Aging Infrastructure: Dam Safety

Aging Infrastructure: Dam Safety

Order Code RL33108
Aging Infrastructure: Dam Safety
Updated March 25, 2008
Nic Lane
Analyst in Natural Resources Policy
Resources, Science, and Industry Division

Aging Infrastructure: Dam Safety
Summary
While dams have multiple benefits (balanced against financial and
environmental costs), they can also present a risk to public safety and economic
infrastructure. This risk stems from two sources: the possibility of a dam failure and
the damage it would cause. Although dam failures are infrequent, age, construction
deficiencies, inadequate maintenance, and seismic or weather events contribute to the
possibility. To reduce the risk, regular inspections are necessary to identify potential
problems. Corrective action can then be taken to remedy those deficiencies. Congress
is often called upon to fund remedial actions, as a way to prevent the larger
catastrophes. The 110th Congress will likely see proposals for improving dam safety
and may oversee existing safety programs.
To identify deficiencies that could cause dam failures, the federal government
established inspection requirements for the nation’s federal dams. Once deficiencies
are identified, most agencies finance repairs through their operation and maintenance
accounts. Funding mechanisms vary for larger rehabilitation activities. At the
Bureau of Reclamation, for example, most larger repairs are conducted with annual
appropriations to its dam safety program. At some other agencies, dam rehabilitation
must compete with other construction projects for funding.
The federal agencies with dam safety responsibilities include the Tennessee
Valley Authority, the Federal Energy Regulatory Commission (FERC), and the
Departments of Agriculture, Defense, Energy, the Interior, Labor, and State. At
nonfederal dams, safety is generally a state responsibility, though some federal
assistance has been provided. The National Dam Safety Program, which is
authorized through FY2011 by P.L. 109-460, helps states improve their dam safety
programs and train inspectors. In addition, FERC and the Department of Labor’s
Mine Safety and Health Administration require regular inspections at the nonfederal
dams within their jurisdiction. Even so, there are concerns that most state dam safety
programs have inadequate staff and funds to effectively inspect or monitor all of the
dams for which they are responsible. Further, there are concerns that states, local
governments, and other nonfederal dam owners may not have the financial resources
to maintain and rehabilitate their dams.
The collapse of the I-35W bridge in Minnesota highlighted the potential for
unexpected infrastructure failure. This may result in a review of the safety of other
elements of our nation’s inventory of critical infrastructure such as dams, levees,
tunnels, and bridges — and a call for additional funding to resolve any deficiencies.
Congress has periodically been urged to provide federal support for rehabilitation
work at nonfederal dams. Demand for such assistance is likely to increase, but
currently no federal policy describes the conditions under which federal funding is
appropriate, nor has Congress established criteria for prioritizing funding among
nonfederal projects.

Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Dam Failure Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Potential Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Likelihood of Failure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Managing Dam Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Federal Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
State Dam Safety Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Federal Support for State Dam Safety Programs . . . . . . . . . . . . . . . . . . 7
Reducing Dam Failures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Identifying Unsafe Dams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Inspections of Federal Dams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Inspection of Nonfederal Dams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Dam Rehabilitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Federal Dam Rehabilitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Department of Defense, Army Corps of Engineers . . . . . . . . . . . . . . . 11
U.S. Department of the Interior, Bureau of Reclamation . . . . . . . . . . 12
Rehabilitating Nonfederal Dams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
State Rehabilitation Funding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Federal Funding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
List of Figures
Figure 1. Dam Ownership . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Figure 2. Construction of Federal and Nonfederal Dams . . . . . . . . . . . . . . . . . . . 5
List of Tables
Table 1. Hazard Level: Description and Number . . . . . . . . . . . . . . . . . . . . . . . . . 4
Table 2. Agency-Owned Dams by Hazard Level and Frequency of
Formal Inspections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Table 3. State Grants for Dam Rehabilitation as of October 2003 . . . . . . . . . . . 13

Aging Infrastructure: Dam Safety
Introduction1
Dams provide broad economic and social benefits, including flood control,
hydroelectric power, recreation, navigation, and water supply for drinking, irrigation,
and industrial uses. Dams also entail financial costs (for construction and for
operation and maintenance) and sometimes environmental costs (e.g., loss of riverine
habitat). Dams also can present a risk to public safety, local and regional economies,
and the environment.
Prior to September 11, 2001, Congress had expressed an increasing interest over
several decades in dam safety. In recent years, congressional interest has focused
largely on securing and protecting U.S. dams and water storage facilities from terror
attacks. Hurricane Katrina and the disastrous failure of levees that once protected
New Orleans, however, have renewed congressional interest in the structural integrity
of major water infrastructure.
The modern period of congressional concern began in the 1970s with dam
failures that resulted in loss of life and billions of dollars in property losses.2
Congress and private groups interested in dam safety noted that, while states and
localities are responsible for the maintenance and safety of 95% of the nation’s dams,
large numbers of older dams lacked the maintenance needed to guarantee operational
integrity and prevent failure. These aging dams represented then — and continue to
present — a potential hazard to downstream populations.
A first essential task was to develop accurate data on the nation’s dams: their
number, type, structural condition, and other information useful for making decisions
about dam safety policy and priorities. This was achieved in 1972 with the creation
of the National Inventory of Dams (NID)3 — a computerized, periodically updated4
catalogue of U.S. dams, maintained by the U.S. Army Corps of Engineers, that
1 This report was originally written by Kyna Powers with assistance from Richard Sachs.
2 In 1972, failure of a mine tailings dam at Buffalo Creek, WV, flooded a 16-mile valley and
killed 125 people. In 1976, Teton Dam (ID) failed, causing $1 billion in property damage
and killing 11 people. Kelley Barnes Dam (GA) failed in 1977, killing 39 people and
causing an estimated $2.8 million in damage. More recently, the 2003 failure of the Silver
Lake Dam (MI) caused more than $100 million in damage, and the Kaloko Dam (HI) failed
in March 2006, killing 7 people.
3 The NID was first authorized in the National Dam Inspection Act of 1972 (P.L. 92-367)
and later consolidated under the Water Resources Development Act of 1996, National Dam
Safety Program Act (P.L. 104-303, Title II §215; 33 U.S.C. §467).
4 The NID was last updated in February 2005. See [http://crunch.tec.army.mil/nidpublic/
webpages/nid.cfm].

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presently lists over 79,000 public and private dams.5 For the purposes of the NID,
a dam is defined as “any artificial barrier that has the ability to impound water ... for
the purpose of storage or control of water” that (1) is greater than 25 feet in height
with a storage capacity of more than 15 acre-feet6 (af), (2) is greater than 6 feet in
height with a storage capacity of more than 50 af, or (3) poses a significant threat to
human life or property should it fail.
Federal and nonfederal dams in the NID were constructed for a variety of
purposes. By far, the greatest number of dams — more than 40% — were
constructed primarily for recreational purposes. Other purposes served by dams, in
descending order, include fire protection (20.0%), flood control (19.8%); irrigation
(11.8%); water supply (9.3%); fish and wildlife (4.2%); hydroelectric (2.8%); debris
control (2.0%); mining (tailings dams; 1.8%); and navigation (0.1%). Many dams
serve multiple purposes. For approximately 9.7% of the dams in the NID, the
purposes are unspecified.7
Over 56% of dams in the NID are privately owned. (See Figure 1.) Slightly
more than 20% are owned and operated by local governments. About 4.8 % of dams
are owned by states and 2.4% by public utility companies. The federal government
owns only 4.7% of all NID dams, but this small number (3,771) includes the dams
many Americans view as iconic: the great hydroelectric dams of the West, like Grand
Coulee and Hoover.8 The ownership of some NID dams is not indicated in the
database because that information was not reported to the Corps.
While the federal government owns less than 5% of NID dams, more than 30%
of all dams in the NID inventory were funded, designed, or constructed with federal
resources, most of them through the Department of Agriculture’s Natural Resources
Conservation Service (NRCS). NRCS’s involvement in dam construction stems
primarily from the Watershed Protection and Flood Prevention Act of 1954,9 which
authorized it to cooperate with states and local agencies to undertake works of
improvement for flood prevention and other purposes. Under this act and an earlier
law to build projects in 11 designated watersheds, NRCS has helped build more than
10,000 upstream flood control dams beginning in 1948. These are generally
relatively small dams owned by public or private entities other than the federal
government. These nonfederal entities are principally responsible for the dams’
operation, maintenance, and security.10
5 Other sources cite different figures; the online NID data is used throughout this report
unless otherwise specified. When appropriate, these data are referred to as NID Data.
6 One acre-foot of water is the amount of water that will cover an acre of land to a depth of
one foot, approximately 326,000 gallons.
7 NID Data.
8 U.S. Dept. of Homeland Security, Federal Emergency Management Agency, The National
Dam Safety Program Fiscal Years 2000-2001 (Washington, DC: December 2001), p. 6
(Hereafter, cited as FEMA report, 2000-2001).
9 P.L. 566 (83rd Cong.).
10 U.S. Dept. of Agriculture, Natural Resources Conservation Service, A Report to Congress
on Aging Watershed Infrastructure (Washington, DC: June, 2000), pp. 1-2. Hereafter cited
(continued...)

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Figure 1. Dam Ownership
Unknown/
Public Utility
Other
2.4%
State
11.5%
4.8%
Federal
4.7%
Local
20.1%
Private
56.4%
Excluding the NRCS, which does not administer any dams, nine federal
agencies operate, or regulate dam safety at approximately 8,500 sites (including non-
NID dams).11 Six federal agencies operate NID dams: the Department of Defense
(862), Department of the Interior (751), Department of Agriculture (326), Tennessee
Valley Authority (83), Department of Energy (16), and State Department (7). In
addition, three agencies regulate but do not operate NID dams: FERC regulates 1,775
hydropower dams; the Department of Labor’s Mine Safety and Health
Administration regulates 745 dams; and the Nuclear Regulatory Commission
regulates 11 dams. While dams administered by one agency are not generally
regulated by another agency, there are cases where private hydroelectric projects,
regulated by FERC, are located at federal dams.
Congressional interest in dam safety generally falls into three areas: (1) dam
security and the potential for acts of terrorism at major U.S. dam sites; (2) prevention
of potential dam failures due to structural deficiencies; and (3) recovery from dam
failures. This report focuses on the second category, because it is a topic that will
likely become more important as the nation’s dams age; further, it has gained
additional attention in the aftermath of Hurricane Katrina.
Dam Failure Risk
While dams have multiple benefits, their failure or misoperation could threaten
public safety, local and regional economies, and the environment. Risk has two
primary components: (1) the damage and deaths associated with dam failure or
misoperation, and (2) the likelihood of such a failure.
10 (...continued)
as NRCS Report, 2000.
11 FEMA Report, 2000-2001, p. 8-9. This figure differs from the NID-based data on dam
ownership shown in Table 2. Some of these dams may not qualify for inclusion in the NID.

CRS-4
Potential Damage
To quantify the potential harm associated with a dam’s failure, the Interagency
Committee on Dam Safety prepared a hazard potential classification system.12 As
described in Table 1, the three hazard ratings (low, significant, and high) do not
indicate the likelihood of failure, but reflect the amount and type of damage that a
failure would cause. Hazard ratings for each dam are included in the NID. From
2000 to 2006 the number of high-hazard dams increased from 9,921 to 11,811.
According to the Federal Emergency Management Agency (FEMA), development
below dams is the primary factor increasing dams’ hazard potential.13
Table 1. Hazard Level: Description and Number
Hazard Classification
Result of Failure or Misoperation
Number of Dams
High Hazard
— Loss of life is probable.
11,811
— Other economic or environmental loss
possible, but not necessary for this
classification.
Significant Hazard
— No probable loss of human life.
13,407
— Could result in economic loss,
environmental damage, and disruption of
lifeline facilities, etc.
Low Hazard
— No probable loss of human life.
54,349
— Few economic or environmental losses;
losses are generally limited to the owner.
Source: NID Data. The hazard level of 210 dams was not reported to the Corps for inclusion in the
NID.
Likelihood of Failure
While catastrophic dam failures are fairly infrequent, states reported 1,090 dam
safety incidents — including 125 failures — between 1999 and 2004.14 A number
of factors, including age, construction deficiencies, inadequate maintenance, and
seismic or weather events, contribute to the likelihood of dam failure. For example,
some failures are the direct result of flows larger than the dams were built to
withstand. With the exception of seismic or weather events, age is a leading
indicator of dam failure. In particular, the structural integrity and operational
effectiveness of dams may deteriorate with age, and some older dams may not
12 Interagency Committee on Dam Safety. Federal Guidelines on Dam Safety: Hazard
Potential Classification System for Dams (FEMA 333). (October 1998, reprinted January
2004).
13 U.S. Dept. Of Homeland Security, Federal Emergency Management Agency. Dam Safety
and Security in the United States: A Progress Report on the National Dam Safety Program
in FY 2002 and 2003 (FEMA 466), April 2004.
14 National Performance of Dams, Dam Incidents Statistics Calculator, at [http://npdp.
stanford.edu/index.html]. This database provides a low estimate of dam safety incidents,
since reporting is voluntary; few private or local dams are included.

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comply with current dam safety standards established in the 1970s.15 Overall, more
than 30% of all dams in the NID are at least 50 years old, the designed lifespan of
many dams, and more than 17,000 will cross this threshold over the next 10 years.
(See Figure 2.) According to the Association of State Dam Safety Officials, in 2003,
approximately 3,243 U.S. dams had deficiencies that left them more susceptible to
failure.16 In 2000, another report estimated that more than $30 billion will be needed
to repair and rehabilitate the nation’s aging dams.17
Figure 2. Construction of Federal
and Nonfederal Dams
20,000
d
e 18,000
16,000
ruct 14,000
12,000
50+ years old
10,000
8,000
6,000
4,000
Dams Const
2,000
# of
-
25
45
65
85
05
25
45
65
85
05
<1806
1816-
1836-
1856-
1876-
1896-
1916-
1936-
1956-
1976-
1996-
Year Completed
Managing Dam Safety
Following dam failures at Buffalo Creek (WV, 1972), Teton Dam (ID, 1976),
and Kelly Barnes Dam (GA, 1977), legislative and executive actions established a
program for monitoring the nation’s dams and set guidelines for dam safety at federal
facilities. Subsequent legislation promotes state dam safety programs and facilitates
rehabilitation activities at federal and some nonfederal dams.
15 Eugene P. Zeizel and Robert H. Dalton, “Aging of Dams and Urban Development Require
Major Dam Rehabilitation Efforts: A Growing Problem in Floodplain Management,”
presented at the Annual Conference of the Association of State Flood Plain Managers,
Charlotte, NC (June 3-8, 2001). This report indicated that 85% of all U.S. dams (not just
NID dams) will be more than 50 years old by 2020.
16 Association of State Dam Safety Officials, State by State Statistics on Dams and State
Safety Regulation , 2004. See [http://www.damsafety.org/documents/Word/2004Stats.doc].
In 2003, FEMA reported that there were more than 2,600 unsafe dams based on a report by
the American Society of Civil Engineers entitled The 2003 Progress Report for America’s
Infrastructure (September 4, 2003).
17 Raul F. Silva, “A Methodology and Estimate of the National Cost for Dam Safety
Rehabilitation,” presented at a conference of the Association of State Dam Safety Officials,
Providence, RI (September 27, 2000).

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Federal Management
Through legislative and executive actions, the federal government has become
involved in multiple areas of dam safety. First, in 1972, Congress passed the
National Dam Inspection Act (P.L. 92-367), which authorized the Corps to undertake
a program of national dam inspections and to establish the National Inventory of
Dams. Activities under this law provided the impetus for broad scale monitoring and
a centralized location for information on many of the nation’s dams.
In 1977, following the failure of Teton Dam and Kelly Barnes Dam, President
Jimmy Carter ordered a review of federal dam safety activities, and subsequently the
ad hoc Interagency Committee on Dam Safety released safety guidelines for dams
regulated by federal agencies.18 The Federal Guidelines for Dam Safety establish a
basic structure for agencies’ dam safety programs. In general, the guidelines
encourage federal agencies and dam owners regulated by federal agencies to abide
by uniform safety standards. They direct that each agency with dam safety
responsibilities have a dam safety officer and that the agencies coordinate with other
agencies. They also establish guidelines for staff training, periodic evaluations,
documenting dam safety activities, and operation and maintenance.
Congress also enacted the Reclamation Safety of Dams Act (P.L. 95-578, 43
U.S.C. §508) in 1978 to set more detailed guidelines for the Bureau of Reclamation.19
This act authorizes Reclamation to preserve the structural stability of its dams and
related facilities by performing modifications.
State Dam Safety Programs
States have primary responsibility for the safety of 95% of the nation’s dams.
According to the Association of State Dam Safety Officials, every state but Alabama
and Delaware20 has a dam safety regulatory program.21 Typically these programs
include “(1) safety evaluations of existing dams, (2) review of plans and
specifications for dam construction and major repair work, (3) periodic inspections
of construction work on new and existing dams, and (4) review and approval of
emergency action plans.”22 Many state dam safety programs are poorly funded. In
2004, state budgets for dam safety averaged $742,000,23 ranging from less than $50
18 Interagency Committee on Dam Safety and U. S. Dept. of Homeland Security, Federal
Emergency Management Agency, Federal Guidelines for Dam Safety (June 1979 reprinted
April 2004).
19 While the Bureau of Reclamation manages the most dams, the U.S. Army Corps of
Engineers manages the most NID dams.
20 Alabama has 1,403 dams and Delaware has 61 dams.
21 Association of State Dam Safety Officials, State by State Statistics on Dams and State
Safety Regulation — 2004.
22 Ibid.
23 Average of reported state budgets; excludes Delaware, Louisiana, Michigan, Nevada,
(continued...)

CRS-7
per state-regulated dam (IA, IN, KS, MS, OK and TX) to more than $16,000 per dam
regulated by Puerto Rico.24
Federal Support for State Dam Safety Programs. While federal
activities in the 1970s generally focused on increasing dam safety information and
strengthening requirements at the nation’s federal dams, subsequent legislation began
to address the safety of nonfederal dams. In 1996, Congress created the National
Dam Safety Program (NDSP)25 and assigned responsibility for administering it to
FEMA. The NDSP is the nation’s principal dam safety program; previously, there
was no comprehensive national effort devoted to nonfederal dam safety and the
safety of downstream populations.
Management of the NDSP. The NDSP is a mechanism for federal and state
cooperation that includes an Interagency Committee on Dam Safety (ICODS) with
the Director of FEMA as its chair. ICODS, which was initially formed in 1980, is
composed of representatives from FERC, the International Boundary Water
Commission, the Nuclear Regulatory Commission, the Tennessee Valley Authority,
and the Departments of Agriculture, Defense, Energy, the Interior, Labor, and
Homeland Security (FEMA). ICODS is responsible for coordinating information
exchange among federal dam safety agencies.26
The act also established a National Dam Safety Review Board (NDSRB)
consisting of five representatives appointed from federal agencies, five state dam
safety officials, and one representative from the U.S. Society on Dams. All the
representatives are appointed by the director of FEMA. This board advises the
FEMA director on dam safety issues, including the allocation of grants.27
Assistance to States. The National Dam Safety Act establishes two state
assistance programs with budget authorizations. These include the following:
! Training for State Inspectors. At the request of states, FEMA
provides technical training to dam safety inspectors.
! Assistance to State Dam Safety Programs. States working toward or
meeting minimal requirements are eligible for assistance grants. The
objective of these grants is to upgrade state programs using the
ASDSO Model State Dam Safety Program as a guide. The model
state dam safety program includes a recommendation that dams be
inspected at least every five years.
23 (...continued)
South Carolina, and South Dakota, which did not report their dam safety budgets.
Association of State Dam Safety Officials, State by State Statistics on Dams and State Safety
Regulation — 2004.
24 Ibid.
25 National Dam Safety Program Act, P.L. 104-303, Title II §215 (33 U.S.C. §467).
26 P.L. 107-310, ICODS’ authority is limited to coordination among federal entities only.
27 National Dam Safety Program Act, P.L. 104-303, Title II §215 (33 U.S.C. §467)

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Allocation of state assistance grants is determined by the NDSRB and the
director of FEMA. In FY2000 and FY2001, FEMA distributed $8 million to states
with existing dam safety programs to assist with buying equipment, conducting dam
inspections, and developing Emergency Action Plans (EAPs). This money is not
available for rehabilitation activities.
Reauthorization of the NDSP. The NDSP was reauthorized in 2002 as the
Dam Safety and Security Act of 2003 (P.L. 107-310, 43 U.S.C. §467). P.L. 107-310
made several changes to the existing program, including the addition of (1) a new
goal for the program that encompasses dam security; (2) a goal for states to obtain
authority to require owners to improve security; (3) a limitation on the authority of
ICODS to exchange information among federal entities only; (4) a clearer definition
of the role of the NDSRB in relation to the states, and encouragement to maintain an
effective national program to enhance dam safety and protect human life and
property; and (5) the addition of two new research components on (a) information
technology to store, query, and distribute dam safety data related to dam performance
(failures, large storm events, earthquakes, etc.), and (b) dam safety vulnerability
assessments and management of sensitive dam information.
P.L. 107-310 authorized the program for an additional four years and increased
the total authorized funding to $8.6 million annually through FY2006 with funds
available until expended. Specified funding authorizations include an increase for
research from $1.0 million to $1.5 million for each fiscal year. The program retains
the authorized levels for dam safety training at $500,000, and increases authorized
funding for staff from $400,000 to $600,000 for the same time period.
The enactment of P.L. 109-460 authorized an average of $9.96 million annually
for FY2007 through FY2011 for FEMA-administered research, dam safety training,
and maintaining the NID.
Reducing Dam Failures
As the nation’s dams age, they are likely to develop various deficiencies. For
example, dams’ foundations can show signs of seepage, cracking, and movement.
To prevent failure or misoperation, these deficiencies must be identified and
corrected.
Identifying Unsafe Dams
The first step toward rectifying dam-safety issues is to identify safety
deficiencies. Such deficiencies are often identified by engineers during informal
inspections, or during formal inspections conducted by senior engineers. Formal
inspections are generally conducted after major seismic or weather events, and on a
periodic basis. As described below, the frequency and type of periodic inspections
varies across agencies.
Inspections of Federal Dams. Each of the six federal agencies that operate
federal dams is responsible for maintaining dam safety by performing maintenance,

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inspections, and rehabilitation work. The Federal Guidelines for Dam Safety,
established in 1979 by President Carter, provide basic guidance for agencies’ dam
safety programs. Specifically, this document recommends that agencies formally
inspect each dam at least once every five years. As shown in Table 2, however, most
agencies under the Department of the Interior require more frequent inspections.
These inspections are typically funded through the agencies’ operations and
maintenance (O&M) budgets.
Table 2. Agency-Owned Dams by Hazard Level
and Frequency of Formal Inspections
Agency
Number of Dams by Hazard Level
Frequency of
Formal
Total
Significant High
Inspectionsa
Department of Agriculture
Forest Service
326
70
29
5 years
Department of Defense
Air Force
29
0
0
5 years
Army
191
24
30
5 years
Corps of Engineers
608
90
470
5 years
Navy
34
4
4
5 years
Department of the Interior
Bureau of Reclamation
435
24
343
3 years
Bureau of Indian Affairs
64
19
44
3 years
Bureau of Land Management
2
2
0
3 years
Fish and Wildlife Service
177
22
11
2.5 years
National Park Service
72
30
13
5 years
Department of State
International Boundary
7
1
5
5 years
Water Commission
Tennessee Valley Authority
83
15
63
5 years
Department of Energy
16
2
1
5 years
Source: NID Data.
a. Inspection frequency obtained from agency officials in Nov. 2004.
Inspection of Nonfederal Dams. Inspecting nonfederal dams is generally
a state responsibility, but the states are often poorly funded. According to the
Association of State Dam Safety Officials, 10 state regulators are needed for every
250 dams to do the job of carrying out their responsibilities.28 However, the average
number of dams per FTE is 395 and only two states (CA and FL) and one territory
(PR) have the recommended number of staff.29
28 Association of State Dam Safety Officials, Model State Dam Safety Program (1998).
29 Association of State Dam Safety Officials, State By State Statistics on Dams and State
Safety Regulation — 2004.

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Federal Involvement. While regulating nonfederal dams is generally a state
responsibility, the federal government has assumed regulatory authority over certain
nonfederal dams. As described below, two federal agencies — FERC and the
Department of Labor’s Mine Safety and Health Administration (MSHA) —
participate in inspections of certain private dams. In addition, the NRCS may
become involved with inspections at the dams it constructed.
Private Hydropower Dams. Under the 1920 Federal Power Act, FERC
(formerly the Federal Power Commission) regulates more than 2,500 nonfederal
hydropower dams.30 Pursuant to the Federal Guidelines on Dam Safety and FERC
Order 122,31 FERC’s regional engineers are to inspect each high-hazard dam annually
and outside consultants are to inspect these dams every five years. Low-hazard dams
are to be inspected every three years. The federal government recovers the costs of
these and FERC’s other activities from the hydropower industry. In general, FERC’s
dam safety program has received positive recognition.32
Private Mining Dams. Under the Mine Safety and Health Act,33 MSHA
regulates 745 private dams. Under these regulations, dams used for surface mining
are normally inspected every two years and those used for underground coal mines
are to be inspected every four years.34
NRCS-Constructed Flood Control Dams. Since 1948, the NRCS has
constructed more than 10,500 flood control dams. These dams were turned over to
local entities under contracts that stipulate the nonfederal responsibility for operation
and maintenance of the dams. Therefore, the dam owners are responsible for
conducting inspections pursuant to state regulations. As resources permit, however,
NRCS may use funding appropriated under the Small Watershed Rehabilitation Act35
to help dam owners assess specific structural or operational problems. In certain
situations, NRCS will conduct an inspection as part of this assessment process.
As amended by §2505 of the 2002 farm bill (P.L. 107-171),36 the Small
Watershed Rehabilitation Program is authorized to receive both mandatory funding
through the Commodity Credit Corporation and discretionary funding to be
authorized through agriculture appropriations each year. Mandatory funding amounts
were to start at $45 million in FY2003 and increase by $5 million each year through
30 FEMA Report, 2000-2001, pp. 8-9. Of these 1,775 are included in the NID (261
significant-hazard and 697 high-hazard dams).
31 FERC, Order 122, 46 Fed. Reg. 9036 (January 28, 1981), 18 C.F.R. §12.
32 U.S. Dept. of Energy, Office of the Inspector General, FERC Dam Safety Program,
DOE/IG 0486, (October 2000).
33 P.L. 91-173, as amended by P.L. 95-164 (30 U.S.C. §801). See [http://www.msha.gov/
REGS/ACT/ACTTC.HTM].
34 Discussion with Kelvin Wu, Chief, Mine Waste & Geotechnical Engineering Division,
Mine Safety and Health Administration, Washington, DC, on November 19, 2004.
35 §313 of the Grain Standards and Warehouse Improvement Act of 2000 (P.L. 106-472).
36 §2505 of the Farm Security and Rural Investment Act of 2002 (2002 Farm Bill).

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FY2007, while discretionary funding was authorized at $45 million in FY2003 and
was to grow by $10 million each year through FY2007. To date, congressional
appropriators have prohibited mandatory funding each year while providing a portion
of the discretionary funding that had been authorized. Actual appropriations were
$29.8 million in FY2003, $29.6 million in FY2004, $27.5 million in FY2005, and
$31.5 million in FY2006, $31.3 million in FY2007,37 and $19.9 million for FY2008.
The FY2009 budget estimate for this program is $5.9 million.38
Dam Rehabilitation
Federal Dam Rehabilitation
After dam safety deficiencies have been identified, rehabilitation activities
should be undertaken. However, most federal agencies do not have funding available
to immediately undertake all non-urgent repairs. Rather, they generally prioritize
their rehabilitation needs — based on various forms of risk assessment — and
schedule these activities in conjunction with the budget process. At some agencies,
dam rehabilitation needs must compete for funding with other construction projects.
Rehabilitation activities at the two major dam-owning agencies are described below.
Department of Defense, Army Corps of Engineers. At the Corps, most
dam deficiencies are addressed through the normal O&M procedures. However,
“rehabilitation or modification of Corps’ dams for safety purposes is accomplished
through the Major Rehabilitation Program and the Dam Safety Assurance
Program.”39 The purpose of 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 O&M program).” 40 This program does not apply to facilities that were
turned over to local interests for operation, maintenance, and major replacements
after they were constructed by the Corps. The Dam Safety Assurance Program,
however, applies to all dams built by the Corps regardless of current ownership.
Specifically, this program “provides for modification of completed Corps dam
projects which are potential safety hazards in light of current engineering standards
and criteria.... This program is intended to facilitate upgrading of those project
features which have design or construction deficiencies.”41 The Corps schedules
rehabilitation under all of these programs based on funding availability.
37 E-mail correspondence with Mr. Stuart Simpson, National Watersheds Program Leader,
U.S. Dept. of Agriculture, NRCS, Washington, DC (Oct. 30, 2007).
38 U.S. Dept. of Agriculture, 2009 Budget, Explanatory Notes for Committee on
Appropriations, vol. 2, pp. 18-36.
39 Army Corps of Engineers, Dam Safety Preparedness, EP1110-2-13 (June 1996), p. 5-1.
40 Ibid.
41 Ibid.

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U.S. Department of the Interior, Bureau of Reclamation. After
Reclamation’s engineers conduct dam safety inspections, through the Safety
Evaluation of Existing Dams (SEED) account, any corrective action is carried out
through the Initiate Safety of Dams Corrective Action program (ISCA).42 Authority
for Reclamation’s dam safety program originates in the Reclamation Safety of Dams
Act of 1978 (P.L. 95-578) and 1984 amendments (P.L. 98-404). Through ISCA
appropriations, Reclamation focuses funding on priority structures “based on an
evolving identification of risks and needs.” Prior to recent legislation, Reclamation
needed to submit a report to Congress for approval of modifications exceeding
$750,000. The 108th Congress increased that ceiling to $1,250,000.43 Costs incurred
due to “age and normal deterioration of the structure” are considered normal
operating costs and are cost-shared, with rates depending on the purposes for which
the structure was constructed (project purposes). Furthermore, “modifications
resulting from new hydrologic or seismic data or changes in the state of the art
criteria” are cost-shared, with 15% of the costs allocated for reimbursement
according to project purposes.
Rehabilitating Nonfederal Dams
In 2002, a task committee of the Association of State Dam Safety Officials
estimated that $36.2 billion was needed to rehabilitate nonfederal dams and that
$10.1 billion was needed by 2014 for repairs to “the nation’s most critical dams.”44
Responsibility to undertake this rehabilitation generally falls to dam owners.
State Rehabilitation Funding. While the federal government does provide
some direct funding for rehabilitating nonfederal dams, states and dam-owners bear
the brunt of the costs. Most states have little funding to repair their own dams, let
alone those dams owned by local governments, public utilities, and private entities.
According to the task committee of the Association of State Dam Safety Officials,
in 2003, nine states (AZ, MA, MD, NJ, NY, OH, PA, UT, and WI) have loan or grant
programs to repair unsafe dams. These programs generally focus on publicly owned
dams. Additional information on these programs is provided in the Task
Committee’s 2003 report and is recreated in Table 3.45
Federal Funding. While the federal government does help fund
improvements to state dam programs, little federal funding is available for
rehabilitating nonfederal dams. FEMA and NRCS are the primary sources of federal
support for nonfederal dam rehabilitation.
42 FY2009 Bureau of Reclamation Budget Justification, pp. BW-8 and 9.
43 A Bill to Authorize Additional Appropriations for the Reclamation Safety of Dams Act
of 1978, P.L. 108-439.
44 A Task Committee of the Association of State Dam Safety Officials, The Cost of
Rehabilitating our Nation’s Dams: A Methodology, Estimate, and Proposed Funding
Mechanisms (December 2002, revised October 2003), p. 4. See [http://www.damsafety
coalition.org/files/pdf/asdsoreport.pdf].
45 Ibid.

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Table 3. State Grants for Dam Rehabilitation as of October 2003
Source and
Program
Program
Loan/Grant
State
Amount of
Eligibility
Term of Loan
Type
Name
Amount
Funding
AZ
Loan or
Dam Repair
Legislature,
State engineer
Loan for the
Term of loan is
grant
lien fund,
determines dam
cost of the
up to 20 years at
inspection
to be dangerous
project, or
3-6% interest
fees, filing
to life, non-
grant for a
depending on
fees, principal
emergency
portion of
the length
and interest
project costs
from previous
loans
MD
Loan and
Maryland
State agency/
Counties,
planning
Environmental
non-profit
utilities and
assistance
Service
corporation
private groups.
Need to have
established
service district
for water
supply,
resource
reclamation,
dredging or
storm water
MA
Grants
Funding via
Local
75% of the
Dept. of
communities
project, local
Environmental
for repairs or
share can be
Management.
removal
in-kind
No new
contributions
appropriation
as of Oct.
2003.
NJ
Revolving
Dam
$20M-$5M
Local units of
Cost of
Up to 20 years
loan fund
Restoration
for state high
governments,
project for
at 2% assessed
and Clean
hazard dams,
private owners
loans
against real
New grant
Water Trust
$15M loans.
can be co-
Up to 100%
estate benefitted
fund for
Fund
In 2000 an
applicants
for grants
municipally
additional
owned dams
$9.5a was
added
NY
Grants
Clean
$17M bonding
Municipality
75% of
Water/Clean
for dam safety
eligible
Air Bond Act
projects
project (25%
local match)
$300,000 cap
per project
OH
Revolving
Ohio Water
Revolving
Owner must be
5-25 years at
loan fund
Development
loan fund
under mandate
lower than
Authority
from ODNR.
market rate
Dam Safety
Loan Program-
local units of
government,
state districts.
Dam Safety
Linked Deposit

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Source and
Program
Program
Loan/Grant
State
Amount of
Eligibility
Term of Loan
Type
Name
Amount
Funding
Program-
private
ownership/orgs.
PA
Revolving
Pennvest
Revolving
Projects
Up to cost of
20-30 years at
loan fund
loan fund, $2B
associated with
project
low interest
from state
wastewater,
general
water supply or
purpose funds
stormwater
UT
Loans or
Utah Board of
$4.5a from
High hazard
80-95% grant
grants
Water
general
dam owners.
for irrigation
Resources
revenue and
Mandated
or water
0.8 cent sales
repairs
supply dams,
tax (created
loans or
originally to
grants for
deal with
other owners
flood control
problems)
WI
Grants
DNR
$11.5M of
Local units of
50-50 grants
Municipal
bonding over
government and
up to a
Dam Grant
10 years.
Lake Districts
$200,000
Program
Currently fully
maximum
subscribed
Source: Association of State Dam Safety Officials. The Cost of Rehabilitating Our Nation’s Dams: A Methodology,
Estimate and Proposed Funding Mechanism Appendix B (Dec. 2002, revised Oct. 2003). See [http://www.
damsafetycoalition.org/files/pdf/asdsoreport.pdf].
a. Units not included in source table.
FEMA. As described above, the Department of Homeland Security, through
FEMA, runs the National Dam Safety Program which offers training and other
assistance to state dam safety programs, though it generally does not provide
rehabilitation funding. Legislation in the 109th Congress would have extended the
NDSP and authorized funding through FY2011 and would have provided a total of
$350 million to FEMA for a grant program for states to rehabilitate and repair
publicly owned dams. Authorized funding would have been $50 million for FY2007
and $100 million annually through FY2011. Through other programs, FEMA may
provide assistance to reduce the flood damage a failure would cause.46 However, this
assistance generally does not include funding for rebuilding or rehabilitating dams.
NRCS. Many upstream flood control dams were built with assistance from the
NRCS and turned over to local sponsors. Many of these dams are now nearing the
end of their design life and some have significant rehabilitation needs. The NRCS
has estimated that more than $540 million is needed to rehabilitate these dams.47 In
2000, Congress enacted legislation authorizing $90 million in discretionary funding
46 See FEMA’s Mitigation Grant Programs at [http://www.fema.gov/government/grant/
index.shtm].
47 NRCS Report, 2000, pp. 1, 15.

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over five years to rehabilitate aging flood-water retention projects.48 Funds are to be
allocated based on an annual ranking of requests for rehabilitation assistance. For
FY2002, Congress appropriated $10 million for this dam rehabilitation program.
For FY2003, the Administration did not include the program in its budget
request. However, the 2002 farm bill49 established the Small Watershed
Rehabilitation Program, and included $275 million in mandatory funding for the
program through FY2007. The Small Watershed Rehabilitation Program is
significant because it is the first federal initiative to dedicate funding assistance to
repair nonfederal dams (rather than tear down or build new dams). It uses a cost-
share formula providing for 65% federal-35% local funding. In the past, cost sharing
has been an equal responsibility of the federal government and local sponsors for
most purposes.
Other Agencies. In general, federal agencies such as the Corps and
Reclamation do not rehabilitate nonfederal dams. As described above, however, the
Corps does sometimes repair structural deficiencies that resulted from its
participation in the design or construction of the nonfederal dam. Though quite rare,
Congress has also directed federal agencies to use their dam safety appropriations to
rehabilitate a nonfederal dam that it did not help design or build.50 However,
representatives from the Corps and Reclamation have testified that they do not
support such congressional direction.51
Conclusions
As the nation’s dams age and development continues in floodplains, the
structural integrity of this infrastructure will become a more significant public safety
issue. In the aftermath of Hurricane Katrina, dams’ planned capacity to withstand
floods and other natural disasters has come under increased scrutiny. However, it is
unclear to what extent there will be a widespread re-evaluation of flood and
earthquake ratings at high-hazard dams. Such an evaluation could raise additional
policy questions. For example: (1) what criteria should be used to determine whether
current risks are acceptable; (2) if risks are not acceptable, should the dam be
improved, or should other activities (e.g., changes to the design and or placement of
downstream development) be undertaken; and (3) who should pay?

Regardless of whether dams were constructed to withstand an earthquake or
flood of “appropriate” magnitude, they may have age-related deficiencies that need
to be corrected to maintain current levels of safety. Therefore, it is likely that
48 The Grain Standards and Warehouse Improvements Act of 2000, P.L. 106-472, §313.
49 §2505 of the Farm Security and Rural Investment Act, P.L. 107-171.
50 See, for example, Goshen Dam (VA). Information from Charles Pearre, U.S. Army Corps
of Engineers, Washington, DC, on February 2, 2005.
51 U.S. Senate, Energy and Natural Resources Subcommittee on Water and Power,
Miscellaneous Water and Hydroelectric Project Bills, S.Hrg. 108-271 (108th Congress), p.
28.

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appropriations requests for safety inspections and rehabilitation activities will
continue and may increase. It should be noted, however, that there currently are no
clear criteria for prioritizing dam rehabilitation funding across agencies.
It is also unclear to what extent the federal government will fund inspection and
rehabilitation activities at nonfederal dams. Through the National Dam Safety
Program, the federal government provides training and assistance to state dam safety
programs; authorization of appropriations for this program was extended through
FY2011. Further, Congress has authorized appropriations for rehabilitation activities
at several nonfederal dams. While there is likely to be an increasing demand for such
assistance, there is currently no federal policy that describes the conditions under
which federal funding is appropriate, nor has Congress established criteria for
prioritizing funding among nonfederal projects.