Drought in the United States: Science, Policy,
September 16, 2021
and Selected Federal Authorities
Charles V. Stern,
Drought―a deficiency of moisture that results in adverse effects―occurs to some extent almost
Coordinator
every year in areas of the United States. Droughts can simultaneously reduce available water
Specialist in Natural
supplies and increase demands for water. Drought has the potential to affect economic and
Resources Policy
environmental conditions on local, regional, and national scales, as well as to cause disruptions in

water supplies for households and communities.
Eva Lipiec, Coordinator
Analyst in Natural
Droughts are a component of climate variability and may be seasonal, multiyear, or multi-decadal
Resources Policy
in duration. According to an August 2021 Intergovernmental Panel on Climate Change (IPCC)

report on the physical science of climate change, variable precipitation and rising temperatures
are intensifying droughts in some U.S. regions. According to the report, certain types of droughts,
Lisa S. Benson
such as those causing agricultural impacts, are expected to be more likely in the western and
Analyst in Agricultural
Policy
central regions of the United States in the future.

The federal government generally defers to state primacy in surface and groundwater allocation,
Nicole T. Carter
and states and local entities typically lead efforts to prepare for drought. Multiple federal
Specialist in Natural
agencies contribute to these efforts to predict, plan for, and respond to drought. The federal
Resources Policy
government, and in particular the National Oceanic and Atmospheric Administration (NOAA),

plays a key role in researching and monitoring drought through the National Integrated Drought
Elena H. Humphreys
Information System (NIDIS) and the U.S. Drought Monitor. Other federal agencies, such as the
Analyst in Environmental
U.S. Department of Agriculture (USDA) and the U.S. Geological Survey (USGS), also research
Policy
and monitor drought factors and conditions. The USDA provides the primary federal financial

aid to lessen the impacts of drought and compensate for agricultural production loss after drought
onset.
Pervaze A. Sheikh
Specialist in Natural
Resources Policy
Congress has authorized federal assistance for other aspects of drought, but these programs

generally are limited in scope. In localities or watersheds with major projects managed by the
U.S. Bureau of Reclamation (Reclamation, which operates exclusively in the 17 arid western
Megan Stubbs
states) and the U.S. Army Corps of Engineers (USACE, which operates nationwide), the federal
Specialist in Agricultural
role in water management is more direct and can be especially controversial during times of
Conservation and Natural
drought, when multiple users compete for water. Congress has directed both Reclamation and
Resources Policy
USACE to plan for future droughts at federally authorized projects. Other federal programs, such

as those supporting nonfederal efforts to develop water conservation, water reuse and recycling,
rural water supplies, or other municipal and industrial water supplies, may prioritize projects that

lessen the impacts of drought even when these programs do not focus exclusively on drought.
Severe drought in California from 2012 to 2016, as well as widespread drought in the western United States in 2021 and
other recent events, has raised the profile of drought and led to increasing congressional and administrative proposals to
prepare for and respond to its impacts. Congressional interest in drought may include new and amended authorities for
drought planning and response; emergency appropriations to alleviate drought impacts and enhance related activities; and
oversight of ongoing federal drought science, preparedness, and management efforts.

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Contacts
Author Information ........................................................................................................................ 38

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Introduction
Drought―a deficiency of moisture that results in adverse impacts―occurs to some extent almost
every year in areas of the United States. Drought has the potential to create economic and
environmental impacts on local, regional, and national scales, as well as disruptions in water
supplies for households and communities. For example, the National Oceanic and Atmospheric
Administration (NOAA) estimates the United States has experienced 29 billion-dollar drought
events since 1980, at an estimated total cost of over $267.9 billion.1 Although droughts are a
component of climate variability and may be seasonal, multiyear, or multi-decadal in duration,
variable precipitation and rising temperatures are intensifying droughts in some regions.2 Severe
droughts in California from 2012 to 2016, as well as widespread drought in the western United
States in 2021, have raised the profile of drought and led to increasing congressional and
administrative proposals to prepare for and respond to its impacts.
Multiple federal agencies contribute to efforts to predict, plan for, and respond to drought. NOAA
plays a key role in monitoring drought through the National Integrated Drought Information
System (NIDIS) and the U.S. Drought Monitor (through a partnership with the University of
Nebraska–Lincoln and the U.S. Department of Agriculture [USDA]). USDA provides the primary
federal financial aid to lessen drought’s impacts and compensate for agricultural production loss
after its onset. Federal water resource agencies such as the U.S. Bureau of Reclamation
(Reclamation) and the U.S. Army Corps of Engineers (USACE) face difficult tradeoffs in
operating federal water projects during drought; both agencies also have authorities and conduct
activities to mitigate drought impacts. Various other federal agencies and emergency authorities
also play a role in drought response and mitigation, including the U.S. Environmental Protection
Agency (EPA).
This report provides an overview of drought in the United States, including information on
drought science, monitoring, and forecasts and on drought types and intensity classifications. It
also discusses federal authorities related to drought planning and response, with a focus on
selected water-related agricultural, environmental, and natural resource-related authorities with
explicit ties to drought. It does not discuss broader disaster-related authorities and their potential
nexus to drought, such as the programs and authorities of the Federal Emergency Management
Agency (FEMA) and interactions between drought and other hazards and concerns (e.g., wildfire,
dust, and public health).
Overview of Drought in the United States3
The following sections provide information about drought in the United States, including a
discussion of the different causes of drought, potential linkages between drought and climate
change now and in the future, and how the impacts of drought are classified and forecasted in the
United States.

1 Costs represent the 2021 Consumer Price Index cost adjusted value if different from original value. National Oceanic
and Atmospheric Administration (NOAA), National Centers for Environmental Information, “Billion-Dollar Weather
and Climate Disasters: Events,” at https://www.ncdc.noaa.gov/billions/events/US/1980-2021.
2 For more information, see “Drought and Climate Change.”
3 For more information, contact Eva Lipiec, Analyst in Natural Resources Policy, or Nicole Carter, Specialist in Natural
Resources Policy.
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What Is Drought?
Droughts are a component of climate variability and may be seasonal, multiyear, or multi-decadal
(sometimes called megadroughts) in duration. Drought may be defined in various ways; NOAA,
for instance, defines it as “a deficiency of moisture that results in adverse impacts on people,
animals, or vegetation over a sizeable area.”4 Although a lack of precipitation is often central to
drought, high temperatures, high winds, lack of clouds, and low humidity also can contribute.5
Experts categorize definitions into four basic approaches to measuring drought: meteorological,
hydrological, agricultural, and socioeconomic.6 However, no one definition applies to all
circumstances.
 Meteorological drought typically is defined based on the degree of dryness in
comparison to some “normal” or average amount and the duration of a dry
period. Meteorological drought is region-specific, because atmospheric
conditions creating precipitation deficiencies vary from region to region.
 Hydrological drought is defined by the effects that periods of shortfalls in
precipitation (including snowfall) have on surface and subsurface water supply,
such as streamflows, reservoir and lake levels, and groundwater. The frequency
and severity of this type of drought are measured on a watershed or river basin
scale.
 Agricultural drought links characteristics of meteorological or hydrological
drought to agricultural impacts, with a focus on precipitation shortfalls,
evapotranspiration differences,7 soil moisture deficits, reduced groundwater or
reservoir levels, and other effects. The timing and severity of drought conditions
and the types of plants involved may yield different agricultural impacts. Some
experts use the term agricultural and ecological drought to capture not only the
agricultural effects but also the ecological effects of drought, such as plant water
stress that contributes to tree mortality.
 Socioeconomic drought associates the “supply and demand of some economic
goods with elements of meteorological, hydrological, and agricultural drought.”8
A socioeconomic drought may occur when the demand for an economic good,
such as water, food grains, fish, or hydroelectric power, exceeds supply due to a
shortfall in water supply.
Scientists also have been studying a phenomenon referred to as hot drought. In contrast to
precipitation-driven droughts, hot droughts are a result of high air temperatures, as warmer air
absorbs more water than cooler air.9

4 Drought.gov, “Defining Drought,” at https://www.drought.gov/what-is-drought/drought-basics#defining-drought.
5 For more information, see U.S. Geological Survey (USGS), “Drought: Things to Know,” at https://www.usgs.gov/
special-topic/water-science-school/science/droughts-things-know?.
6 National Drought Mitigation Center (NDMC), “Types of Drought,” at https://drought.unl.edu/Education/DroughtIn-
depth/TypesofDrought.aspx.
7 Evapotranspiration may be defined as the loss of water from a land area through transpiration from plants and
evaporation from the soil and surface water bodies such as lakes, ponds, and man-made reservoirs. For more about
evapotranspiration, see USGS, “Evapotranspiration and the Water Cycle,” at https://www.usgs.gov/special-topic/water-
science-school/science/evapotranspiration-and-water-cycle?qt-science_center_objects=0.
8 NDMC, “Types of Drought,” at https://drought.unl.edu/Education/DroughtIn-depth/TypesofDrought.aspx.
9 NOAA, Climate.gov, “Beyond 2016: Year in Review,” January 4, 2017, at https://www.climate.gov/news-features/
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Additionally, experts have begun to characterize drought by how quickly drought conditions
begin, with some scientists using the term flash drought to identify rapid-onset drought
conditions. Scientists at NOAA define a flash drought as “a drought event with greater than or
equal to two categories degradation in a four-week period based on the U.S. Drought Monitor.”
(For more about the U.S. Drought Monitor and its categories, see “Drought Classification.”)10
Flash drought is usually caused by anomalously high temperatures, winds, and/or radiation from
the sun rather than by precipitation deficits.11
Higher demand for water for human activities and vegetation in areas of limited water supply
increases the severity of certain types of drought. For example, drought during the growing
season likely is often considered more severe—in terms of impacts—than similar conditions
when cropland lies dormant. For policy purposes, drought often becomes an issue when it results
in a water supply deficiency. The effects of a water supply deficiency manifest in various ways,
including the following:
 Decreased precipitation and/or soil moisture affecting runoff and water
availability
 Low reservoir levels reducing allocations for multiple purposes (including
irrigation, navigation, energy production, recreation, fish and wildlife needs, and
other water supplies)
 Low stream flows limiting withdrawals for multiple purposes, including
municipal and industrial supplies
 Decreased inflow into and evaporation off of lakes (less exchange of water in a
lake can contribute to water quality problems and may hamper recreation)
Drought also can relate and contribute to other phenomena, such as wildfires and heat waves.12
Scientific advances, such as improved observation and understanding of atmospheric variability
and of North American precipitation and temperature variations, have enhanced understanding of
drought and the forces that contribute to it, although debates remain on those forces’ relative
importance. Drought likely never results from a single cause; rather, drought at a specific location
may be influenced by a mix of various interacting atmospheric anomalies, land-atmosphere
feedbacks, topographic features, and human activity, such as water use, among other forces and
factors. Regarding the role of atmospheric patterns and conditions, prolonged droughts typically

blogs/beyond-data/beyond-2016-year-review; and Bradley Udall and Jonathan Overpeck, “The Twenty-First Century
Colorado River Hot Drought and Implications for the Future,” Water Resources Research, vol. 53, no. 3 (February 17,
2017), pp. 2404-2416.
10 L. Gwen Chen et al., “Flash Drought Characteristics Based on U.S. Drought Monitor,” Atmosphere, Special Issue:
Meteorological and Hydrological Droughts, vol. 10, no. 9 (2019), pp. 498-513. Hereinafter, Chen et al., “Flash
Drought,” 2019. However, a recent expert literature review noted the absence of a universally accepted definition or
criteria for flash drought, with defined rates of onset for flash drought ranging between five days and eight weeks. See
Joel Lisonbee et al., “Making Sense of Flash Drought Definitions, Indicators, and Where We Go from Here,” Journal
of Applied and Service Climatology, vol. 2021, no. 1 (2021), pp. 1-19. For a description of the evolution of a flash
drought, see NOAA, “Flash Drought Engulfs the U.S. Southeast in September 2019,” October 9, 2019, at
https://www.climate.gov/news-features/event-tracker/flash-drought-engulfs-us-southeast-september-2019.
11 Chen et al., “Flash Drought,” 2019.
12 For more on wildfire, see CRS In Focus IF10732, Federal Assistance for Wildfire Response and Recovery, by Katie
Hoover, and CRS Report R43429, Federal Lands and Related Resources: Overview and Selected Issues for the 117th
Congress, coordinated by Katie Hoover. For more information about the potential relationship between droughts and
heat waves, see, for example, Linyin Cheng et al., “Physical Understanding of Human-Induced Changes in U.S. Hot
Droughts Using Equilibrium Climate Simulations,” Journal of Climate, vol. 32, no. 14 (July 15, 2019), pp. 4431-4443.
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occur when certain spatially and temporally large-scale anomalies in atmospheric circulation
patterns persist. These anomalies are referred to as teleconnection patterns and typically can last
several weeks to several months or can be prominent for several consecutive years.13 Ocean
conditions contribute to some teleconnection patterns, including the El Niño-Southern Oscillation
(ENSO) and the Pacific Decadal Oscillation (PDO).14 A relationship between tropical Pacific
Ocean conditions and drought in the United States is becoming better established. (For more on
the role Pacific Ocean conditions play in droughts in the United States, see text box “Droughts
and the El Niño-Southern Oscillation.”) Other atmospheric conditions, such as blocking ridges,
also may contribute to drought conditions.15
Droughts and the El Niño-Southern Oscillation
The El Niño-Southern Oscillation (ENSO) is an anomaly associated with central and eastern tropical Pacific Ocean
conditions―particularly sea surface temperatures (SSTs) and air pressure―that can affect the path of the jet
stream over mid-latitude North America and other regions globally, thereby influencing regional temperatures and
precipitation. ENSO conditions often are described by phase: El Niño, neutral, or La Niña. The La Niña phase
refers to the cooler-than-average SSTs in the central tropical Pacific region in the oscillating warming and cooling
pattern of ENSO. Scientists have increasingly linked drought in portions of the United States to SST anomalies in
the Pacific Ocean. La Niña’s influence on drought varies across the continent and may vary seasonally.

La Niña conditions can correlate with drier-than-normal winter conditions in California and the southwestern
United States, while also contributing to wetter-than-normal conditions in other regions of the United States.
ENSO’s impact on southwestern summer weather and precipitation is less clear.

In the southeastern United States, La Niña appears to be a contributor to some droughts (e.g., there seems
to be a weak link between La Niña and dry winter conditions), with multiple other factors also corresponding
or contributing to droughts in the region.

The effects of El Niño and La Niña on drought conditions on Hawaii and the insular areas of the Pacific vary
within the region.

In many regions of the country, ENSO forces play an unclear role and combine with multiple other factors,
such as topography, to determine conditions that could lead to drought (e.g., the effect of the Rocky
Mountains in Colorado).

Widespread flash droughts over the United States are often associated with La Niña conditions.
Sources: National Oceanic and Atmospheric Administration, National Ocean Service, “What Are El Niño
and La Niña?,” at https://oceanservice.noaa.gov/facts/ninonina.html; National Integrated Drought Information
System, “Western Drought Webinar,” July 20, 2021, PowerPoint presentation, at https://www.drought.gov/

13 For more about teleconnection patterns, see NOAA, National Weather Service Climate Prediction Center,
“Teleconnection Introduction,” at https://www.cpc.ncep.noaa.gov/data/teledoc/teleintro.shtml. According to NOAA, a
teleconnection pattern refers to a recurring and persistent large-scale pattern of pressure and circulation anomalies that
spans vast geographical areas. Many teleconnection patterns are planetary-scale in nature spanning entire ocean basins
and continents. Teleconnection patterns reflect large-scale changes in the atmospheric wave and jet stream patterns, and
they influence temperature, rainfall, storm tracks, and jet stream location and intensity over vast areas.
14 El Niño-Southern Oscillation (ENSO) is a periodic fluctuation in sea surface temperature (El Niño) and the air
pressure of the overlying atmosphere (Southern Oscillation) across the equatorial Pacific Ocean (NOAA, “El
Niño/Southern Oscillation (ENSO) Technical Discussion,” at https://www.ncdc.noaa.gov/teleconnections/enso/enso-
tech.php, and National Integrated Drought Information System (NIDIS), “Western Drought Webinar,” July 20, 2021,
PowerPoint presentation, at https://www.drought.gov/webinars/western-drought-webinar-july-20-2021). For more
about ENSO, see National Drought Mitigation Center, “ENSO and Drought Forecasting,” at https://drought.unl.edu/
Education/DroughtIn-depth/ENSO.aspx. For more information about the Pacific Decadal Oscillation, see Climate.gov,
“Going out for ice cream: a first date with the Pacific Decadal Oscillation,” August 25, 2016, at
https://www.climate.gov/news-features/blogs/enso/going-out-ice-cream-first-date-pacific-decadal-oscillation.
15 Blocking ridges are regions of high atmospheric pressure that disrupt typical wind patterns in the atmosphere.
Scientists identified a persistent ridge pattern, often referred to as the Ridiculously Resilient Ridge, contributing to
California’s 2012-2016 drought by diverting winter storms northward, thereby preventing them from reaching
California. For more information see, for example, Haiyan Teng and Grant Branstator, “Causes of Extreme Ridges That
Induce California Droughts,” Journal of Climate, vol. 30, no. 4 (February 15, 2017), pp. 1477-1492.
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webinars/western-drought-webinar-july-20-2021; Climate Assessment for the Southwest, “How Does ENSO
Affect SW Weather Patterns?,” at https://climas.arizona.edu/content/how-does-enso-affect-sw-weather-
patterns; Richard Seager et al., “Drought in the Southeastern United States: The Recent Drought in the
Context of a Millennium of Climate Variability, Physical Causes and Future Hydroclimate Change,” July 2008,
at http://ocp.ldeo.columbia.edu/res/div/ocp/drought/SE.shtml; A. Park Williams et al., “The 2016 Southeastern
U.S. Drought: An Extreme Departure from Centennial Wetting and Cooling,” Journal of Geophysical Research:
Atmospheres, vol. 122, no. 20 (2017), pp. 10888-10905; Colorado State University, Colorado Climate Center,
“ENSO and Colorado,” at https://climate.colostate.edu/co_enso.html; and L. Gwen Chen et al., “Flash
Drought Characteristics Based on U.S. Drought Monitor,” Atmosphere, Special Issue: Meteorological and
Hydrological Droughts, vol. 10, no. 9 (2019), pp. 498-513.
Notes: Some researchers associated the 2019 southeastern drought to a waning El Niño and other
phenomena, specifically the Indian Ocean dipole and Rossby waves (see Siegfried D. Schubert et al., “On the
Development and Demise of the Fall 2019 Southeast U.S. Flash Drought: Links to an Extreme Positive IOD,”
Journal of Climate, vol. 34, no. 5 (March 1, 2021), pp. 1701-1723);
For more on the ENSO effects on Hawaii and Pacific insular islands, see U.S. Global Climate Research Group
(USGCRP), “Hawai‘i and U.S.-Affiliated Pacific Islands” in Impacts, Risks, and Adaptation in the United States:
Fourth National Climate Assessment, vol. II, 2018, p. 1251; or Benjamin I. Cook et al., “Pan-Continental
Droughts in North America over the Last Millennium,” Journal of Climate, vol. 27, no. 1 (January 1, 2014), pp.
383-397.
Drought and Climate Change
The relationship between climate change and drought is complex, and the scientific
understanding of this relationship is evolving. The U.S. Global Change Research Program
(USGCRP), an entity composed of U.S. federal agencies, released its special report on the state of
climate science in 2017 and its periodic national climate assessment in 2018. In these reports, the
USGCRP made various observations related to drought, including the following:
 Variable precipitation and rising temperature were intensifying droughts, with
groundwater depletion (from withdrawal for human uses exceeding aquifer
recharge) further exacerbating drought risk.16
 Annual trends toward earlier spring snowmelt and reduced snowpack were
affecting water resources in the western United States, and those trends were
expected to continue.17
 Future droughts in most regions of the United States likely would be more
intense and could last longer due to projected decreases in soil moisture, with
trends likely strongest in the Southwest and the southern Great Plains.18
 The then-recent droughts and heat waves (as of 2017) had reached record
intensity in some U.S. regions but had not reached the geographical scale and
duration of the Dust Bowl era of the 1930s.19

16 USGCRP, “Water,” in Impacts, Risks, and Adaptation in the United States: Fourth National Climate Assessment,
vol. II, 2018, p. 2.
17 USGCRP, “Executive Summary,” in Climate Science Special Report: Fourth National Climate Assessment, vol. I,
2017, p. 11.
18 USGCRP, “Our Changing Climate,” in Impacts, Risks, and Adaptation in the United States: Fourth National Climate
Assessment, vol. II, 2018, p. 91.
19 USGCRP, “Executive Summary,” in Climate Science Special Report: Fourth National Climate Assessment, vol. I,
2017, p. 21.
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Regarding teleconnections patterns that may contribute to drought, a 2019 Intergovernmental
Panel on Climate Change (IPCC) report on climate change and land had low confidence in how
large-scale systems, such as ENSO, would respond to a warming climate and therefore how those
changes might affect the frequency and severity of drought.20 In August 2021, the IPCC released
its sixth assessment on the underlying physical science of climate change. The report provided
observations by drought type and region, and it synthesized projections regarding future drought
risk. For more on the drought discussion in the August 2021 IPCC physical science report, see
text box “Overview of the IPCC August 2021 Findings on U.S. Drought.”21
The August 2021 IPCC report identified research that projected an intensified rainfall response
over the equatorial Pacific Ocean as a result of ENSO-related sea surface temperature changes
under a warming climate, with resulting impacts over land.22 For a discussion of how ENSO’s La
Niña conditions can contribute to drier conditions and droughts in the continental United States,
see text box “Droughts and the El Niño-Southern Oscillation.”
Overview of the IPCC August 2021 Findings on U.S. Drought
The August 2021 Intergovernmental Panel on Climate Change (IPCC) physical science report provided the
following observations by drought type and U.S. region:

Meteorological Drought. For observed meteorological droughts, the report identified inconsistent trends
or mixed signals for both western and eastern North America (low confidence) and a decrease in the
duration and frequency of meteorological droughts in central North America (medium confidence).

Hydrologic Drought. For observed hydrologic droughts, the report identified mixed signals for trends for
western and central North America and limited evidence available for eastern North America.

Agricultural and Ecological Drought. The report identified an observed increase in agricultural and
ecological drought for western North America (medium confidence), inconsistent trends for central North
America, and inconsistent trends depending on metrics used and geographic areas for eastern North
America.
Among the changes in projected future droughts, the August 2021 IPCC physical science report identified the
following:

For western North America, limited evidence or inconsistent trends at +1.5 °C for all drought types and
increased hydrologic drought as well as agricultural and ecological drought at +2 °C warming (medium
confidence), with limited evidence and inconsistent trends for meteorological drought at those projected
temperature increases

20 Intergovernmental Panel on Climate Change (IPCC), “Land-Climate Interactions,” in Special Report on Climate
Change and Land, 2019, p. 146. According to IPCC, author teams evaluated their confidence about the validity of a
finding, providing a synthesis of the evaluation of evidence and agreement (levels of confidence include five qualifiers:
very low, low, medium, high, and very high; Virginia R. Burkett et al., “Point of Departure,” in Climate Change 2014:
Impacts, Adaptation, and Vulnerability. Part A: Global and Sectoral Aspects. Contributions of Working Group II to the
Fifth Assessment Report of the Intergovernmental Panel on Climate Change, 2014, p. 9).
21 IPCC, “Chapter 11: Weather and Climate Extreme Events in a Changing Climate,” in Climate Change 2021: The
Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental
Panel on Climate Change (in press), version date August 2021, Table 11.21, pp. 11-229 to 11-231 (hereinafter, report
cited as IPCC, AR6 Physical Science Basis; the August 2021 chapters in this report remain subject to revision). The
data were too limited to assess observed agricultural and ecological drought changes for small Pacific islands; Chapter
11 did not include information on extremes for these islands. For a depiction of the areas included in the western,
central, and eastern North America designations, see IPCC, “Chapter 1: Framing, Context, and Methods,” in AR6
Physical Science Basis, p. 1-197.
22 IPCC, “Chapter 11: Weather and Climate Extreme Events in a Changing Climate,” in AR6 Physical Science Basis,
pp. 11-17 and 11-110. The report did not identify a robust consensus in the research literature regarding changes in
amplitude of ENSO-related sea surface temperature variability (e.g., an intensification of how much warmer or cooler
than normal the surface ocean is along the equator in the central-to-eastern Pacific for El Niño and La Niña,
respectively).
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
For central North America, increased agricultural and ecological drought severity or frequency at both +1.5
°C and +2 °C warming (medium confidence)

For eastern North America, limited evidence or inconsistent trends at both +1.5 °C and +2 °C warming for
the various drought types
Source: IPCC, “Chapter 11: Weather and Climate Extreme Events in a Changing Climate,” in Climate
Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report
of the Intergovernmental Panel on Climate Change (in press), version date August 2021, Table 11.21, pp. 11-
229 to 11-231.
Some researchers have undertaken efforts to measure the contribution of human induced-
warming to specific U.S. droughts (known as attribution science).23 Efforts to link observed
droughts to human contributions to climate change, as well as to identify drought
nonstationarity,24 are complicated by the multiple factors that can influence the severity,
frequency, and duration or timing of a drought; by limitations on data availability, given there are
often fewer drought events to compare over time relative to other types of weather events; and by
challenges in identifying drought onset and termination.25
Drought Classification
Certain measures, or drought indicators, are typically used to assess and classify the intensity and
type of drought. Local, state, and federal entities may have different ways to classify drought,
which may depend on a single indicator or on several indicators, often combined with expert
opinion from the academic, public, and private sectors.
The U.S. Drought Monitor, a partnership between federal and nonfederal entities, uses multiple
indicators and indexes, together with expert opinion and stakeholder information, to estimate the
intensity and effects of ongoing drought conditions (Figure 1).26 According to NOAA, roughly
40-50 unique indicators are used to create the U.S. Drought Monitor map but not all geographic
areas are represented equally by the indicators.27 The U.S. Drought Monitor intensity scheme—

23 For example, see A. Park Williams et al., “Large Contribution from Anthropogenic Warming to an Emerging North
American Megadrought,” Science, vol. 368, no. 6488 (April 17, 2020), pp. 341-318 and Andrew Hoell et al., Drought
Assessment Report: The Causes, Predictability, and Historical Context of the 2017 U.S. Northern Great Plains
Drought, February 2019, NOAA, Earth System Research Laboratory, and University of Colorado, Cooperative Institute
for Research in Environmental Sciences, at https://www.drought.gov/sites/default/files/2020-09/2017-NGP-drought-
assessment.pdf. Using research like the former articles, the IPCC AR6 Physical Science Basis indicated medium
confidence in western North America’s observed agricultural and ecological drought having a human contribution
(IPCC, “Chapter 11: Weather and Climate Extreme Events in a Changing Climate,” in AR6 Physical Science Basis,
Table 11.21). The report identified limited evidence or mixed signals regarding a human contribution to observed
meteorological and hydrological drought in western, central, and eastern North America, with one exception: it noted
that there was evidence that human-induced temperature increases were the main driver of increased hydrological
drought in California and the Colorado River Basin (pp. 11-229 to 11-330).
24 The nonstationarity of a process such as drought consists of an exhibited shift in the process’s mean, variance, or
shape. Climate variability, climate change, land use changes, and water management changes are possible contributors
to nonstationarities in hydrological extremes such as droughts and floods.
25 Louise J. Slater et al., “Nonstationary Weather and Water Extremes: A Review of Methods for Their Detection,
Attribution, and Management,” Hydrology and Earth System Sciences, vol. 25, no. 7 (2021), pp. 3897-3935.
26 The U.S. Drought Monitor represents a consensus view between academic and federal scientists of ongoing drought
conditions. The U.S. Drought Monitor is produced jointly by the National Drought Mitigation Center at the University
of Nebraska–Lincoln, NOAA, and the U.S. Department of Agriculture (USDA). For more information, see U.S.
Drought Monitor, “What Is the USDM,” at https://droughtmonitor.unl.edu/About/WhatistheUSDM.aspx.
27 NOAA, “NOAA Drought: Science, Observations, and Services,” July 15, 2021, PowerPoint presentation. Key
indicators and indexes include the Palmer Drought Index, the Climate Prediction Center soil moisture model, USGS
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D0 (abnormally dry), D1 (moderate), D2 (severe), D3 (extreme), and D4 (exceptional)—depicts
broad-scale conditions but not necessarily drought circumstances at the local scale. The estimated
drought intensity can be a trigger for local, state, and federal responses to drought. For example,
the regions depicted as red in Figure 1 faced extreme drought conditions for the week preceding
July 27, 2021, but they may have contained local areas and individual communities that
experienced less or more severe drought.
In addition to the color-coded D0-D4 designations, U.S. Drought Monitor maps often include “S”
and “L” designations to provide additional information about the nature of drought (Figure 1).
The “S” designation indicates the existence of short-term effects: a combination of different
drought indexes that approximates responses to precipitation over days up to a few months. These
effects would include impacts to agriculture, topsoil moisture, unregulated streamflows, and
aspects of wildfire danger. The “L” designation indicates the existence of long-term effects; it
approximates responses to precipitation over several months up to a few years. These effects
include reservoir levels, groundwater, and lake levels. As Figure 1 shows, some regions of the
United States include both an “S” and an “L” designation, indicating that in July 2021, those
regions experienced both short- and long-term impacts.
Figure 1. Example of a U.S. Drought Monitor Map

Source: U.S. Drought Monitor at https://droughtmonitor.unl.edu/.
Note: U.S. Drought Monitor national maps are updated weekly.

weekly streamflow data, the Standardized Precipitation Index, and short- and long-term drought indicator blends. For a
discussion of drought indicators, see NOAA, National Centers for Environmental Information, “Drought: The
Importance of Drought Indicators,” at https://www.ncdc.noaa.gov/news/drought-importance-drought-indicators.
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Since the U.S. Drought Monitor began in 2000, some portion of the land area of the United States
has experienced drought of at least moderate intensity (D1) each year (Figure 2).28 The land area
affected by drought can vary widely by year and within a particular year. There is particular
concern about locations experiencing the most intense drought conditions: extreme and
exceptional drought (D3 and D4, respectively). Some portion of the country has experience
extreme (D3) or exceptional (D4) drought in nearly every year since 2000 (Figure 2).29
Figure 2. Percentage of United States in U.S. Drought Monitor Categories
(January 4, 2000, through September 7, 2021)

Source: U.S. Drought Monitor, “Time Series,” at https://droughtmonitor.unl.edu/DmData/TimeSeries.aspx.
Modified by CRS.
Note: Includes the continental United States and Puerto Rico.
Drought may affect certain regions of the United States on a short-term or a longer-term basis,
with varying intensity over time. For example, the Northeast region has rarely experienced
extreme (D3) or exceptional drought (D4) since the U.S. Drought Monitor began issuing maps in
2000 (Figure 3).30 In contrast, periods of extreme and exceptional drought have been relatively
common since 2000 in the western region of the United States.31

28 U.S. Drought Monitor, “Time Series,” at https://droughtmonitor.unl.edu/DmData/TimeSeries.aspx. A 2013 article
stated that, based on a monthly precipitation and mean temperature drought indicator, each decade from 1900 through
2012 had experienced drought episodes that covered 30% or more (by area) of the contiguous United States (Thomas
C. Peterson et al., “Monitoring and Understanding Changes in Heat Waves, Cold Waves, Floods, and Droughts in the
United States: State of Knowledge,” Bulletin of the American Meteorological Society, vol. 94, no. 6 [June 2013], p.
827).
29 There have been some periods since 2000 where extreme (D3) or exceptional (D4) drought did not affect any portion
of the country. For example, from January 2000 through early April 2000 and more recently, from late March 2019
through mid-March 2020.
30 The Northeast region includes Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New
Jersey, New York, Pennsylvania, Rhode Island, Vermont, and West Virginia.
31 The western region includes Arizona, California, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, and
Washington, also referred to as the West.
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Figure 3. Percentage of the Northeast and the West in
U.S. Drought Monitor Categories
(January 4, 2000, through September 7, 2021)

Source: U.S. Drought Monitor, “Time Series,” at https://droughtmonitor.unl.edu/DmData/TimeSeries.aspx.
Modified by CRS.
Some regions may experience extreme and exceptional drought more often than other areas.
Figure 4 illustrates how drought can stretch across nearly the entire nation or can affect only a
comparatively small region. On July 17, 2012, abnormally dry or drought conditions (D1-D4)
covered roughly 81% of the United States, with about 42% of the nation experiencing severe
drought or worse (D2-D4). In contrast, on July 20, 2021, about 54% of the country faced
abnormally dry or drought conditions (D1-D4), with 38% experiencing severe drought or worse
(D2-D4).32

32 U.S. Drought Monitor, “Compare Two Weeks,” at https://droughtmonitor.unl.edu/Maps/CompareTwoWeeks.aspx.
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Figure 4. Comparing Widespread and Regional Drought

Source: U.S. Drought Monitor, “Compare Two Weeks,” at https://droughtmonitor.unl.edu/Maps/
CompareTwoWeeks.aspx. Modified by CRS.
Drought Forecasts for the United States
Predicting drought is difficult, because the ability to forecast surface temperature and
precipitation depends on a number of key variables, such as air-sea interactions, topography, soil
moisture, land surface processes, and weather systems at the global scale (e.g., ENSO).33
Scientists seek to understand how these variables interact; however, it may be impossible to
reliably forecast temperate regions a season or more in advance.34
Similarly, predicting the onset of drought remains difficult.35 The drought onset forecasting
challenge is due, in part, to limitations in accurately predicting precipitation beyond a two-week
period.36 Other factors, such as land cover changes, dam operation, irrigation works, groundwater
extraction, and other engineered changes, also confound understanding of hydrologic extremes
such as drought.
Although forecasting drought at the regional scale is difficult, understanding potential changes in
long-term trends is important for water managers at all levels—federal, state, local, and tribal.
Water project operations and state water allocations typically are based on past long-term
hydrological trends; significant deviations from such trends may result in challenges for water
managers and water users alike.37
In spite of these challenges, NOAA periodically releases monthly and seasonal U.S. drought
outlooks. According to the agency, the outlooks are based on temperature and precipitation
outlooks, including seasonal and multiyear patterns of precipitation, various short- and medium-

33 National Drought Mitigation Center, “Predicting Drought,” at https://drought.unl.edu/Education/DroughtIn-depth/
Predicting.aspx.
34 Drought.gov, “Challenges with Predicting Drought,” at https://www.drought.gov/forecasts#challenges.
35 NIDIS and National Drought Resilience Partnership (NDRP), Second National Drought Forum, July 30-31, 2019,
Washington, DC, December 2020, p. 13, at https://www.drought.gov/sites/default/files/2020-12/
SecondNationalDroughtForumReport.pdf. Hereinafter, NIDIS and NDRP, Second National Drought Forum, 2020.
36 NIDIS and NDRP, Second National Drought Forum, 2020, p. 13.
37 P. C. D. Milly et al., February 2008, “Stationarity Is Dead: Whither Water Management?,” Science, vol. 319, no.
5863 (February 2008), p. 574.
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range forecasts and models, and previous U.S. Drought Monitor maps.38 The outlooks depict
areas of the United States where drought is likely to persist, improve, or develop in the next
month to several months (Figure 5). In addition, to inform stakeholders of the potential for a
flash drought, NOAA has begun to issue an experimental forecast depicting where potential flash
drought may develop in the next 30 days.39
Figure 5. U.S Monthly and Seasonal Drought Outlooks
(September 2021 and September 1-November 30, 2021, respectively)

Source: U.S. Drought Monitor, “Outlooks,” at https://droughtmonitor.unl.edu/ConditionsOutlooks/
Outlooks.aspx. Modified by CRS.
Federal Drought Policy and Coordination
The federal government generally defers to state primacy in surface and groundwater allocation,
and states and local entities typically lead efforts to prepare for drought. Most states have drought
plans in some form, and some of these plans incorporate efforts to reduce drought
vulnerabilities.40 Some states and communities have invested in reducing water demand and
expanding drought-resilient supplies (e.g., wastewater reuse and recycling, desalination, and
groundwater recharge and management) or have facilitated water banks and markets for water

38 NOAA National Weather Service, Climate Prediction Center, “Discussion for the Monthly Drought Outlook,” at
https://www.cpc.ncep.noaa.gov/products/expert_assessment/mdo_discussion.php; “Discussion for the Seasonal
Drought Outlook,” at https://www.cpc.ncep.noaa.gov/products/expert_assessment/sdo_discussion.php; and NOAA,
Climate.gov, “Data Snapshot Details: Monthly Drought Outlook,” at https://www.climate.gov/maps-data/data-
snapshots/data-source-drought-outlook.
39 NOAA, “NOAA Drought: Science, Observations, and Services,” July 15, 2021, PowerPoint presentation; and NOAA
National Weather Service, Climate Prediction Center, “Flash Drought,” at https://www.cpc.ncep.noaa.gov/products/
Drought/Flash_Drought/tendency_forecast.php.
40 NDMC collects information on state drought plans; for more information on state plans, see NDMC, “Information by
State,” at https://drought.unl.edu/droughtplanning/InfobyState.aspx.
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transfers. Community-level drought plans are less widespread than state plans, except in states
that require or support this planning.
Multiple federal agencies contribute to efforts to predict, plan for, and respond to drought. Federal
financial aid to lessen the impacts of drought, after its onset, occurs mostly in the form of
financial aid for agricultural production loss. Some federal authorities provide financial assistance
for other aspects of drought (e.g., drought-related planning or projects), but these programs are
limited in scope and authority. In localities or watersheds with major projects managed by
USACE or the Bureau of Reclamation, the federal role in water management is more direct and
can be especially controversial during times of drought, when multiple users are competing for
water.
Federal agency actions are primarily coordinated under two mechanisms, the National Integrated
Drought Information System (NIDIS) and the National Drought Resiliency Partnership (NDRP).
In 2006, Congress directed the Under Secretary of Commerce for Oceans and Atmosphere, also
known as the NOAA Administrator, to create NIDIS (P.L. 109-430). Congress modified the
NIDIS authorization in 2014 and 2019 (P.L. 113-86 and P.L. 115-423, respectively). NIDIS is
primarily focused on drought-related research and communication and is currently tasked with the
following:
 Providing a drought early warning system on a national and regional scale
 Communicating drought forecasts, conditions, and impacts on an ongoing basis
to federal and nonfederal entities
 Providing “timely” data, information, and products at the local, regional,
watershed, and state scales
 Coordinating and integrating federal research and monitoring in support of the
early warning system
 Using existing forecasting and assessment programs and partnerships
 Continuing ongoing research and monitoring activities related to drought
NIDIS is composed of representatives from federal agencies and nonfederal entities (e.g.,
nongovernmental organizations and local governments).41 The group collaborates with additional
regional and state partners, as well.42
In 2013, President Obama created NDRP as a “complement” to NIDIS.43 NDRP aims to
coordinate federal drought policies, facilitate access to drought assistance, and improve
information sharing to help with drought preparedness. NDRP currently has representatives from
multiple federal departments and agencies.44 In October 2020, the Trump Administration’s
Executive Order 13956, “Modernizing America’s Water Resource Management and Water
Infrastructure,” tasked NDRP with implementing the “Priority Actions Supporting Long-Term

41 NIDIS, Drought.gov, “Who We Are,” at https://www.drought.gov/about/who-we-are.
42 NIDIS, Drought.gov, “Partners,” at https://www.drought.gov/about/partners. For more information on NIDIS,
contact Eva Lipiec, Analyst in Natural Resources Policy.
43 NOAA, Climate Program Office, “President Signs NIDIS Reauthorization Act,” March 7, 2014, at
https://cpo.noaa.gov/News/News-Article/ArtMID/6226/ArticleID/1275/President-signs-NIDIS-Reauthorization-Act.
NDRP was “institutionalized” by President Obama in a presidential memorandum in 2016 (Executive Office of the
President, “Building National Capabilities for Long-Term Drought Resilience,” 81 Federal Register 16053, March 25,
2016).
44 NIDIS, Drought.gov, “Partners,” at https://www.drought.gov/about/partners.
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Drought Resilience” document, issued on July 31, 2019.45 The document set out specific actions
(for which it assigned specific lead agencies) related to accomplishing various policy goals
identified in the NDRP charter regarding drought information, preparedness approaches, and
technologies.
In April 2021, the Biden Administration announced the creation of the Drought Relief
Interagency Working Group, which is cochaired by the Department of the Interior (DOI) and
USDA, with representatives from multiple federal entities. The group is initially working to
identify immediate financial and technical assistance for impacted irrigators and tribes, and it is
undertaking other activities to address drought conditions in the West and to support farmers,
tribes, and communities impacted by water shortages.46 Long-term goals include the development
of measures to “respond to climate change and build more resilient communities and protect the
natural environment,” through President Biden’s proposed American Jobs Plan and a
“recommitment to strengthening” NDRP.47
Selected Federal Response Authorities
Congress has enacted a range of authorities related to drought. Some of these authorities deal with
drought-related monitoring and research, including early warning and tracking of various drought
metrics and conditions. Other authorities involve response to the onset of drought and its effects
(e.g., agriculture-related disaster authorities and emergency drinking water supply assistance).
Still others focus on longer-term drought response and mitigation. These authorities can take
multiple forms, including federal assistance for local and state drought planning and for
nonfederal water supply projects that increase drought resilience or provide new water supplies,
as well as the construction of new or expanded federal water storage projects and the reoperation
of existing projects to yield additional water supplies. In some cases, the federal government, at
Congress’s direction, also has provided targeted regulatory relief for drought-stricken areas (e.g.,
relaxation of environmental requirements on pumping water).
Selected federal drought response authorities are discussed below. The discussion focuses on
agricultural, natural resources, and environmental authorities that directly relate to drought and
does not include broader disaster authorities that might be applicable to drought under specific
circumstances,48 or available to help mitigate future drought-related damage.49

45 Executive Order 13956 directed the Water Subcabinet (composed of the Secretary-level representatives from the
Departments of Agriculture, the Army, Commerce, Energy, and the Interior, as well as the U.S. Environmental
Protection Agency) to implement the priority actions identified in the report (Executive Order 13956, “Modernizing
America’s Water Resource Management and Water Infrastructure,” 85 Federal Register 65647, October 13, 2020.).
46 Department of the Interior (DOI), “White House Launches Drought Relief Working Group to Address Urgency of
Western Water Crisis,” press release, April 21, 2021, at https://www.doi.gov/pressreleases/white-house-launches-
drought-relief-working-group-address-urgency-western-water-crisis. Hereinafter, DOI, “Drought Relief Working
Group” and White House, “Readout of the Third National Climate Task Force Meeting,” press release, April 21, 2021,
at https://www.whitehouse.gov/briefing-room/statements-releases/2021/04/21/readout-of-the-third-national-climate-
task-force-meeting/.
47 DOI, “Drought Relief Working Group.”
48 For an introduction to these authorities, see CRS Insight IN11696, Climate Change, Slow-Onset Disasters, and the
Federal Emergency Management Agency, by Diane P. Horn, Erica A. Lee, and Elizabeth M. Webster.
49 FEMA Hazard Mitigation Assistance programs, such as the Hazard Mitigation Grant Program and the Building
Resilient Infrastructure and Communities (BRIC) program, can potentially provide funding for mitigation of drought-
related damage. See CRS Insight IN11515, FEMA Pre-Disaster Mitigation: The Building Resilient Infrastructure and
Communities (BRIC) Program, by Diane P. Horn and CRS Insight IN11733, Recent Funding Increases for FEMA
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Monitoring and Research
Congress has directed federal agencies to support forecasting, warning, monitoring, and related
research activities. The primary federal agency with such responsibilities is NOAA. According to
the agency, NOAA’s drought-related monitoring responsibilities primarily fall under several
authorities, including the following:
 National Climate Program Act (P.L. 95-367, as amended)
 Global Change Research Act of 1990 (P.L. 101-606)
 Weather Service Modernization Act of 1992 (P.L. 102-567)
 National Integrated Drought Information System Act of 2006 (P.L. 109-430, as
amended)
 Weather Research and Forecasting Innovation Act of 2017 (P.L. 115-25, as
amended)
Under these authorities, NOAA supports drought-related observations, data, forecasts, modeling,
research, products, and services for use across the agency, as well as by other federal agencies,
tribal, state, and local governments, and individuals. NOAA’s observations and data come from
several sources, including geostationary and polar-orbiting weather satellites, historical climate
records and reconstructions, and direct on-the-ground field observations.50 Resulting products and
services contribute to global, national, and regional drought-related indexes, the U.S. Drought
Monitor, Drought.gov, and large-scale reports (e.g., National Climate Assessment and IPCC
reports), among others.51 As discussed above, NOAA’s NIDIS program is the federal
government’s primary drought-related research and communication hub and serves as a
coordinating mechanism for federal drought-related monitoring and research.52
USDA also carries out monitoring and research activities related to drought. In addition to its role
providing direct support, USDA conducts research and data collection related to drought and
water supply, such as drought-tolerant crop varieties, evapotranspiration modeling, drought-
resilient management techniques and practices, and soil moisture capacity and retention.53 Many
of these research projects and programs are collaborative efforts with other federal and state
agencies and with universities. For example, USDA’s Snow Survey and Water Supply
Forecasting Program (SSWSF) conducts snow surveys and develops water supply forecasts for
western states. USDA’s Natural Resources Conservation Service administers the program, using
over 900 automated data collection sites in NRCS’s Snow Telemetry (SNOTEL) network.54
Another USDA monitoring network, the Soil Climate Analysis Network, takes hourly readings of

Hazard Mitigation Assistance, by Diane P. Horn. Note that FEMA uses the term mitigation rather than adaptation,
defining mitigation as “any sustained action to reduce or eliminate long-term risk to people and property from natural
hazards and their effects”.
50 NOAA, “NOAA Drought: Science, Observations, and Services,” July 15, 2021, PowerPoint presentation.
51 NOAA, “NOAA Drought: Science, Observations, and Services,” July 15, 2021, PowerPoint presentation.
52 For more information on NOAA monitoring and research activities, contact Eva Lipiec, Analyst in Natural
Resources Policy.
53 For more information on USDA research activities, see CRS Report R40819, Agricultural Research: Background
and Issues, by Genevieve K. Croft, or contact Genevieve Croft, Analyst in Agricultural Policy.
54 The Snow Survey and Water Supply Forecasting Program is authorized under 26 Stat. 653, as amended, and
Reorganization Plan No. IV, as a provision of the Reorganization Act of 1939, as amended (54 Stat. 1234). For more
information on this program and the Natural Resources Conservation Service (NRCS’s) Snow Telemetry network, see
USDA, NRCS, “Snow Program Overview,” at https://www.nrcs.usda.gov/wps/portal/wcc/home/aboutUs/
snowProgramOverview/.
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soil moisture content at over 200 stations. The data collected at both SSWSF and SNOTEL sites
are used to make water supply forecasts.
Other federal agencies with authorities related to drought monitoring and research include the
U.S. Geological Survey (USGS), National Aeronautics and Space Administration, and the Bureau
of Reclamation.55 For example, USGS maintains a network of streamgages across the United
States. Streamgage information is a key component of the weekly U.S. Drought Monitor maps
and classifications.56 Multiple federal agencies also work together to support research and
monitoring under NIDIS, NDRP, and other partnerships, depending on the issue area. For
example, the 2019 NIDIS Reauthorization Act (P.L. 115-423) directed the NOAA Administrator
to develop a strategy for a national coordinated soil moisture monitoring network. As part of the
strategy, NIDIS, NOAA, USGS, and USDA have supported a joint research effort to develop and
share near-real-time soil moisture information.57
USDA Drought Support Programs for Farmers and Ranchers
Although many factors (e.g., pest infestation, flooding, hail) can pose major production
challenges to farmers, drought is the most significant agricultural risk in the United States in
terms of production and income loss.58 Due to the complex way in which plants and livestock
respond to heat and water availability, the effect of drought on crops and livestock can be highly
variable depending on what is being produced, how, and where. For example, dryland farms with
shallow soils may experience a significant loss in production during a moderate drought, whereas
irrigated production with ample groundwater may experience negative impacts only during an
extreme drought.59 Soil structure and soil moisture retention, as well as access to ground or
surface water, also can heavily influence the level of agricultural production loss from drought.
Congress has authorized support for farmers and ranchers to manage drought risk, pay for losses
caused by drought, and incentivize adaptive measures. USDA administers these federal assistance
programs, which include direct payments for loss, subsidized insurance, cost sharing to
rehabilitate damaged lands, loans, and financial and technical assistance to implement
conservation practices. Most programs have permanent authorization and aim to assist producers
recovering from production, financial, and physical loss related to or caused by natural disasters,
such as drought. Each program has a different administrative process for producers requesting
assistance. Only the loan programs require a disaster declaration or designation for eligibility
(discussed further in “Loans,” below).60 USDA programs that do not provide direct financial

55 For more information about ongoing and planned drought-related data collection and integration activities at these
agencies, see NDRP, Priority Actions Supporting Long-Term Drought Resilience, 2019, pp. 3-7, at
https://www.hsdl.org/?view&did=829959 and Drought.gov, “Partners,” at https://www.drought.gov/about/partners.
56 See U.S. Drought Monitor, “Drought Classification,” at https://droughtmonitor.unl.edu/About/AbouttheData/
DroughtClassification.aspx. For more information about USGS streamgages, see CRS Report R45695, U.S. Geological
Survey (USGS) Streamgaging Network: Overview and Issues for Congress, by Anna E. Normand, or contact Anna
Normand, Analyst in Natural Resources Policy.
57 Drought.gov, “NationalSoilMoisture.com,” at https://www.drought.gov/data-maps-tools/nationalsoilmoisturecom.
58 Steven Wallander, Elizabeth Marshall, and Marcel Aillery, “Farms Employ Strategies to Reduce Risk of Drought
Damages,” USDA, Economic Research Service, Amber Waves, June 5, 2017, at https://www.ers.usda.gov/amber-
waves/2017/june/farmers-employ-strategies-to-reduce-risk-of-drought-damages/. Hereinafter, Wallander, Marshall, and
Aillery, “Drought Damages.”
59 Wallander, Marshall, and Aillery, “Drought Damages.”
60 For additional information on the USDA disaster assistance programs, see CRS Report RS21212, Agricultural
Disaster Assistance, by Megan Stubbs; and CRS Report R42854, Emergency Assistance for Agricultural Land
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support for agricultural producers are discussed in “Other Drought Authorities: Support for
Nonfederal Drought Planning and Projects,” below.
Direct Payments
Some USDA programs provide payments to cover production losses above normal mortality.
Advance sign-up and fees are not required to participate; however, application deadlines exist
following a qualified loss. These programs are permanently authorized and receive mandatory
funding amounts of “such sums as necessary.”61 USDA’s Farm Service Agency (FSA)
administers the following direct payment programs, for which producers may file applications
through local FSA offices.62
 Livestock Forage Disaster Program (LFP). LFP provides payments to eligible
livestock producers who suffered a loss of grazing forage for covered livestock
due to drought on privately owned or cash-leased pastureland (including cropland
planted specifically for grazing).63 A county’s U.S. Drought Monitor intensity
level and the drought severity and duration trigger payment. LFP payments for
drought are equal to 60% of the monthly feed cost for all covered livestock for up
to five months, depending on the drought’s severity. For producers who sold
livestock because of drought conditions, the payment rate is equal to 80% of the
estimated monthly feed cost.
 Livestock Indemnity Program (LIP). LIP provides payments to eligible
livestock owners and contract growers for livestock deaths in excess of normal
mortality caused by adverse weather. Drought is not an eligible adverse weather
event, except when associated with anthrax, a disease that may occur because of
drought and directly results in the death of eligible livestock.64
 Emergency Assistance for Livestock, Honey Bees, and Farm-Raised Fish
Program (ELAP). ELAP provides payments to producers of livestock,
honeybees, and farm-raised fish as compensation for losses due to disease,
adverse weather, feed or water shortages, or other conditions not covered under
LIP or LFP. ELAP may cover the cost of transporting water but not the cost of
water.
 Tree Assistance Program (TAP). TAP makes payments to qualifying orchardists
and nursery tree growers to replant or rehabilitate trees, bushes, and vines
damaged by natural disasters, including excessive wind and qualifying drought.
Insurance programs generally cover losses in crop production (see “Insurance,”
below).

Rehabilitation, by Megan Stubbs.
61 The four direct-payment programs are authorized under Section 1501 of the Agricultural Act of 2014, as amended
(P.L. 113-79; 7 U.S.C. §9081). For additional information on the four programs, see CRS Report RS21212,
Agricultural Disaster Assistance, by Megan Stubbs.
62 To find a local Farm Service Agency (FSA) office, see https://offices.sc.egov.usda.gov/locator/app.
63 Fire is also an eligible cause of loss on rangeland managed by a federal agency.
64 Anthrax is caused by Bacillus anthracis, a spore-forming bacterium that can survive in the soil for decades. Hoofed
animals (e.g., cattle, goats, sheep) are the main animals affected by this disease. Outbreaks usually occur after periods
of drought followed by heavy rains. Spores can become concentrated on the soil surface and on vegetation, where
foraging animals can become exposed to the disease. For additional information, see American Veterinary Medical
Association, “Anthrax Facts,” December 4, 2001, at https://www.avma.org/anthrax-facts.
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U.S. Drought Monitor and USDA Programs
The U.S. Drought Monitor is a map that identifies areas of drought and drought intensity using four levels of
drought intensity (see “Drought Classification”). Congressional interest in the U.S. Drought Monitor has grown in
recent years, as additional U.S. Department of Agriculture (USDA) program benefits have become tied to it.
Below are examples of how both Congress and USDA have increasingly relied on the U.S. Drought Monitor as a
mechanism for triggering drought assistance in USDA programs.

Beginning in 2003, USDA used the U.S. Drought Monitor to determine state and county eligibility to
distribute nonfat dry milk surplus stocks for livestock feed in areas experiencing extreme or exceptional
drought (D3 or D4 classifications).

In the Food, Conservation, and Energy Act of 2008 (2008 farm bill; P.L. 110-246), Congress required that
specific drought intensity classifications published in the U.S. Drought Monitor be used as triggers for
payments under the Livestock Forage Disaster Program (LFP). Subsequent reauthorizations of LFP have
retained this funding mechanism and reliance on the U.S. Drought Monitor.

In 2012, USDA amended the secretarial disaster designation process used to trigger emergency farm loans
(see “Loans”) by creating an expedited process—referred to as a fast-track designation—for severe drought
situations. This fast-track process is based on drought intensity levels from the U.S. Drought Monitor. The
process has allowed USDA to issue secretarial disaster designations nearly automatically during periods of
severe drought (D2 or higher), expediting access to aid and reducing reporting requirements at the Farm
Service Agency (FSA) office level.

The Agriculture Improvement Act of 2018 (2018 farm bill; P.L. 115-334) amended the Conservation Reserve
Program (CRP; see “Conservation”) to allow emergency haying and grazing on selected CRP acres when a
county is experiencing drought classified as severe (D2) or greater.

In the FY2020 Further Consolidated Appropriations Act (P.L. 116-94), Congress repurposed funding for the
Wildfires and Hurricanes Indemnity Program to cover losses related to drought, among other loss types.
Drought-related losses must have occurred in counties with a D3 (extreme) or D4 (exceptional)
classification in calendar years 2018 and 2019.
Sources: USDA, FSA, “Sale of Surplus Non-fat Dry Milk,” fact sheet, April 2003, at https://www.fsa.usda.gov/
Internet/FSA_File/nfdm03.pdf; USDA, FSA, “Disaster Designation Process,” 77 Federal Register 41248, July 13,
2012; and CRS In Focus IF11539, Wildfires and Hurricanes Indemnity Program (WHIP), by Megan Stubbs.
Insurance
USDA administers two insurance programs that offer subsidized or federally supported insurance
coverage for yield, revenue, or other financial losses associated with production of eligible crops
and livestock. Coverage is available for adverse weather conditions, including natural disasters,
and, in some cases, market declines. Most policies consider drought and related conditions, such
as extreme heat and irrigation water supply failure, eligible causes of losses. Coverage is
available for catastrophic losses—losses in excess of 50% of normal yield. Higher coverage
levels may be purchased for less severe losses (referred to as buy-up coverage).65 Policies must be
purchased prior to a disaster event, and producers must purchase or renew coverage on an annual
basis. These programs are permanently authorized and have mandatory funding authority.
 Federal Crop Insurance Program (FCIP). FCIP offers farmers the opportunity
to purchase insurance coverage against financial losses caused by various perils,
including certain adverse growing and market conditions.66 Crop insurance is

65 Buy-up coverage is available in increments of 5% through the Federal Crop Insurance Program (FCIP) to cover
between 50% and 85% of a crop and through the Noninsured Crop Disaster Assistance Program (NAP) to cover
between 50% and 65% of a crop. For example, a NAP policy with buy-up coverage of 60% would insure losses greater
than 40% of the expected yield and provide no coverage for losses amounting to less than 40% of expected yield.
66 FCIP is authorized by the Federal Crop Insurance Act, as amended (P.L. 96-365; 7 U.S.C. §§1501 et seq.). For more
information on FCIP, contact Stephanie Rosch, Analyst in Agriculture Policy, or see CRS Report R46686, Federal
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available for most major crops, many specialty crops (e.g., fruit, tree nut,
vegetable, and nursery crops), forage and pastureland for livestock producers,
and revenues from dairy and livestock production. USDA’s Risk Management
Agency administers the program, and approved private insurance companies sell
and service federal crop insurance policies. Producers must contact their crop
insurance agents to file a claim following a loss.67
 Noninsured Crop Disaster Assistance Program (NAP). NAP provides
coverage for crops and in locations where FCIP insurance is unavailable.68 NAP
applicants must pay an administrative fee at the time of application, plus any
additional cost for buy-up coverage. FSA administers NAP, and producers must
notify their local FSA office following a loss.
Cost-Share Assistance
Some USDA programs pay a percentage of the cost to reinstall conservation infrastructure or
rehabilitate damaged land. Advance sign-up generally is not required. However, the programs will
not pay for impairments existing before the disaster event. FSA administers the following cost-
share programs, for which producers may file applications through local FSA offices. These
programs are permanently authorized but subject to appropriations.69
 Emergency Conservation Program (ECP). ECP assists landowners in restoring
land used in agricultural production damaged by a natural disaster and in
implementing emergency water-conservation measures in severe drought periods.
Eligible activities may include providing emergency water for livestock and
existing permanently installed irrigation systems for orchards and vineyards.
 Emergency Forest Restoration Program (EFRP). EFRP provides cost-share
assistance to private forestland owners to repair and rehabilitate damage caused
by natural disasters, including drought, on nonindustrial private forestland.
Eligible practices may include removing debris and replanting to restore forest-
related damage from drought.
Loans
USDA can provide low-interest loans to help producers recover from production or physical
losses due to drought and other natural disasters, or it can provide temporary loan relief for
existing FSA farm loans. These loan options are triggered when a county is designated as a
disaster area under a presidential major disaster declaration, a presidential emergency declaration
pursuant to the Robert T. Stafford Disaster Relief and Emergency Assistance Act (Stafford Act; 42
U.S.C. §§5121 et seq.), or a USDA secretarial disaster designation. Although Stafford Act
declarations related to drought are uncommon, USDA issues a secretarial disaster designation
nearly automatically during periods of severe drought under a fast-track process in accordance

Crop Insurance: A Primer, by Stephanie Rosch.
67 To locate an approved insurance provider, visit https://prodwebnlb.rma.usda.gov/apps/AgentLocator/#/.
68 NAP is authorized under Section 196 of the Federal Agriculture Improvement and Reform Act of 1996, as amended
(P.L. 104-127; 7 U.S.C. §7333). For additional information on NAP, see CRS Report RS21212, Agricultural Disaster
Assistance, by Megan Stubbs.
69 The cost-share assistance programs are authorized under Title IV of the Agricultural Credit Act of 1978 (P.L. 95-
334; 16 U.S.C. §§2201-2206). For additional information on the programs, see CRS Report R42854, Emergency
Assistance for Agricultural Land Rehabilitation, by Megan Stubbs.
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with U.S. Drought Monitor intensity (see text box on “U.S. Drought Monitor and USDA
Programs,” above). FSA administers the loan programs, and local FSA offices accept
applications. USDA loan programs are subject to appropriations.70
 Emergency Farm Loans. Loans may help producers recover from production
and physical losses.71 A qualified applicant can borrow up to 100% of actual
production (e.g., loss of a crop) or physical losses (e.g., repairing or replacing
damaged or destroyed structures or replanting permanent crops, such as
orchards). Loan totals may not exceed $500,000. A producer must operate in a
county declared eligible or in a contiguous county and must meet the loan
requirements.
 Disaster Set-Aside. A producer with an existing FSA farm ownership or
operating loan located in a designated disaster area or contiguous county may
apply to set aside one payment to allow the operation to continue.72 The payment
set-aside is not forgiven and must be repaid prior to final maturity of the note.
Any principal set-aside will continue to accrue interest until repaid.
Conservation
Certain USDA conservation programs that are not emergency programs may provide assistance
during drought periods to help alleviate drought’s impacts on agricultural production.73 In many
cases, this assistance comes through the use of waivers and flexibility provided to the Secretary of
Agriculture. Other assistance is offered through adaptive measures that reduce drought risk
through various management decisions and practices, which are not discussed in detail in this
report.74
 Conservation Reserve Program (CRP). CRP uses mandatory funding to
provide annual payments to agricultural producers to take highly erodible and
environmentally sensitive land out of production and install resource-conserving
practices for 10 or more years.75 Haying and grazing may occur on CRP acres

70 For more information on USDA loan programs, see CRS Report R46768, Agricultural Credit: Institutions and
Issues, by Jim Monke.
71 Emergency farm loans are authorized under Title III of the Consolidated Farm and Rural Development Act, as
amended (7 U.S.C. §§1961 et seq.) For more information, see USDA, FSA, “Emergency Farm Loans,” at
https://www.fsa.usda.gov/programs-and-services/farm-loan-programs/emergency-farm-loans/index.
72 The Disaster Set-Aside Program is authorized under Section 331A of the Consolidated Farm and Rural Development
Act, as amended (7 U.S.C. §1981a). For more information see, USDA, FSA, “Disaster Set-Aside Program,” fact sheet,
August 2019, at https://www.fsa.usda.gov/Assets/USDA-FSA-Public/usdafiles/FactSheets/2019/disaster-set-aside-
program-factsheet-19.pdf.
73 For additional information on USDA conservation programs generally, see CRS Report R40763, Agricultural
Conservation: A Guide to Programs, by Megan Stubbs.
74 Examples of adaptive measures include soil health practices—such as no till or reduced tillage, cover crop adoption,
and conservation crop rotations—that can increase soil organic matter over time and reduce soil moisture loss.
Adoption of irrigation efficiency practices—such as variable-rate irrigation, flow meters, land leveling, and soil
moisture sensors—generally reduces evaporation and runoff loss but also may impact ground water infiltration and
downstream water availability. For additional information on USDA adaptation activities, see CRS Report R46454,
Climate Change Adaptation: U.S. Department of Agriculture, coordinated by Genevieve K. Croft.
75 The Conservation Reserve Program (CRP) is authorized under Title XII of the Food Security Act of 1985, as
amended (P.L. 99-198; 16 U.S.C. §§3831-3835). For additional information on CRP emergency haying and grazing,
see USDA, FSA, “CRP Haying and Grazing: Emergency and Non-Emergency Use,” fact sheet, May 2021, at
https://www.fsa.usda.gov/Assets/USDA-FSA-Public/usdafiles/FactSheets/crp_haying_grazing_factsheet.pdf.
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under emergency and nonemergency conditions. Emergency haying and grazing
of CRP acres is generally authorized during periods of severe drought (D2 or
higher, according to the U.S. Drought Monitor) or similar natural disaster (e.g.,
wildfire).76 Outside of the primary nesting season, up to 90 days of grazing or
one cutting of hay is allowed.77 During the primary nesting season, emergency
grazing is allowed in approved counties, but at half the normal carrying capacity
and only if LFP payments also have been triggered for the county. Emergency
haying is not allowed on CRP acres during the primary nesting season. Not all
CRP practices are eligible for haying and grazing; a request must be filed with
the local FSA office before any activity begins.
 Environmental Quality Incentives Program (EQIP). EQIP is a voluntary
program that uses mandatory funding to provide financial and technical
assistance to agricultural producers to address natural resource concerns on
agricultural and forestland.78 In the past, USDA has announced special EQIP
sign-ups for farmers and ranchers in hurricane-, flood-, or drought-affected areas.
EQIP also may be used to proactively mitigate potential damage from natural
disasters through conservation practices (e.g., residue management to improve
the soil’s capacity to be more drought resilient). NRCS administers EQIP, and
applications may be filed at any local NRCS office.
Drought and Federal Facilities79
The federal government owns and operates thousands of dams as well as other infrastructure;
some of this infrastructure supports water supplies. These facilities’ operations, particularly the
water stored in reservoirs at federal dams, can both assist in meeting water supply needs during
droughts and be vulnerable to droughts. Federal dams, particularly in the West, were constructed
in part to provide multiyear storage to help with variations in seasonal and annual precipitation.
The majority of large-scale federal water resource projects are owned and managed by the two
principal federal water resource agencies: Reclamation and USACE. The discussion herein
focuses on the federal dams that form storage reservoirs operated by these two federal agencies.
Figure 6 shows the Reclamation and USACE reservoirs with capacities greater than 25,000 acre-
feet (AF) that are identified as having water supply or irrigation among their operational
purposes. 80 Federal reservoirs are distributed across the conterminous United States; in some

76 Emergency haying and grazing status is reviewed every Thursday using the U.S. Drought Monitor. Approved
counties are listed on the FSA “Emergency Haying and Grazing” website, at https://www.fsa.usda.gov/programs-and-
services/conservation-programs/conservation-reserve-program/emergency-haying-and-grazing/index.
77 The primary nesting season is established in each state as the nesting season for birds in the local area that are
economically significant, in significant decline, or conserved in accordance with federal or state law (7 C.F.R.
§1410.2). For a list of primary nesting dates and durations, see USDA, FSA, “Primary Nesting Season Dates and
Duration,” June 16, 2020, at https://www.fsa.usda.gov/Assets/USDA-FSA-Public/usdafiles/Conservation/PDF/
Primary%20Nesting%20Season_June_16_2020.pdf.
78 The Environmental Quality Incentives Program (EQIP) is authorized under Title XII of the Food Security Act of
1985, as amended (P.L. 99-198; 16 U.S.C. §§3839aa-3839aa-7). For additional information on EQIP, see USDA,
NRCS, “Environmental Quality Incentives Program,” at https://www.nrcs.usda.gov/wps/portal/nrcs/main/national/
programs/financial/eqip/.
79 For more information on Reclamation, contact Charles V. Stern, Specialist in Natural Resources Policy. For more
information on USACE, contact Nicole T. Carter, Specialist in Natural Resources Policy. For more information on the
Endangered Species Act, contact Pervaze A. Sheikh, Specialist in Natural Resources Policy.
80 An acre-foot of water is equal to the volume of a sheet of water 1 acre in area and 1 foot in depth, equivalent to
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watersheds and states, particularly in the West, federal reservoirs and related infrastructure are
prevalent and play a significant role in storing and delivering water supplies.
Reclamation is a central player in water resource management in the West. It maintains 491 dams
and other water supply infrastructure in the 17 arid and semi-arid western states (known as
reclamation states), as defined in statute.81 Reclamation’s facilities currently serve over 31
million people in the West and deliver a total of nearly 30 million AF of water annually. During
droughts, these facilities face operational challenges and particular scrutiny, in part due to
conflicts among users of the water that Reclamation facilities supply.
Figure 6. Selected Bureau of Reclamation and U.S. Army Corps of Engineers Dams
with Water Supply and/or Irrigation Purposes
(dams with storage capacities greater than 25,000 acre-feet)

Source: CRS, using data from the National Inventory of Dams (NID) and U.S. Geological Survey watershed
boundaries.
Notes: AF = Acre-Feet (see footnote 80 for more information); USACE = U.S. Army Corps of Engineers;
Reclamation = U.S. Bureau of Reclamation. As discussed in the report, municipal and industrial water supply and
irrigation water storage generally are not primary purposes of USACE projects and instead are associated with
multipurpose USACE projects. This figure refers to Reclamation and USACE as the dam owners for consistency

43,560 cubic feet of water.
81 An 1890-1896 drought coincided with a period in U.S. history of federal encouragement of large-scale efforts to
irrigate the relatively arid western states. At that time, Congress debated a larger federal role in western states’
irrigation. This debate led to the Reclamation Act of 1902, which was enacted largely to “reclaim the arid West.” The
federal government constructed hundreds of dams, reservoirs, and related facilities to provide water to local farmers to
reclaim the arid West through irrigation of arid lands. Today, Reclamation is responsible for managing and developing
many of the large federal dams and water diversion structures in the 17 coterminous states west of the Mississippi
River (referred to as reclamation states): Arizona, California, Colorado, Idaho, Kansas, Montana, Nebraska, Nevada,
New Mexico, North Dakota, Oklahoma, Oregon, South Dakota, Texas, Utah, Washington, and Wyoming. For more
information, see CRS Report R46303, Bureau of Reclamation: History, Authorities, and Issues for Congress, by
Charles V. Stern and Anna E. Normand.
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with NID classifications, although Reclamation and USACE dams are ultimately owned by the federal
government.
In contrast, USACE facilities operate throughout the United States and typically have not focused
on water supply storage as a principal project purpose; instead, water supply storage is often a
secondary purpose of multipurpose USACE facilities. Sustained hydrological drought nonetheless
affects operations of USACE-managed reservoirs, dams, locks, hydroelectric facilities, and other
components of the nation’s water infrastructure. For example, numerous USACE reservoirs have
drought management plans that result in the curtailing of some benefits (e.g., navigation,
hydropower) to maintain other benefits (e.g., in-stream flows to support water quality, aquatic
species, and river withdrawals for electric power cooling and municipal and industrial water
supplies).
Federal facilities’ ability to deliver water supplies can be curtailed during the low inflow and
storage conditions accompanying droughts. In the past, Congress has conducted oversight of
federal facilities’ ongoing operations and has been active in several other areas related to federal
reservoirs and drought, including the following:
 Providing authorities and funding to expand western water storage
 Enacting authorities related to updating operating plans for reservoirs during
drought
 Supporting developments in the area of forecast-informed reservoir operations
(FIRO) and other efforts to enhance the data used to inform operations decisions
 Allowing for regulatory relief, in some instances, for federal water resource
project operations during drought
Expanding Western Water Storage
Reclamation
Some long-term federal drought response authorities support the construction of new or expanded
water storage projects in drought-prone areas. During the 2012-2016 California drought,
Congress created a new authority for Reclamation to build water storage in Section 4007 of the
Water Infrastructure Improvements for the Nation Act (WIIN Act; P.L. 114-322).82 The authority
provided federal support for the construction of new and augmented surface water storage
projects in the 17 reclamation states.
Funding for water storage projects under Section 4007 is available for two primary project types.
Federally owned storage projects (surface water or groundwater storage projects to which the
United States holds title and which were authorized to be constructed pursuant to reclamation law
and regulations) may be no more than 50% federally funded. State-led storage projects (surface
water or groundwater storage projects constructed, operated, and maintained by states or political
subdivisions) may be no more than 25% federally funded. Prior to the WIIN Act, Congress had
not authorized Reclamation to fund state-led water storage projects.
Before the federal government can spend or contribute funding for the construction of new water
projects under this authority, several milestones must be met:

82 For more information on these projects, see CRS In Focus IF10626, Reclamation Water Storage Projects: Section
4007 of the Water Infrastructure Improvements for the Nation Act, by Charles V. Stern.
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 The Secretary of the Interior must find that the project is feasible and provides
benefits proportionate to the federal government’s cost share, and project
sponsors must agree to pay their portions of project costs up front.
 Appropriations under the Section 4007 authority are available only after (1) the
Secretary of the Interior transmits a list of recommended projects and funding
levels to Congress and (2) Congress designates those projects by name in an
enacted appropriations act.
As of mid-2021, Congress had approved Reclamation’s project-level allocations of this funding
for 12 projects in three states (California, Idaho, and Washington). Although most of the early
funding was for studies, Reclamation also recommended six projects for construction under this
authority. In the future, more projects are likely to receive funding and to begin construction
under this authority. Apart from advocating for additional appropriations, some support extension
and/or changes to Section 4007.83
USACE
Water supply storage typically is not a principal project purpose of USACE-constructed facilities
in the United States. In December 2020, Congress authorized USACE to carry out small water
storage projects,84 including for water supply and water conservation. The authority allowed
USACE to undertake construction of (1) new water storage projects with capacities between
2,000 AF and 30,000 AF or (2) enlargements between 1,000 AF and 30,000 AF of existing
storage; the authority established cost-sharing requirements based on the purpose of storage. This
authority has not been funded, and USACE has not released implementation guidance for how the
agency would act on this authority if funded. In the same 2020 legislation, Congress directed
USACE to provide the congressional authorizing committees, within 18 months of enactment, a
report that analyzes the benefits and consequences of including water supply and water
conservation as a primary mission of USACE in carrying out water resources development
projects.85
Drought Operations Manuals and Planning
Reclamation
Reclamation projects typically are governed by operating plans,86 but there is no formal
requirement for Reclamation to formally revise these plans with drought contingency plans
(DCPs)—guidance on how the project is to be operated during droughts. Most Reclamation
contracts with water users include provisions that allow Reclamation to restrict deliveries due to
water shortages and other drought-related factors, which allows for some level of operational
flexibility during drought.87 Reclamation has authority to enter into drought contingency plans; in

83 For additional information on congressional proposals related to this authority, see below section, “Congressional
Proposals in the 117th Congress.”
84 Section 155 of the Water Resources Development Act of 2020 (Division AA of P.L. 116-260). The provision limits
federal project costs to $65 million and specifies that municipal and industrial costs are 100% nonfederal and
agricultural water supply is 35% nonfederal.
85 Section 221 of the Water Resources Development Act of 2020.
86 In accordance with Section 7 of the Flood Control Act of 1944 (33 U.S.C. §709), USACE has formal responsibility
for preparing water control manuals for reclamation projects with storage space allocated for flood control purposes.
87 See Bureau of Reclamation, “Water-Related Contracts and Charges – General Principles and Requirements,”
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Section 202 of the Reclamation States Emergency Drought Relief Act of 1991 (P.L. 102-250),
Congress authorized the bureau to prepare or participate in the preparation of cooperative drought
contingency plans, for the prevention or mitigation of adverse effects of drought conditions,88 but
Congress did not specify the level of these projects. In practice, the bureau has supported
contingency plans developed by nonfederal interests (for more information, see below section,
“Bureau of Reclamation Drought Response Program and Other Authorities”). In part to facilitate
Reclamation’s ability to adapt its operations to changes in water supplies and demand, in 2009
Congress enacted Section 9503(c) of the SECURE Water Act (P.L. 111-11), which directed
Reclamation to identify and assess potential water-related risks of climate change in major
reclamation river basins and to report on these efforts at five-year intervals.89 Reclamation
published reports pursuant to the SECURE Water Act in 2011, 2016, and 2021.90 These reports,
coupled with complementary reporting in the form of West-wide climate and hydrology
assessments and individual river basin reports, highlight Reclamation’s analysis and expectations
for altered water supply and demand at a variety of geographical levels.
The SECURE Water Act also authorized Reclamation to undertake actions to address climate
change risks. The act authorized Reclamation to use specific strategies, including those related to
(1) modification of reservoir storage or operating guidelines; (2) development of new water
management, operating, or habitat restoration plans; (3) water conservation; (4) improved
hydrologic models and other decision support systems; and (5) groundwater and surface water
storage needs.91 One way Reclamation has used these authorities is by conducting a number of
reservoir operations pilot studies at specific locations in the 17 reclamation states; these studies
seek to identify operational improvements in response to variable water supplies, including
droughts. Beginning in 2015, Reclamation conducted five pilot studies.92 In June 2021,
Reclamation announced another six pilot studies in five western states.93 Initial studies employed
various approaches, including the increased use of paleohydrology, advanced monitoring, and
forecast-informed operations, among others (for more information on forecast-based operations,
see “Forecast-Informed Reservoir Operations” below).
USACE
USACE maintains water-control manuals that detail how reservoirs are to be operated given their
congressionally authorized purposes. Since the late 1970s, USACE regulations have required
USACE projects that maintain controlled reservoir storage to have a DCP. The DCP informs
water management decisions and responses to drought-related water shortages in a basin. Because
of uncertainties such as when a drought will end, DCPs generally specify a minimum suite of
actions related to water control and allow for additional actions as the specific situation warrants
(e.g., approval of deviations from operating plans).94

Reclamation Manual PEC P05, July 24, 2013, at https://www.usbr.gov/recman/pec/pec-p05.pdf.
88 43 U.S.C. §2222.
89 42 U.S.C. §10363.
90 For more information and individual reports, see https://www.usbr.gov/climate/secure/2021secure.html.
91 42 U.S.C. §10363.
92 For more information, see Reclamation, “Reservoir Operations Pilots,” at https://www.usbr.gov/watersmart/pilots/
index.html.
93 For more information, see Reclamation, “FY2021 Reservoir Operations Pilots—Round 1 Selections,” at
https://www.usbr.gov/watersmart/pilots/docs/FY21-ResOps-R1ProjectDescriptions.pdf.
94 A deviation is the operation of a USACE project in a manner other than specified in the approved water control
manual or its associated drought contingency plan (DCP). A detailed assessment is required prior to the execution of a
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In 2015, after an internal assessment of the state of USACE drought contingency planning and an
effort to develop methods to update DCPs to account for a changing climate, USACE released a
report titled USACE Drought Contingency Planning in the Context of Climate Change.95 The
report reviewed the 142 existing DCPs for USACE projects, the majority of which were
developed prior to 1993, and noted that “none of the DCPs reviewed include information about
drought projections under future climate change. Consequently, it is unlikely that these reports
provide an adequate guide for preparing for future droughts that may be longer and more intense
than recognized by these DCPs.”
In 2018, USACE updated the 1981 regulation that guided the development and updating of
DCPs.96 The 1981 regulation used the standard engineering practice of preparing DCPs based on
observed periods of record for temperature, precipitation, and drought. The 2018 regulation
identified actions that “at a minimum” its planners and engineers should do for purposes of
incorporating climate change considerations into DCP development, including the consideration
of regional variables. It remains unclear how much recent DCP efforts have accomplished toward
enhancing drought preparedness at USACE projects nationally.
Congress provided USACE with authorities related to reservoir management for drought and
water conservation activities in the last decade.97 According to USACE, limited to no action has
occurred under these authorities due to a lack of funding or interest from nonfederal partners.98
One exception is activity under the authority of Section 1116 of the WIIN Act, which authorized
USACE to study and perform water conservation measures at USACE reservoirs in certain states
that had declared droughts. USACE used this authority to evaluate and approve conservation
measures at Prado Dam, Riverside County, CA, for the purpose of downstream nonfederal
groundwater recharge efforts.99
Water supplies for communities and agriculture receive much attention during droughts, but
USACE also makes drought-related adjustments to meet its navigation mission at times. For
example, during the 2012 drought, USACE maintained navigation on the Mississippi River and
its tributaries (albeit in a narrower and shallower channel than is available in a normal water year)
using a combination of measures: dredging of critical areas, removal of rock pinnacles, and
releases of reservoir water within authorized purposes.

deviation. Since 2015, USACE has maintained a drought portal for its staff, which has expanded to include a collection
of DCPs, more than 300 approved deviations, and other drought-relevant materials. Due to portal access limitations,
CRS was unable to assess the location or frequency of drought-related deviations for different USACE projects or for
specific watersheds.
95 USACE, USACE Drought Contingency Planning in the Context of Climate Change, CWTS Report 15-15, September
2015, at https://usace.contentdm.oclc.org/digital/collection/p266001coll1/id/6727. The report team identified and
assessed 142 DCPs covering 301 projects.
96 USACE, Drought Contingency Plans, ER 1110-2-1941, February 2, 2018.
97 These authorities include provisions in the Water Resources Reform and Development Act of 2014 (WRRDA 2014;
P.L. 113-121) and the Water Infrastructure Improvements for the Nation Act (WIIN Act; P.L. 114-322). In WRRDA
2014, Section 1045, Congress authorized a USACE assessment of the effects of drought conditions on lakes managed
by the Secretary of the Army that are affected by Federal Energy Regulatory Commission-licensed reservoirs. In
Section 1046, Congress authorized a USACE assessment of the management practices, priorities, and authorized
purposes at USACE reservoirs in arid regions to determine the effects on water supply of periods of drought, among
other things. In WIIN Section 1117, Congress authorized USACE, at the request of a governor, to prioritize updating
the water control manuals for USACE operated and maintained water control structures in certain states with declared
droughts and to incorporate into the updates seasonal operations for water conservation and water supply.
98 Personal communication from USACE staff to CRS staff, July 8, 2021.
99 Personal communication from USACE staff to CRS staff, July 8, 2021.
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Forecast-Informed Reservoir Operations
Federal dam operators have often used runoff measurements and other observations (e.g.,
snowpack or soil moisture) to inform decisions related to storing or releasing water. In some
cases, operators are considering using not only measurements but also forecasts to inform inflow
estimates. Advancements in weather forecasting, in particular in detection and forecasting of
atmospheric rivers,100 have piqued decisionmakers’ interest in identifying opportunities to use
forecasts for more dynamic dam operations.101 That is, operations would move from rules that use
a single estimate of runoff to rules for making operational decisions based on ensembles of runoff
(or streamflow) forecasts and statistical techniques to simulate conditions and operations. This
reservoir management approach, referred to as forecast-informed reservoir operations, or FIRO,
uses data from watershed monitoring and from weather and water forecasting to inform water
management decisions to retain or release water from reservoirs.
Researchers and agencies have applied early FIRO efforts to reservoirs in California and the
Pacific Northwest, where atmospheric rivers often are significant contributors to precipitation. A
challenge of using FIRO to adjust reservoir operations is that although atmospheric rivers may
alleviate drought, they also can cause floods. Reservoir managers must balance maintaining
reservoir storage space to capture floodwaters during wet periods with storing water supplies to
meet demands during dry periods. Multiple factors can affect how forecasts translate into
reservoir inflows. Various federal agencies have worked together on a limited number of pilot
projects, including one applying FIRO at USACE’s Lake Mendocino in California’s Russian
River Basin.102 The facility is a USACE dam that provides flood control and stores water for
municipal and agricultural water supplies. The pilot project’s researchers documented the
viability of FIRO operations using 15-day ensemble streamflow forecasts to enhance water
supply while not significantly hampering flood risk reduction.103 USACE has temporarily
approved the use of FIRO for Lake Mendocino and is pursuing a permanent change to the
reservoir’s operations manual. The temporary deviation allows additional water to be stored in
Lake Mendocino during the winter rainy season, with the goal of improving drier-season water
supply reliability and environmental conditions in the Russian River without harming the
reservoir’s flood management function.
Reclamation and USACE also incorporated forecasts into a 2018 update to their joint Folsom
Dam Water Control Manual.104 Pursuant to the manual, the federal water managers use

100 Atmospheric rivers are a flowing corridor of concentrated water vapor in the atmosphere that can contribute to
significant rainfall or snow upon landfall. According to NOAA, atmospheric rivers on average contribute between 30%
and 50% of annual precipitation on the along the West Coast of the continental United States. For more information,
see NOAA, What Are Atmospheric Rivers?,” at https://www.noaa.gov/stories/what-are-atmospheric-rivers.
101 In addition to expressing interest in using forecasts, Congress has supported the expansion of the collection and use
of observed data in informing reservoir operations and other flood and drought risk preparedness activities in some
basins. For example, in 2014, Congress authorized actions to improve soil moisture and snowpack monitoring in the
Upper Missouri River Basin (P.L. 113-121, §4003(a)).
102 Ongoing FIRO research efforts are underway for Prado Dam, CA; the Yuba-Feather River System, CA; and Howard
Hanson Dam, WA. The Lake Mendocino FIRO research effort featured involvement by NOAA, Reclamation, USACE,
state and local agencies, and academics.
103 Jay Jasperse et al., Lake Mendocino: Forecast Informed Reservoir Operations Final Viability Assessment,
December 2020, at https://escholarship.org/uc/item/3b63q04n. The report states, “Because each watershed and location
is unique, the analysis, results, and conclusions of the [final viability assessment] are only applicable to Lake
Mendocino.”
104 Although the updated Folsom Dam Water Control Manual has some FIRO characteristics, USACE indicates that
FIRO research was not explicitly used in the revision to the manual (personal communication from USACE staff to
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continuous five-day forecasts available for that region of California to identify plausible flows
into the reservoir to assess operational release requirements.
How widely and how quickly benefits of forecast-informed operations may assist in drought
preparedness remains an area of active interest and ongoing research. Current federal research
efforts focus on understanding the influence of site characteristics and other factors on the
forecasting of atmospheric rivers, which may help in identifying opportunities and limitations of
applying FIRO to other reservoir sites. Enhanced soil moisture and snowpack monitoring also
may inform adjustments in reservoir operations and other drought responses, especially for
regions with water regimes less influenced by atmospheric rivers.105
Drought Flexibilities and the Endangered Species Act
Some federal and nonfederal water infrastructure projects in the United States operate under
requirements of the Endangered Species Act (ESA; 16 U.S.C. §§1531-1544).106 Operational plans
and ESA regulations often result in water projects maintaining a certain level of water in the
ecosystem, such as in-stream flows below a dam, for species listed as threatened or endangered
under the ESA. Under drought conditions, this practice can lead to disagreements among
stakeholders vying for scarce water supplies. Water projects that might affect listed species or
their habitat undergo consultation under Section 7 of the ESA. The consultation results in a
biological opinion (BiOp), issued by either the U.S. Fish and Wildlife Service (FWS) or the
National Marine Fisheries Service (NMFS), that governs project operations. Some project BiOps
include policy mechanisms to maximize water supplies for users during drought while continuing
to conserve listed species. These mechanisms include the use of adaptive management (AM),
real-time management of water supplies, artificial propagation of listed species (e.g., hatcheries),
and habitat restoration.
Projects use AM to provide flexibility during drought conditions. AM is the process of
incorporating new scientific and programmatic information into the implementation of a project
or plan to ensure the activity’s goals are reached efficiently. AM promotes adaptable
decisionmaking that modifies existing activities and/or creates new activities if new
circumstances arise (e.g., new scientific information) or projects are not meeting their goals.
Under drought conditions, AM provisions in a project’s BiOp might allow federal agencies to
address the conservation needs of a listed species while still accomplishing project purposes. In
some cases, the operations of water infrastructure have used AM to account for changes in
environmental conditions that were not contemplated in a BiOp. In these cases, the agency may
seek concurrence from either FWS or NMFS to perform temporary modifications to the BiOp’s
implementation.
Some BiOps allow for “real-time” management (i.e., management based on changing conditions)
of water projects under certain circumstances, including drought, to maximize water supplies for
users or address immediate threats to species. This approach allows managers to alter project
operations in real time to respond to changing conditions. For example, pursuant to the 2019
BiOp for the coordinated operations of the Central Valley Project (CVP) and the State Water

CRS staff, July 8, 2021).
105 For an example, see footnote 101.
106 For more information on the Endangered Species Act (ESA; 16 U.S.C. §§1531-1544), see CRS Report R46677, The
Endangered Species Act: Overview and Implementation, by Pervaze A. Sheikh, Erin H. Ward, and R. Eliot Crafton;
and CRS Report R46867, Endangered Species Act (ESA) Section 7 Consultation and Infrastructure Projects, by Erin
H. Ward, R. Eliot Crafton, and Pervaze A. Sheikh.
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Project in California, project pumping operations may adhere to certain preestablished levels,
unless findings from real-time monitoring of threatened Delta smelt trigger changes that aim to
conserve the species. Congress authorized this approach for CVP operations under Section 4001
of the WIIN Act. At the time, supporters generally endorsed the provisions as short-term
measures to alleviate the effects of the ongoing drought in California on users.107
Other Drought Authorities: Support for Nonfederal Drought
Planning and Projects
In addition to the aforementioned federal activities and programs, multiple federal agencies have
programmatic authorities to support non-federally led projects related to drought. Some of these
authorities are discussed below.
Bureau of Reclamation Drought Response Program and Other Authorities108
In recent years, Congress has enacted multiple new authorities for Reclamation to support
nonfederal efforts to conserve water. In contrast to Reclamation’s traditional activities, there is
typically no federal ownership role associated with projects supported by these authorities. As
with Reclamation’s other authorities, the new authorities mostly limit activities to the 17
reclamation states defined in statute.109 Reclamation combines funding for its programs
promoting water conservation into a single program—the WaterSMART (Sustain and Manage
American Resources for Tomorrow) program. Programs under WaterSMART with direct ties to
drought are discussed below.
The Drought Response Program (DRP) is Reclamation’s only program specifically dedicated to
addressing drought. The DRP assists water managers develop and implement comprehensive
drought plans and related projects that build long-term drought resiliency. Specific sub-program
areas of the DRP include Contingency Planning, Resiliency Projects, and Emergency Response
Actions. In an effort to incentivize advanced planning and mitigation, Reclamation directs the
majority of DRP funding to the first two sub-program areas. According to Reclamation, the
bureau funds DRP planning and resiliency projects sequentially, when possible. First, it funds
planning for communities to learn how droughts will affect them, as well as to scope potential
projects to reduce the impacts of the next drought. Subsequently, it prioritizes grant funding for
resiliency projects identified through the planning process. Generally, Reclamation supports
resiliency projects that attempt to either (1) increase the reliability of water supplies by providing
additional alternatives during drought (e.g., constructing new infrastructure, such as intakes or
groundwater banking facilities) or (2) improve water management by providing entities with tools
and decision support (e.g., improved modeling, access to water markets). Both contingency
planning and resiliency efforts include a 50/50 cost share with local sponsors.
Reclamation reserves a small amount of DRP funding for emergency response actions, as
authorized in the Reclamation States Drought Relief Act of 1991 (P.L. 102-250). Eligible projects
include temporary construction activities (e.g., temporary pipes and pumps) and other actions
authorized under Title I of the act (e.g., water purchases, use of Reclamation facilities to convey

107 For additional information about these provisions, see CRS Report R44986, Water Infrastructure Improvements for
the Nation (WIIN) Act: Bureau of Reclamation and California Water Provisions, by Charles V. Stern, Pervaze A.
Sheikh, and Nicole T. Carter.
108 For more information on these programs, contact Charles Stern, Specialist in Natural Resources Policy.
109 43 U.S.C. §391.
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and store water) that can be completed within a year. Reclamation conducts emergency response
actions through contracts rather than through the provision of financial assistance, and approval
of these actions is subject to a number of other requirements, such as a state or tribal drought
declaration.110
Other WaterSMART programs also have the potential to lessen drought impacts, including by
supporting some means of alternative water supplies, increased efficiency, and/or water resources
conservation. For example, the Title XVI Program provides cost-shared financial assistance for
authorized nonfederal studies and construction projects that provide supplemental water supplies
by recycling or reusing agricultural drainage water, wastewater, brackish surface and
groundwater, and other sources of contaminated water. Similarly, Reclamation’s Desalination
Program provides federal financial support for selected nonfederal desalination projects that
Congress has approved. Although project selection processes for both programs prioritize drought
resiliency (among other criteria), they do not formally prioritize funding for drought-stricken
areas. Generally, projects under the Title XVI Program and the Desalination Program take years
to construct.
Several WaterSMART programs promote water conservation and related efforts and therefore
provide benefits that may increase drought resiliency. For instance, WaterSMART Grants provide
cost-shared federal funding for projects in multiple categories, including water and energy
efficiency grants, small-scale water efficiency grants, and water marketing strategy grants.
Separately, Reclamation’s Basin Study Program supports efforts to address imbalances between
water supply and demand in western river basins through applied science tools, guidance, and
information to support water management planning. Reclamation’s Cooperative Watershed
Management Program provides funding to watershed groups to encourage stakeholders to find
local solutions to water management needs. Most of these programs require some form of cost
sharing from nonfederal sponsors to leverage federal funding, and most include caps on the
amount of federal assistance.111
Congress also has authorized targeted grant programs to combat drought and add system water
through conservation efforts in drought-stricken river basins.112 For example, in the Lower
Colorado River Basin,113 the Pilot System Conservation Program (part of the Lower Basin’s
Drought Contingency Plan) provides funding for voluntary conservation projects and reductions
of water use; water conserved from these projects is applied toward storage in Lake Mead, one of
the basin’s two large storage reservoirs. Congress authorized this funding in the Energy and Water
Development and Related Agencies Appropriations Act, 2015 (P.L. 113-235) and has since
stipulated that this authorization is a subset of the aforementioned WaterSMART Grants
authorization under Section 9504(e) of the SECURE Water Act.

110 This requirement applies only to entities without an approved DCP. For more information on emergency drought
assistance requirements, see Reclamation, “Request for Emergency Drought Assistance Checklist,” WTR 10-01,
Appendix C, at https://www.usbr.gov/recman/wtr/wtr10-01-AppC.pdf.
111 For more information on these and other Reclamation programs supporting nonfederal water supplies and planning,
see Reclamation, “WaterSMART,” at https://www.usbr.gov/watersmart/.
112 System water refers to water that is provided to increase water supplies as a whole, without being directed toward
additional consumptive use for specific contractors or water users.
113 For more information about ongoing drought in the Colorado River Basin and federal response efforts, see CRS
Report R45546, Management of the Colorado River: Water Allocations, Drought, and the Federal Role, by Charles V.
Stern and Pervaze A. Sheikh.
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USDA Programs and Authorities
Rural Utilities Service114
USDA’s Rural Utilities Service (RUS) provides grants and loans for rural community and
household water systems. Some of these programs are tailored for emergency situations, whereas
others may prioritize loans and grants for rural communities and households facing drought-
related declines in water quantity or quality. For RUS programs, rural communities are often
defined as those with populations of fewer than 10,000 residents. The RUS programs that may
assist in addressing drought-related rural water issues include the following:
 Water and Waste Disposal Grants and Loans.115 The Rural Water and Waste
Disposal Program supports construction and improvements to rural community
water systems (i.e., drinking water, sanitary sewage, solid waste disposal, and
storm drainage facilities). Although most of these funds are provided to assist
with rural community water and waste systems broadly, systems affected by
drought may receive a priority.
 Emergency and Imminent Community Water Assistance Grants.116 This
program provides grants specifically to rural water systems experiencing an
emergency resulting from a significant decline in the quantity or quality of
drinking water. A federal disaster declaration is not required to participate in this
program.
 Rural Decentralized Water Systems Grant Program.117 This program provides
grants to nonprofit organizations, which provide loans or grants to eligible
individuals for refurbishing household water-well systems in rural areas. Eligible
rural areas include rural areas or towns with populations of less than 50,000
residents. Sub-loans or sub-grants are to be made to individuals with low or
moderate incomes. Some of this program’s funds may be used to assist drought-
affected households.
Natural Resources Conservation Service118
USDA’s Natural Resources Conservation Service (NRCS) provides assistance for watershed
activities under four closely related authorities. Most of these programs pay a percentage of the
cost to install infrastructure or correct impairments, and they require a local project sponsor. The
programs are permanently authorized but subject to appropriations. Applications may be filed at
any local or state NRCS office.119

114 For more information about the Rural Utilities Service, contact Lisa Benson, Analyst in Agricultural Policy.
115 For additional information, see USDA, Rural Development, “Water and Waste Disposal Loan and Grant Program,”
at https://www.rd.usda.gov/programs-services/water-waste-disposal-loan-grant-program.
116 For additional information, see USDA, Rural Development, “Emergency Community Water Assistance Grants,” at
https://www.rd.usda.gov/programs-services/emergency-community-water-assistance-grants.
117 For additional information, see USDA, Rural Development, “Rural Decentralized Water Systems Grant Program,”
at https://www.rd.usda.gov/programs-services/rural-decentralized-water-systems-grant.
118 For more information on NRCS programs, contact Megan Stubbs, Specialist in Agricultural Conservation and
Natural Resources Policy.
119 To find a local NRCS office, see https://offices.sc.egov.usda.gov/locator/app.
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 Watershed and Flood Prevention Operations (WFPO) Program. The WFPO
program consists of two authorities—the Watershed Protection and Flood
Prevention Act of 1954 (P.L. 83-566) and the Flood Control Act of 1944 (P.L. 78-
534). These acts authorize NRCS to provide technical and financial assistance to
state and local organizations to plan and install measures to prevent erosion,
sedimentation, and flood damage and to conserve, develop, and use land and
water resources.120
 Watershed Rehabilitation Program. The Watershed Rehabilitation Program
provides technical and financial assistance for planning, design, and
implementation to rehabilitate aging watershed dam projects (including
upgrading or removing dams) in communities to address health and safety
concerns. Only dams constructed under the WFPO program are eligible.121
 Emergency Watershed Protection (EWP) Program. The EWP program assists
local project sponsors in implementing emergency recovery measures for runoff
retardation and erosion prevention to relieve imminent hazards to life and
property created by natural disasters, including drought. For example, the
program can be used to reseed drought-stricken areas that would be prone to
erosion and could pose a threat to life or property.122
USACE Emergency Water Supplies123
In 1974, Congress provided USACE with authority (33 U.S.C. 701n) to assist with emergency
water supplies (e.g., bulk or bottled water) and their transport when state resources are exceeded
and a public health threat is imminent.124 USACE provides assistance only to meet any minimum
public health and welfare requirements that cannot be met in the immediate future by state or
local actions or through reasonable conservation measures. USACE assistance may include
various activities, some of which must be reimbursed (i.e., 100% nonfederal expenses) and some
at full federal expense (i.e., 100% federal), as follows:
 Purchase or acquisition of the water and the storage facility at the terminal point
and permanent water facilities are reimbursable expenses (i.e., 100% nonfederal)
 USACE well construction costs (i.e., 100% nonfederal)
 Water transport costs are nonreimbursable expenses (i.e., 100% federal)
A governor, a governor’s representative, or the governing body of a tribe must make a written
request for assistance to USACE. The USACE Director of Civil Works or the Assistant Secretary

120 For additional information on the Watershed and Flood Prevention Operations Program, see CRS Report R46471,
Federally Supported Projects and Programs for Wastewater, Drinking Water, and Water Supply Infrastructure,
coordinated by Jonathan L. Ramseur.
121 The Watershed Rehabilitation Program is authorized under Section 313 of the Grain Standards and Warehouse
Improvement Act of 2000 (P.L. 106-472) and Section 14 of the Watershed Protection and Flood Prevention Act, as
amended (16 U.S.C. §1012). For more information, see CRS Report R46471, Federally Supported Projects and
Programs for Wastewater, Drinking Water, and Water Supply Infrastructure, coordinated by Jonathan L. Ramseur.
122 The Emergency Watershed Protection Program is authorized under Title IV of the Agricultural Credit Act of 1978
(P.L. 95-334; 16 U.S.C. §2203) and 33 U.S.C. §701b-1. For additional information on the program, see CRS Report
R42854, Emergency Assistance for Agricultural Land Rehabilitation, by Megan Stubbs.
123 For more information on these authorities, contact Nicole Carter, Specialist in Natural Resources Policy.
124 This authority cannot be used for the provision of water for livestock, irrigation, recreation, or commercial/industrial
use. Eligible entities are limited to drought-distressed political subdivisions, farmers, and ranchers.
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of the Army (Civil Works) makes the determination that an area has an inadequate water supply
that is causing, or is likely to cause, a substantial threat to the health and welfare of the area’s
inhabitants. Funding for actions pursuant to this authority is provided through the USACE Flood
Control and Coastal Emergencies Account. In most years, USACE does not receive requests to
use this authority; it has used the authority most often to assist tribes with emergency drinking
water issues. USACE also has the authority to contract for limited quantities of water (if
available) from its reservoirs for municipal and industrial purposes.
U.S. Environmental Protection Agency Programs125
Improving public water system resilience to droughts and other events that may disrupt the
provision of a safe and reliable water supply has been a focus of congressional attention.
Congress has established programs administered by EPA that provide financial assistance to
public water systems for projects that help ensure the provision of a safe and reliable water
supply. Further, several provisions of the Safe Drinking Water Act (SDWA; 42 U.S.C. §300j-12)
promote water systems’ preparedness for, and resilience to, events that may disrupt water service
(e.g., natural hazards, malevolent acts).126
Drinking Water State Revolving Fund127
In 1996, Congress established the Drinking Water State Revolving Fund (DWSRF) program to
provide financial assistance to public water systems for infrastructure projects needed to comply
with federal drinking water regulations and protect public health.128 Projects that aim to increase
water system drought resilience through the development of a new or alternative drinking water
source(s) and through the construction or rehabilitation of water storage are eligible for DWSRF
financial assistance.129
Congress annually appropriates DWSRF program funding, which EPA uses to make annual grants
to states to capitalize their drinking water state revolving loan funds. Every year, each state must
match 20% of its annual capitalization grant and develop an intended-use plan for the allotted
funds. The SDWA requires states to give funding priority to projects that address the most serious
human health risks; are necessary to ensure regulatory compliance; and assist systems most in
need on a per household basis, according to state affordability criteria. Depending on the
applicants’ project types and the state’s individual circumstances, a state may prioritize DWSRF
assistance for drought resilience projects, such as alternative water projects to replace diminished
or contaminated water sources. The primary type of DWSRF financial assistance are low-interest-

125 For more information on these programs, contact Elena Humphreys, Analyst in Environmental Policy.
126 42 U.S.C. §§300f et seq. For a discussion of Safe Drinking Water Act (SDWA; 42 U.S.C. §300j-12) risk and
resilience assessments and emergency response planning requirements, see CRS In Focus IF11777, Safe Drinking
Water Act (SDWA): Water System Security and Resilience Provisions, by Elena H. Humphreys.
127 For more information about the Drinking Water State Revolving Fund (DWSRF), see CRS Report R45304,
Drinking Water State Revolving Fund (DWSRF): Overview, Issues, and Legislation, by Mary Tiemann.
128 The Safe Drinking Water Act Amendments of 1996 (P.L. 104-182 P.L. 104-182), Section 130, added the DWSRF
provisions (§1452) to the SDWA. The Clean Water Act (CWA) authorized complementary financial assistance
programs to help publicly owned treatment works achieve CWA compliance and other statutory purposes. The Clean
Water State Revolving Fund (CWSRF) provides financial assistance for infrastructure projects to publicly owned
treatment works and other eligible recipients (33 U.S.C. §§1381-1387). Water recycling and/or reuse projects and other
projects eligible for CWSRF financial assistance may reduce the use of potable water for irrigation or other activities
and may increase drinking water supplies. The key purpose of DWSRF financial assistance is to support projects that
the Environmental Protection Agency (EPA) has determined through guidance will facilitate compliance with SDWA.
129 EPA, Drinking Water State Revolving Fund Eligibility Handbook, EPA 816-B-17-001, June 2017.
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rate loans. SDWA Section 1452 authorizes states to provide additional subsidization (including
forgiveness of principal) to disadvantaged communities.130 The federal capitalization grants,
together with state funds (e.g., state match, loan repayments, leveraged bonds, and other state
sources), are intended to build a sustainable source of drinking water infrastructure funding.
Water Infrastructure Finance and Innovation Act131
The Water Resources Reform and Development Act of 2014 (P.L. 113-121) authorized the Water
Infrastructure Finance and Innovation Act (WIFIA) program to promote development of and
private investment in water infrastructure projects.132 WIFIA authorized EPA and USACE to
provide credit assistance in the form of secured or direct loans for a range of water infrastructure
projects.
The range of eligible projects for the EPA-administered WIFIA program is broader than for the
DWSRF program or for the analogous Clean Water State Revolving Fund program, which
provides financial assistance for publicly owned treatment works. WIFIA-eligible drinking water
projects include those projects eligible for DWSRF financial assistance and other projects that
may support drought resilience, such as through the following activities:
 Desalination
 Aquifer recharge or development of alternative water supplies to reduce aquifer
depletion
 Water recycling and/or reuse
 Mitigation, prevention, or reduction of the effects of drought
Entities eligible for WIFIA assistance include (1) state infrastructure financing authorities; (2)
corporations; (3) partnerships; (4) joint ventures; (5) trusts; and (6) federal, state, local, or tribal
governments or instrumentalities. WIFIA establishes broad selection criteria that EPA uses to rank
projects, including a project’s national or regional significance with respect to economic and
public benefits, creditworthiness, and readiness.
Each year that Congress appropriates funds to cover subsidies for WIFIA loans, EPA publishes a
Notice of Funding Availability (NOFA) to provide interested entities with WIFIA application
information. In each NOFA, EPA identifies considerations for project prioritization (e.g.,
repairing aging infrastructure). For FY2021, the WIFIA selection criteria include projects that
“protect the nation’s water infrastructure from the impacts of climate change” and new and
innovative projects such as “the development of alternative sources of drinking water through, for
example, desalination, aquifer recharge or water recycling, and resource recovery.”133

130 SDWA §1452(d); 42 U.S.C. §300j-12(d) authorized states to provide additional subsidization to disadvantaged
communities. Disadvantaged community is defined as the service area of a public water system that meets affordability
criteria developed by the state.
131 For more information about the Water Infrastructure Finance and Innovation Act (WIFIA) program, see CRS Report
R43315, Water Infrastructure Financing: The Water Infrastructure Finance and Innovation Act (WIFIA) Program, by
Jonathan L. Ramseur, Mary Tiemann, and Elena H. Humphreys.
132 33 U.S.C. §§3901-3914.
133 EPA, “Notification of Funding for Credit Assistance Under the Water Infrastructure Finance and Innovation Act
(WIFIA) Program,” 86 Federal Register 22616, April 29, 2021.
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WaterSense
Programs that identify and promote the use of water-efficient products and/or services aim to
lessen the effects of drought, though not by providing financial assistance. WaterSense is a
voluntary labeling program that EPA created to encourage the development and use of water-
efficient products and services.134 Through WaterSense, EPA develops water-efficiency
specifications for products, certain services, and homes; licenses third-party certification bodies;
and maintains a registry of WaterSense-labeled products and certified services. The 115th
Congress authorized and expanded WaterSense in Section 4306 of America’s Water Infrastructure
Act of 2018 (P.L. 115-270).135
EPA has issued WaterSense specifications for categories of services and a variety of products,
including residential toilets, showerheads, bathroom faucets, commercial toilets, urinals,
irrigation controllers, and spray sprinkler bodies. To obtain certification to use a WaterSense
label, manufacturers must develop products that meet EPA specifications. EPA states that a water-
efficient product should generally (1) reduce water use by at least 20% from federally mandated
water-use conservation standards and (2) function at least as well as regular models. For products
without federal standards, such as irrigation equipment, WaterSense certifications are based on
calculations of average efficiency. The use of water-efficient products may reduce demand for
water, helping communities improve drought resilience. EPA estimates the program saved 5.3
trillion gallons of water from 2006 to 2020.136
Congressional Proposals in the 117th Congress
Recent drought events have increased the profile of drought and have led to congressional and
administrative proposals to prepare for and respond to drought’s effects. Congressional interest in
drought may include new and amended authorities for drought planning and response, emergency
appropriations and reprogramming that could enhance existing drought-related activities, and
oversight of ongoing federal efforts to address the impacts of drought. Congress also may
consider additional funding and direction for existing authorities. Some current legislative
proposals are discussed below.
New and Amended Drought Authorities
Monitoring and Research
Some legislation introduced in the 117th Congress would direct agencies to work together on
aspects of water management that could affect drought preparedness and response. For instance,
provisions in H.R. 1438 and S. 558 would establish an interagency coordinating committee on
water management, with members from NOAA, USACE, USDA, DOI, FEMA, the National
Science Foundation, the Department of Energy, EPA, the Office of Science and Technology
Policy, the Council on Environmental Quality, and others, as appropriate. The committee’s
purpose would be to “ensure” the federal government engages in water-related matters, including
water storage and supplies, water infrastructure, and water forecasting, among other topics, where
agencies have joint or overlapping responsibilities.

134 EPA established WaterSense in 2006.
135 42 U.S.C. §6294b.
136 EPA, WaterSense 2020 Accomplishments Report, EPA-832-F-21-024, June 2021.
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Provisions under H.R. 1438 and S. 558 would direct NOAA to collect and disseminate data and
information regarding certain drought factors. For instance, one provision would direct NOAA to
establish a national integrated flood information system with data on streamflow, reservoir release
and diversion, precipitation, soil moisture, snow-water equivalent, land cover, and evaporative
demand. The provision would require NOAA to leverage the efforts of other groups, such as
NIDIS and USGS. Other provisions would direct the agency to improve precipitation frequency
estimates (similar to provisions in H.R. 1437) and to conduct a gap analysis in the availability of
snow-related data, in consultation with USDA, DOI, and USACE. Finally, these bills (as well as
H.R. 2760 and S. 1282) would direct NOAA to identify and support research to establish a
“consistent federal set of forward-looking, long-term meteorological information that models
future extreme weather events,” including drought, for use by other federal and nonfederal
entities in their planning efforts.
Other proposed legislation would direct agencies to study the effects of drought in targeted areas.
For example, H.R. 3764 would direct NOAA to report to Congress on the impacts of drought,
among other phenomena, on ocean, coastal, and Great Lakes ecosystems.
USDA Drought Support Programs
Recent congressional proposals for agricultural loss assistance have centered on continuing or
expanding ad hoc assistance provided through supplemental appropriations. Over the past 20
years, Congress has authorized permanent disaster assistance programs and expanded federal crop
insurance and NAP policies to reduce the need for ad hoc disaster assistance (see “USDA
Drought Support Programs,” above). In 2018, Congress funded ad hoc assistance for agricultural
losses for the first time in over a decade. The Bipartisan Budget Act of 2018 (P.L. 115-123)
created the Wildfires and Hurricanes Indemnity Program (currently referred to as WHIP+), which
made available $2.36 billion for payments to farmers and ranchers with crop, tree, bush, and vine
losses as a result of a wildfire or hurricane occurring in 2017.137 Subsequent appropriations
expanded WHIP+ to include losses from other natural disaster events, including drought in
counties with a U.S. Drought Monitor classification of D3 (extreme) or D4 (exceptional) in
calendar years 2018 and 2019.138 On July 27, 2021, the House Agriculture Committee
unanimously reported H.R. 267. As amended, the bill would extend WHIP+ to cover losses in
2020 and 2021, increase payments for selected crops, add qualifying disaster events, and
authorize up to $8.5 billion for subsequent appropriations. Under the bill, qualifying losses related
to drought would expand to include counties with a USDA secretarial disaster designation for
drought (i.e., D2 for eight consecutive weeks according to the U.S. Drought Monitor). WHIP+
also would expand coverage to other drought-related losses, such as losses from extreme heat.
Federal Facilities: Western Water Supplies and Reclamation Programs
Several legislative proposals would reauthorize and/or amend existing authorities related to
Reclamation and drought in the West. Several proposals have focused on extending or amending
Reclamation provisions that Congress enacted in the WIIN Act to address drought. Some bills
(e.g., H.R. 737 and H.R. 1563) would extend the WIIN Act’s California water provisions, which

137 For more information on WHIP+, see CRS In Focus IF11539, Wildfires and Hurricanes Indemnity Program
(WHIP), by Megan Stubbs.
138 The Additional Supplemental Appropriations for Disaster Relief Act of 2019 (P.L. 116-20) added $3 billion in
funding for losses in 2018 and 2019. Section 791 of Division B of the FY2020 Further Consolidated Appropriations
Act (P.L. 116-94) further amended the program by repurposing unobligated expiring WHIP+ funding, expanding
eligibility, and adding program requirements.
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aimed to provide operational flexibility during drought for the nation’s largest water project, the
CVP (see “Drought Flexibilities and the Endangered Species Act, above”). Other legislation, such
as H.R. 4018, also would renew the WIIN Act CVP operational provisions but would go farther
by explicitly directing the Secretary of the Interior to maximize the CVP’s operations by
approving any projects that would provide additional water supplies and requiring operations
pursuant to the 2019 CVP BiOps,139 among other requirements.
Several bills would extend WIIN Act authorities to study and fund new water storage projects in
the West. In addition to extensions of the aforementioned operational proposals in the WIIN Act,
H.R. 737 and H.R. 1563 would extend WIIN Act provisions authorizing additional storage
projects throughout the West through 2031 and 2028, respectively. Other legislation would focus
exclusively on supporting more water reuse and recycling and desalination projects. H.R. 1015
would increase authorized funding for Reclamation’s Title XVI water reuse and recycling
projects under the WIIN Act,140 with priority given to regional projects that improve water supply
reliability and flexibility and provide ecosystem benefits, among other criteria. S. 2334 also aims
to support water reuse and recycling projects but would do so with a focus on additional support
for “large-scale” water recycling projects (i.e., projects with costs of more than $500 million) by
raising the federal cost-share caps for these projects. A separate bill, H.R. 4712, would authorize
increased Reclamation support for desalination project development.
Some legislation would address multiple western water priorities, including water storage and
water conservation. For example, H.R. 3404 would authorize funding in several different areas
with the goal of increasing drought resiliency, including new funding for storage, water reuse and
recycling, and desalination, as well as investments in improved technology and data, ecosystem
restoration and protection, water job training, and other areas. S. 953 would authorize new
funding for infrastructure development for water reuse and recycling and desalination projects
and for ecosystem restoration and protection to support biodiversity in droughts and drought
preparation for fisheries, among other priorities.
Emergency Appropriations and Reprogramming for Drought
In the past, supplemental appropriations legislation has provided funding to address drought
concerns. In the 117th Congress, nationwide and regional drought-related provisions are among
the items included in Division J of H.R. 3684, the Infrastructure Investment and Jobs Act (IIJA),
as passed by the Senate in August 2021. IIJA would provide emergency appropriations for a
number of drought-related provisions, such as the following:
 $300 million over five years to Reclamation for Colorado River Basin DCP
funding
 $80 million over five years to NOAA for high-performance computing to
improve climate and weather modeling capabilities, related to drought, flood and
wildfire prediction, detection, and forecasting, plus $492 million over five years
to NOAA for coastal and inland flood and inundation mapping and forecasting
and for next-generation water modeling activities, including modernized
precipitation frequency and maximum studies

139 For more information, see CRS Report R45342, Central Valley Project: Issues and Legislation, by Charles V. Stern
and Pervaze A. Sheikh.
140 For more information about these projects, including a list of projects currently eligible for funding, see
Reclamation, “WIIN Eligible Projects,” at https://www.usbr.gov/watersmart/title/wiin.html.
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 $25 million over three years to NOAA for data acquisition and $1 million over
four years for the study of a soil moisture and snowpack monitoring pilot
program in the Upper Missouri River Basin
 $40 million over five years to USACE for Missouri River Basin soil moisture
and snowpack monitoring
 $918 million over five years for NRCS watershed programs, including the
WFPO, Watershed Rehabilitation, and EWP Programs
 $1 billion over five years for Reclamation’s Title XVI program and $250 million
over five years for Reclamation contributions to eligible desalination projects, as
well as $400 million for Reclamation WaterSMART water and energy efficiency
grants.
Some agencies also have reprogrammed previous appropriations and/or transferred funding
internally to address drought-related priorities. For example, in February 2021, Reclamation
announced $15 million in funding for drought relief at the federal Klamath Project in Oregon; this
funding came from a combination of base spending, internal transfers, and the allocation of
additional funding from Congress. In July 2021, Reclamation notified Congress of its intent to
reprogram $100 million in prior-year appropriations toward various drought-related projects in
the western United States.141
Annual appropriations also may include emergency funding for drought-related losses. For
example, the Senate-reported Agriculture appropriations bill (S. 2599, §773) includes $7.03
billion in emergency spending for WHIP+ for 2020 and 2021 losses. The bill stipulates that losses
related to drought must have occurred in counties with a D3 (extreme) or higher classification
according to the U.S. Drought Monitor. Of the $7.03 billion, $750 million would be specifically
for livestock losses in 2021 due to drought or wildfires. Funding to extend WHIP+ was not
included in the House-passed FY2022 Agriculture appropriations bill (H.R. 4502, Division B).

Author Information

Charles V. Stern, Coordinator
Elena H. Humphreys
Specialist in Natural Resources Policy
Analyst in Environmental Policy

Eva Lipiec, Coordinator
Pervaze A. Sheikh
Analyst in Natural Resources Policy
Specialist in Natural Resources Policy

Lisa S. Benson
Megan Stubbs
Analyst in Agricultural Policy
Specialist in Agricultural Conservation and Natural

Resources Policy

Nicole T. Carter

Specialist in Natural Resources Policy

141 Letter from Rachel S. Taylor, Assistant Secretary of the Interior for Policy, Management, and Budget, to Honorable
Marcy Kaptur, Chairwoman, Subcommittee on Energy and Water Development, July 23, 2021.
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Disclaimer
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under the direction of Congress. Information in a CRS Report should not be relied upon for purposes other
than public understanding of information that has been provided by CRS to Members of Congress in
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