intake.

Tunnel

A long underground excavation with two or more

openings to the surface, usually having a uniform

cross section used for access, conveying flows, etc.

Uplift

The uplift pressure in the pores of a material

(interstitial pressure) or on the base of a structure.

Upstream blanket

An impervious blanket placed on the reservoir floor

and abutments upstream of a dam. For an

embankment dam, the blanket may be connected to

the core.

Valve

A device fitted to a pipeline or orifice in which the

closure member is either rotated or moved

transversely or longitudinally in the waterway so as to

control or stop the flow.

a. Hollow jet valve. A device for regulating

high-pressure outlets. Essentially, it is half a needle

valve in which the needle closure member moves

upstream toward the inlet end of the valve to shut off

flow. As there is no convergence at the outlet end,

the flow emerges in the form of an annular cylinder,

segmented by several splitter ribs for admitting air

into the jet interior to prevent jet instability.

b. Regulating sleeve valve. A valve for

regulating high pressure outlets and ensuring energy

dissipation. Inside the valve there is a fixed-cone,

pointed upstream, which ensures dispersion of the jet.

Outside the valve a cylindrical sleeve moves

downstream to shut off flow by sealing on the

periphery of the cone.

Volume of dam

The total space occupied by the materials forming the

dam structure computed between abutments and from

top to bottom of dam. No deduction is made for

small openings such as galleries, adits, tunnels, and

operating chambers within the dam structure.

Portions of powerplants, locks, spillway, etc., should

be included only if they are necessary for the

structural stability of the dam.

Watershed divide

The divide or boundary between catchment areas (or

drainage areas).

Waterstop

A strip of metal, rubber, or other material used to

prevent leakage through joints between adjacent

sections of concrete.

Wave runup

Vertical height above the stillwater level to which 
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B-14

water from a specific wave will run up the face of a

structure or embankment.

Weir

A notch of regular form through which water flows.

a. Weir, broad-crested. An overflow structure

on which the nappe is supported for an appreciable

length in the direction of flow.

b. Weir, measuring. A device for measuring

the rate of flow of water. It generally consists of a

rectangular, trapezoidal, triangular, or other shaped

notch, located in a vertical, thin plate over which

water flows. The height of water above the weir crest

is used to determine the rate of flow.

c. Weir, ogee. A reverse curve, shaped like an

elongated letter "S." The downstream faces of

overflow spillways are often made to this shape.

Wind setup

The vertical rise in the stillwater level at the face of a

structure or embankment caused by wind stresses on

the surface of the water.
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C-1

Appendix C

Design

C-1. Introduction

Dams are unique because the design function can

never be considered finished as long as the dam

remains in place. Because of the many unknowns

usually encountered, construction (and operation)

must be a continuation of design. Foundation and

borrow work during construction provide far better

exploration than is available during design, and

changes which impact safety are common. Design

personnel should visit the site during construction to

confirm that site conditions conform to those assumed

in design or to determine if design changes are

required to suit the actual conditions. Operational

design inspections should continue throughout the

life of the project. The design function includes

planning dam instrumentation to be installed during

construction and/or operation to monitor conditions

that could potentially threaten the safety of the dam

(Federal Emergency Management Agency 1979).

The general design and construction of earth and rock

fill dams are discussed in EM 1110-2-2300 and

EM 1110-2-1911. The design of gravity dams is

given in EM 1110-2-2200.

C-2. Design Review

All designs accomplished by an Engineering District

will be reviewed by an independent, multi-discipline

team. About 80 percent of Corps dam designs are

accomplished internally and about 20 percent are

accomplished externally by contract with private

engineering firms (Federal Emergency Management

Agency 1992b; U.S. Army Corps of Engineers,

Office of the Chief of Engineers 1977).

C-3. Instrumentation Plan

a. General. All Corps of Engineers dams are

required to have an adequate level of instrumentation

to enable the designers to monitor and evaluate the

safety of the structure during the construction period

and under all operating conditions. Visual

observations and the interpretation of instrumentation

data provide the primary means for engineers to

evaluate dam safety. Recently, technology of devices

for measuring seepage, stresses and movements and

pore water pressures in dams has improved

significantly with respect to accuracy, reliability and

economics. The planning, design, and layout of an

instrumentation program is an integral part of the

project design. Guidance on the selection and use of

various types of instrumentation for earth and rockfill

dams is given in EM 1110-2-2300 and EM 1110-2-

1908. Guidance on the instrumentation for concrete

dams is given in EM 1110-2-1908 and EM 1110-2-

4300 (see also Lindsey et al. 1986, Keeter et al. 1986,

Currier and Fenn 1986, O'Neil 1989). Additional

information on instrumentation of dams is available

(United States Committee on Large Dams 1984 and

1986, Colorado Division of Disaster Emergency

Services 1987, Federal Energy Regulatory

Commission 1991, Carpenter et al. 1988). 

b. Types of instrumentation. The type,

number, and location of required instrumentation

depend on the complexity of the project. For earth

and rockfill dams, the types of measurements

generally include the following (EM 1110-2-2300

and EM 1110-2-1908):

(1) Piezometers (open tube, such as the

Casagrande type, electrical, vibrating wire, or

occasionally closed systems; located in the

foundation, abutment, and/or embankment).

(2) Surface monuments.

(3) Settlement plates within the embankment.

(4) Inclinometers (slope indicators).

(5) Movement indicators (at conduit joints,

outlet works, and intake tower).

(6) Internal vertical and horizontal movement

and strain indicators.

(7) Earth pressure cells.
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C-2

(8) Strong motion accelerometers (in areas of

seismic activity).

(9) Weirs, flow meters and flumes to measure

seepage clarity and quantity.

For concrete dams, the types of measurements (and

instruments) include (EM 1110-2-2200 and

EM 1110-2-4300):

(1) Strain and deflection (internal and/or

external gages).

(2) Crack or joint movement (internal and/or

external gages).

(3) Stress and pressure (stress meter, pressure

gage, pressure cell).

(4) Uplift pressure (standpipe and/or diaphragm

uplift cell, water level indicator).

(5) Hydraulic leakage from foundation drains,

joint drains and face drains (v-notch weir and/or

critical depth meter).

(6) Plumbness and levelness (plumb lines,

optical plummets, electolevel and water level meter).

(7) Alignment, settlement, and distance (laser,

theodolite, triangulation, trilateration and electronic

distance meters).

(8) Seismic time history and magnitude (strong

motion and peak reading accelerometers and

hydrodynamic pressure gages).

(9) Temperature (resistance thermometer and

thermocouples).

c. Automatic data acquisition. Consideration

should be given to providing a computer-based

automated data acquisition system (ADAS) to

provide cost-effective real time data collection from

the dam. General guidance for developing an ADAS

for earth and rockfill dams is presented in

Appendix D of EM 1110-2-2300. A comprehensive

review of ADAS for concrete structures was made

under the Corps of Engineers Repair, Evaluation,

Maintenance, and Rehabilitation (REMR) Program

(Lindsey et al. 1986, Keeter et al. 1986, Currier and

Fenn 1986, O'Neil 1989). Topics covered include

design requirements, signal conditioning and

processing, data transmission and reduction, system

installation and maintenance, retrofitting existing

instruments to automation and computer hardware

and software used to drive the automated instruments

and reduce and report the collected data (U.S. Army

Corps of Engineers 1987). A data base for automated

geotechnical and some structural instrumentation at

Federal and non-Federal projects is maintained under

the Corps of Engineers Computer Applications in

Geotechnical Engineering (CAGE) Program.

d. Instrumentation plan and records. During

the initial project design, or reevaluation in the case of

existing structures, the physical properties of the

construction materials, design data, loading

conditions and the appropriate factors of safety will

be utilized to determine the desired threshold limits

for the design condition. Quantitative values will be

established for these limits that can be accurately

translated into measurements that are readily obtained

in the field, which will enable the designers and

operators to evaluate the behavior and performance of

the structure. The threshold limits along with the

predicted performance levels will be addressed in the

project instrumentation design memorandum.

General guidance on preparation of the

instrumentation design memorandum is given in

EM 1110-2-2300 and ER 1110-2-110. ER 1110-2-

1925 prescribes the forms to use in recording instrumentation observations. Additional information on

instrumentation and monitoring is given in Chapter 4.

C-4. Coordination Between Design and

Construction

Close coordination between design and construction

personnel is necessary to thoroughly orient the

construction personnel as to the project design intent;

ensure that new field information, acquired during

construction, is assimilated into the design; and

ensure that the project is constructed according to the

intent of the design (U.S. Army Corps of Engineers,

Office of the Chief of Engineers 1977). 
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C-3

a. Report on engineering considerations and

instructions to field personnel. Design personnel

(geologists, geotechnical engineers, structural

engineers, etc.) will prepare a report to aid the

construction engineers in supervision and inspection

of the construction of the dam (ER 1110-2-1150). 

b. P r e c o n s t r u c t i o n o r i e n t a t i o n .

Preconstruction orientation for the construction

engineers by the designers is necessary for the

construction engineers to be aware of the design

philosophies and assumptions regarding site

conditions and function of project structures, and to

understand the design engineers' intent concerning

technical provisions in the P&S (Federal Emergency

Management Agency 1979). 

c. Construction milestones which require visit

by designers. Visits to the site by design and design

review personnel are required to ensure the following

(ER 1110-2-112, ER 1110-2-1150):

(1) Site conditions throughout the construction

period are in conformance with design assumptions

and principles as well as contract P&S.

(2) Project personnel are given assistance in

adapting project designs to actual site conditions as

they are revealed during construction.

(3) Any engineering problems not fully assessed

in the original design are observed, evaluated, and

appropriate action taken.

Specifically, site visits are required when the

following occur (ER 1110-2-112):

(1) Excavation of cutoff trenches, foundations,

and abutments for dams and appurtenant structures.

(2) Excavation of tunnels.

(3) Excavation of borrow areas and placement of

embankment dam materials early in the construction

period.

(4) Observation of field conditions that are

significantly different from those assumed during

design.

d. Ensure project is constructed according to

intent of design. The Corps of Engineers has several

cost-saving programs. One of these programs which

can affect dam safety is Value Engineering (VE).

The VE process provides for a multi-discipline team

of engineers to develop alternative designs for some

portion of the project. The construction contractor

can also submit VE proposals. Any VE proposal

affecting the design is to be evaluated by design

personnel prior to implementation to determine the

technical adequacy of the proposal. VE proposals

must not adversely affect the long-term performance

or condition of the dam. A potential safety problem

exists if design personnel do not have the opportunity

for evaluation (U.S. Army Corps of Engineers, Office

of the Chief of Engineers 1977).
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D-1

Appendix D

Construction

D-1. General

Construction is a critical phase in achieving a safe dam

because operational problems often go back to mistakes

made in design and construction (James 1990). Projects

must be continuously evaluated and "re-engineered," as

required, during construction, to ensure that the final

design is compatible with conditions encountered

during construction (Federal Emergency Management

Agency 1979). Construction considerations of earth

and rock fill dams are discussed in EM 1110-2-2300

and EM 1110-2-1911. 

D-2. Construction/Design Interface

Dam safety is an integral part of the planning, design,

construction, and operation of a dam.

Construction/design interface is essential. This is

accomplished through the report on engineering

considerations and instructions to field personnel,

preconstruction orientation for the construction

engineers by the designers, and required visits to the

site by the designers. 

D-3. Problems to Watch for During

Construction

Specific problems with safety implications to watch for

during construction include (James 1990):

a. Contacts between fill and rock or concrete.

(1) Problems due to dissimilar compressibility

leading to differential settlement and voids or cracks

within the embankment.

(2) Critical areas at rock abutments (particularly

for steep slopes or slope breaks), spillway contacts,

adjacent to conduits, and at contacts with existing fill

which have had time to undergo settlement.

(3) Problems of placement and compaction

complicated because of restricted access.

(4) Initial fill placement on rock foundation.

b. Failure to detect and remove localized areas

of soft foundation material.

(1) Potential differential settlement and cracking.

(2) Important factor in stability of dam and

foundation.

c. Preparation and treatment of cutoffs in

foundations and abutments - one of the most important

factors in embankment dam construction.

(1) Failure to achieve an adequate cutoff to

sound rock or an impervious strata.

(2) Failure to achieve adequate reduction in

seepage volume or pressure with grout curtain or to seal

off large channels or voids.

(3) Failure to achieve adequate surface treatment

of joints, potholes, treatment of overhangs, loose rock

on abutments, or inadequate bond between

embankment and foundation.

 

d. Construction problems during installation of

drains and filters.

(1) Piping can result from failure to achieve

filter criteria due to segregation of material which may

occur in transition to rockfill or in exit details.

(2) Inadequate drainage capacity because of

improper gradation, dirty (excessive amount of fines)

materials, material breakdown during placement, or

contamination of the filter with impervious material

from the adjacent core due to traffic or due to surface

erosion caused by rainfall.

e. Failure to detect critical zones such as voids

or strata, or lenses, of pervious materials in foundations

without cutoffs.

(1) Inadequate or no pressure relief.
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D-2

(2) Lack of control over exits.

D-4. Obtaining Quality Construction

a. Definitions (ER 1180-1-6).

(1) Quality is conformance to properly

developed requirements. In the case of construction

contracts, these requirements are established by the

contract specifications and drawings.

(2) Quality management is all control and

assurance activities instituted to achieve the product

quality established by the contract requirements.

(3) Contractor quality control (CQC) is the

construction contractor's system to manage, control and

document his own, his supplier's and his subcontractor's

activities to comply with contract requirements.1

(4) Quality Assurance (QA) is the procedure by

which the Government fulfills its responsibility to be

certain the CQC is functioning and the specified end

product is realized.

b. Policy. Obtaining quality construction is a

combined responsibility of the construction contractor

and the Government. The contract documents establish

the level of quality required in the project to be

constructed. In contracts of $1,000,000 or greater,

detailed CQC will be applied and a special clause will

be included in the contract. Guidance in preparing this

clause is given in Appendix A of ER 1180-1-6. QA is

required on all construction contracts. The extent of

assurance is commensurated with the value and

complexity of the contracts involved. QA testing is

required (ER 1180-1-6). 

c. Contractor responsibility. Contractors shall

be responsible for all activities necessary to manage,

____________________________

 Additional information is given in EP 715-1-2, "A 1

Guide to Effective Contractor Quality Control (CQC)"

and International Commission on Large Dams

Bulletin 56 "Quality Control for Fill Dams" (International Commission on Large Dams 1986).

control, and document work so as to ensure compliance

with the contract plans and specifications (P&S).

Contractor's responsibility includes ensuring that

adequate quality control services are provided for work

accomplished by his organization, suppliers,

subcontractors, technical laboratories and consultants.

For contracts of $1,000,000 or greater, contractors will

be required to prepare a quality control plan (see

Appendix A of ER 1180-1-6) (ER 1180-1-6). 

d. Government responsibility. QA is the

process by which the Government assures end product

quality. This process starts well before construction and

includes reviews of the P&S for biddability and

constructibility, plan-in-hand site reviews, coordination

with using agencies or local interests, establishment of

performance periods and quality control requirements,

field office planning, preparation of QA plans, reviews

of quality control plans, enforcement of contract clauses

and acceptance of completed construction (ER 1180-1-

6). 

e. Quality assurance for procedural

specifications. Some QA testing in the case of

earthwork embankment and concrete dam structures

must be conducted continuously. A comprehensive QA

testing program by the Government is necessary when

specifications limit the contractor to prescriptive

procedures leaving the responsibility for end product

quality to the Government (ER 1180-1-6). 

D-5. Construction Records and Reports

a. General. Engineering data relating to project

structures will be collected and permanently retained at

the project site as specified in Appendix A of ER 1110-

2-100 and EM 1110-2-2300. This information has

many uses such as determining the validity of claims

made by construction contractors, designing future

alterations and additions to the structure, familiarizing

new personnel with the project and providing guidance

for designing comparable future projects. These

documents will include as many detailed photographs

as necessary. This information is crucial to dam safety

because it provides the basis for analysis and remedial

action in the event of future distress.
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D-3

b. Field control data. As required byEM 1110-

2-2300, records including field control data on methods

of compaction, in-place unit weight and moisture

content, piezometers, surface monuments and slope

indicators are kept for use in construction, operation

and maintenance of the project. Instructions regarding

specific forms to use for field data control are given in

ER 1110-2-1925.

c. As-constructed drawings. As construction of

a project progresses, plans will be prepared showing the

work as actually constructed. Changes may be

indicated in ink on prints of the construction drawings

or the tracings may be revised and new prints made to

show the work as constructed, as specified in ER 1110-

2-1200. 

d. Embankment criteria and foundation report.

Earth and earth-rockfill dams require an embankment

criteria and foundation report to provide a summary of

significant design assumptions and computations,

specification requirements, construction procedures,

field control and record control test data and

embankment performance as monitored by

instrumentation during construction and during initial

reservoir filling. This report is usually written by

persons with first hand knowledge of the project design

and construction. The written text is brief with the main

presentation consisting of a set of identified

construction photographs, data summary tables, and as

constructed drawings. This report is important to dam

safety because it provides in one volume the significant

information needed by engineers to familiarize

themselves with the project and to reevaluate the

embankment in the event unsatisfactory performance

occurs (see ER 1110-2-1901). 

e. Construction foundation report. In addition

to an embankment criteria and foundation report, all

major and unique dams require a construction

foundation report to be completed within 6 months after

completion of the project or part of the project for

which the report is written (see Appendix A of

ER 1110-1-1801 for a suggested outline for foundation

reports). This report documents observations of

subsurface conditions encountered in all excavations

and provides the most complete record of subsurface

conditions and treatment of the foundation. The

construction foundation report is important to dam

safety because it saves valuable time by eliminating the

need to search through voluminous construction records

of the dam to find needed information to use in

planning remedial action should failure or partial failure

of a structure occur as a result of foundation

deficiencies.

f. Photographs and video tape taken during

construction. Embankment criteria and foundation and

construction foundation reports should be

supplemented by photographs that clearly depict

conditions existing during embankment and foundation

construction. Routine photographs should be taken at

regular intervals, and additional pictures should be

taken of items of specific interest, such as the

preparation of foundations and dam abutments. For

these items, color photographs should be taken. The

captions of all photographs should contain the name of

the project, the date on which the photograph was

taken, the identity of the feature being photographed

and the location of the camera. In reports containing a

number of photographs, an alternative would be an

index map with a circle indicating the location of the

camera with an arrow pointing in the direction the

camera was pointing, with each location keyed to the

numbers on the accompanying photographs (EM 1110-

2-1911). Consideration should be given to using video

tape where possible to document construction of the

dam.
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E-1

Appendix E

Research and Development

E-1. Introduction

a. General. A strong research and development

effort is necessary to reduce the uncertainties still

present in dam engineering. Few research projects to

date, exceptions are in risk analysis and hydrologic

design parameters, have been undertaken in the name of

dam safety. Alternately, many research projects may

provide a better understanding of site investigation and

characterization, geotechnical and/or hydraulic

considerations, construction methods, natural

phenomenon and structural performance, all of which

contribute to the safety of dams (Federal Emergency

Management Agency 1979, Interagency Committee on

Dam Safety Research Subcommittee 1982). 

b. Definition. The Interagency Committee on

Dam Safety (ICODS) Research Subcommittee has

taken a liberal approach and defined dam safety

research as that research which can help enhance the

safety of dams (Interagency Committee on Dam Safety

Research Subcommittee 1982). 

c. Assessment of needs in dam safety research.

(1) Interagency Committee on Dam Safety Report.

In 1980 the Research Subcommittee of ICODS was

organized and charged to identify current dam safety

research to develop a 5-year projection of research

needs and to establish priorities for the research needs.

In a report issued in May 1982, the Research

Subcommittee, for the first time, presented consolidated

information on research projects and needed dam safety

research (Federal Emergency Management Agency

1982). 

(2) Electric Power Research Institute and Federal

Emergency Management Agency Workshop. A

workshop on dam safety needs, sponsored by the

Electric Power Research Institute (EPRI) and the

Federal Emergency Management Agency (FEMA) was

held in Denver, CO, in July 1985 to study research

needs in dam safety. The workshop excluded seismic

disturbance predictions and their influence on dam

safety and hydrological considerations that would lead

to predictions of the probable maximum flood that the

dam might have to withstand because these topics had

received extensive treatment in a previous study by the

National Research Council of the National Academy of

Sciences issued in March 1985 (National Research

Council 1985). 

(a) The most important needs for dam safety

research identified by the workshop participants

included (Karadi and Landis 1986) overtopping of

dams (primarily earth and rock-fill dams), and the

development of rational uplift criteria for concrete

dams. 

(b) Almost as much importance was placed on a

second set of issues including development of a data

base for earth and rock-fill dams and technology

transfer, research on seepage and permeability as well

as grouting, development of prediction techniques for

inception and progression of erosion, evaluation of

seismic behavior of concrete dams, and experimentation

on natural and synthetic materials to define erosion and

erosion control parameters. 

d. Overview of dam safety research. The

Government, industry and the academic community

recognize the necessity for research in dam safety.

During the 1980's numerous dam safety research was

initiated to study problems such as spillway adequacy,

foundation defects, and piping (Thomas 1987). 

E-2. Dam Safety Research in the Corps of 

Engineers

a. Civil works program. The Corps of Engineers

for many years has had an extensive research program

seeking solutions to problems encountered in its civil

works program for water resource development

(Federal Emergency Management Agency 1988b). 

b. Repair, Evaluation, Maintenance, and

Rehabilitation Program. The Corps of Engineers has

recently completed a 6-year major multidisciplinary

research and development program entitled "Repair,

Evaluation, Maintenance, and Rehabilitation (REMR)

Program." The primary objective of the REMR

program was to identify and develop effective and
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E-2

affordable technology for maintaining and extending

the service life of existing Corps civil works structures.

The REMR program covered a wide range of

techniques for inspection, evaluation, repair, and

rehabilitation of hydraulic structures including dams.

Many of the research studies provide knowledge and

techniques needed in many aspects of dam safety. An

overview of the REMR program is available (U.S.

Army Corps of Engineers 1990). A follow-on 7-year

REMR-II program was started in Fiscal Year 1992 to

address new and different needs identified by Corps

field offices. Research conducted under REMR-II will

have applicability to dam safety.

c. Dam Safety Risk Analysis Research Program.

This program, conducted from 1984 to 1990, was managed by the Corps' Institute for Water Resources. The

program consisted of numerous work units for dam

safety risk analyses, including a work unit for

hydrologic risk analyses conducted at the Corps'

Hydrologic Engineering Center (Stakhiv and Moser

1986; Federal Emergency Management Agency 1988b;

Duscha 1984, 1986; Von Thun 1984; Lave, ResendizCarrillo, and McMichael 1990). Studies of

socioeconomic considerations and multiobjective risk

partitioning in dam safety risk analysis were conducted

(Cochrane, Ferrell-Dillard, Baumann 1987; Haimes et

al. 1988). 

E-3. Dam Safety Research by Other Federal 

Agencies

Significant effort goes into research on dam safety by

other Federal agencies. General exchange of

information and coordination of efforts are discussed in

paragraph E-4.

a. Agencies. The agencies that manage the major

part of Federal research and development activities

related to dam safety (Federal Emergency Management

Agency 1988b) are U.S. Army Corps of Engineers,

Bureau of Reclamation, and Federal Emergency

Management Agency.

b. Programs. Specialized research and

development programs are conducted or sponsored by

the Soil Conservation Service and the Electric Power

Research Institute.

E-4. Coordination Among Federal Agencies

a. Technology. The technology for design,

construction, operation, and maintenance of dams is

constantly changing due to new developments from

research; unique experience with projects under design,

construction, or operation; new developments in

laboratory testing and equipment and/or field

investigation practices and procedures; and

development of new analytical methods (U.S. Army

Corps of Engineers, Office of the Chief of Engineers

1977; Federal Coordinating Council for Science,

Engineering and Technology 1978).

b. Federal Agency exchange. Exchange of

information and coordination of efforts on dam safety

research among Federal agencies is accomplished

through the ICODS Subcommittee on Safety Research

and through the biennial Interagency Research

Coordination Conferences (Federal Emergency

Management Agency 1979, 1988b).

E-5. Transfer and Integration of New

Technology

a. Transfer of new technology. There is no

single, most successful, method of technology transfer.

What works well for one type of technology and one

type of user may not work as well for other users.

Therefore, a successful technology transfer effort must

use a combination of methods (U.S. Army Corps of

Engineers 1990). Methods used to transfer dam safety

technology include articles in technical journals,

technical reports (written and/or video), information

exchange bulletins, newsletters or technical notes,

workshops and conferences, demonstrations of new

technology on site, and electronic bulletin boards.

b. Integration of new technology. Various

methods are used to integrate new technology into dam

safety. Some of those methods are input to engineer

manuals, engineer regulations, engineer technical

letters, etc., PROSPECT course on dam safety, TADS

program, training program for operations and

maintenance personnel, use of experts or consultants,

and computer data bases and expert systems.

U.S. Government Printing Office: 1996-412-340/50421