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Updated February 23, 2017
Dam Safety: Federal Programs and Authorities
According to the National Inventory of Dams (NID), there
Figure 2. State-Regulated High-Hazard Dams
are more than 90,000 dams in the United States. Of these,
about 4% are owned and operated by the federal
government; the remaining 96% are owned by state and
local governments, public utilities, or private companies
(see Figure 1). Many of these dams were built more than
50 years ago. Recent events—including the evacuation of
thousands of people in California due to structural
deficiencies of the emergency spillway at Oroville Dam (a
state-owned dam)—have led to increased attention on the
condition of dams and the federal role in dam safety. This
document discusses the U.S. dam inventory, safety repair
estimates, federal dam safety efforts, and related issues for
Congress.
Figure 1. Dam Ownership in the United States
Source: CRS, using ASDSO and NID data.
What Is the Federal Role?
The federal dam safety approach can be divided into three
categories: (1) support for state dam safety efforts; (2)
support for federal dams; and (3) support for certain
nonfederal dams.
Support for State Dam Safety
U.S. states (except Alabama) regulate dam safety for
nonfederal dams. The owners of those dams are generally
Source: National Inventory of Dams, 2017.
responsible for investing in the safety, rehabilitation, and
repair of their dams; selected states provide a limited
Inventory and Repair Estimates
amount of assistance for these activities.
The NID, maintained by the Army Corps of Engineers
The main source of federal support is the National Dam
(Corps), catalogs information from 50 states, Puerto Rico,
and federal agencies on most of the nation’s substantial
Safety Program (NDSP), operated by the Federal
Emergency Management Agency (FEMA). NDSP’s
dams. Of the dams in the NID, about 17% (15,498) are
primary aim is support for state dam safety agencies. NDSP
classified as high hazard (i.e., the loss of at least one life is
activities include providing dam safety information
likely if the dam fails). The overall number of high-hazard
resources and training, facilitating information exchanges,
dams has increased in the past decade, as has the number of
and supporting state dam safety programs with grant
dams in need of repair. In 2015, the NID listed about 1,780
assistance. NDSP is supported by the National Dam Safety
state-regulated, high-hazard facilities with structural ratings
of “poor” or “unsatisfactory,” meaning they were in need of
Review Board. The board consists of federal and state
members, and it advises FEMA’s administrator on national
remediation (see Figure 2).
dam safety policy. Separately, the Interagency Committee
on Dam Safety—chaired by FEMA and consisting of
The Association of State Dam Safety Officials (ASDSO)
multiple federal agency members—serves as a forum for
estimates that state-regulated, high-hazard dams have repair
coordination of federal efforts to promote dam safety.
needs of approximately $18.7 billion (overall needs for
state-regulated dams are estimated at $60.7 billion). It is
Another federal agency involved in safety measures for
more difficult to track repair needs at nonfederal facilities
state and nonfederal dams is the Federal Energy Regulatory
with no reporting, and there is no comparable aggregate
Commission (FERC), which issues licenses and preliminary
reporting on federal dam safety repair needs.
permits for most nonfederal hydroelectric projects. These
projects often include a dam whereby FERC officials
review and inspect the dam regularly for safety reasons,
among other things. Additionally, FERC has a dam safety
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Dam Safety: Federal Programs and Authorities
program that oversees approximately 2,523 dams, with 805
New Authorities in the WIIN Act
classified as high hazard.
The Water Infrastructure Improvements for the Nation Act
(WIIN Act, P.L. 114-322), enacted in December 2016,
Support for Federal Dams
authorized new support for dam rehabilitation efforts:
The federal government has statutory responsibilities for
monitoring, upkeep, and repair of federally owned dams.
Section 5006 authorized a FEMA grant program for
The two main federal agencies that own dams are the Corps
rehabilitation of nonfederal, high-hazard dams. Grants
and the Bureau of Reclamation (Reclamation). Together,
under this section would go to states, with a cost share
these agencies own 34% of federal dams, including many
of 65% federal and 35% nonfederal. The bill authorized
large dams:
$10 million in appropriations for FY2017 and FY2018;
$25 million for FY2019; $40 million in FY2020; and
The Corps operates more than 700 dams, many
$60 million for FY2021-FY2026.
upstream of or near urbanized areas. Although many
Corps dams are designated as high hazard, no Corps
Section 1177 authorized the Corps to provide funding
dams are in danger of imminent failure. The Corps
for the rehabilitation of nonfederal, high-hazard dams
implements a dam safety program consisting of
constructed by the Corps prior to 1940 for flood control
inspections and risk analyses for all Corps dams that
purposes. Cost sharing under this section is 65% federal,
indicate the level of investment needed. In FY2016, the
35% nonfederal. The bill authorized $10 million per
Corps funded work on nine high-risk dams. In 2015, the
year in appropriations for FY2017-FY2026.
Corps estimated that its total dam repair needs were in
Section 3101 established a program and funding for the
excess of $24 billion.
repair of eligible projects at Bureau of Indian Affairs-
Reclamation owns 476 dams in the 17 states west of the
owned dams. For each year from FY2017 to FY2023,
Mississippi River, and 366 of these dams are classified
the bill authorized $10 million in appropriations for low-
as high hazard. Reclamation’s dam safety program
hazard dams and $22.75 million for high-hazard dams.
provides for an inspection program and authorizes
Section 1139 required the Corps to issue guidance
repairs to qualifying projects at Reclamation dams. In
clarifying certain federal dam safety project cost-sharing
FY2016, Reclamation funded five dam safety
responsibilities for nonfederal project sponsors.
construction projects.
The remaining dams are typically smaller dams owned by
Issues for Congress
other agencies, including land management agencies (e.g.,
Events such as the near-failure of the spillways at Lake
U.S. Fish and Wildlife Service), the Department of
Oroville have further highlighted the issues and risks
Defense, or the Bureau of Indian Affairs, among others. In
associated with dams near populated areas. Although the
overseeing these dams, federal agencies follow the Federal
federal role in dam rehabilitation and repair traditionally
Guidelines for Dam Safety published by FEMA.
has been focused on rehabilitation of federal facilities and
support for state dam safety programs, some have argued
Support for Safety Investments and Repair of
for an increased federal role in nonfederal dam safety and
Certain Nonfederal Dams
rehabilitation. In particular, Sections 5006 and 1177 of the
A limited set of publicly owned, nonfederal dams are
WIIN Act both authorized new support for nonfederal dam
eligible for federal support. For instance, the U.S.
repair and rehabilitation efforts that would be a departure
Department of Agriculture (USDA) has authority under the
from the traditional federal role. The extent to which these
Watershed Rehabilitation Program (P.L. 106-472, as
authorities are funded remains to be seen.
amended) to provide financial and technical assistance for
planning, design, and implementation of dam rehabilitation
Arguments for an increased federal role in nonfederal
projects (including upgrading or removal). Eligible dams
facilities may stem from one-time federal investment and/or
must have been built using selected USDA funds and must
licensing of these facilities and from the fact that states and
now pose a public health or safety concern. The program
facility owners may not be able to afford the dam safety
covers up to 65% of the total rehabilitation cost. Since the
costs on their own. Finally, many point to the potential for
program was first authorized in 2000, Congress has
the loss of lives and large federal outlays in emergency
appropriated more than $700 million for these rehabilitation
spending that might be necessary if a dam failure were to
projects.
occur. At the same time, safety and other reinvestment
needs at aging federal facilities continue to be significant,
The Corps Rehabilitation and Inspection Program (RIP, or
and some call for increased funding to remediate these
the P.L. 84-99 program, a program used mainly for levees)
problems. How (or if) some or all these needs might be
also provides federal support for a few nonfederal dams that
addressed within a broader infrastructure investment effort
meet certain criteria (e.g., storage capacity for a 200-year
is an additional question that the 115th Congress may
flood event). RIP may provide assistance to flood control
consider.
works if the facility is flood damaged. As part of RIP, the
Charles V. Stern, Specialist in Natural Resources Policy
Corps periodically inspects participating facilities to ensure
Nicole T. Carter, Acting Section Research Manager
their owners are meeting the Corps’ maintenance standards.
Megan Stubbs, Specialist in Agricultural Conservation and
Because annual appropriations for the RIP program are
Natural Resources Policy
limited, major repairs under this authority sometimes are
provided through supplemental appropriations acts.
Kelsi Bracmort, Specialist in Agricultural Conservation
and Natural Resources Policy
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Dam Safety: Federal Programs and Authorities
IF10606
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