EPA and the Army Corps’ Proposed Rule to
Define “Waters of the United States”
Claudia Copeland
Specialist in Resources and Environmental Policy
April 21, 2014
Congressional Research Service
7-5700
www.crs.gov
R43455

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”

Summary
On March 25, 2014, the Environmental Protection Agency (EPA) and the U.S. Army Corps of
Engineers (Corps) jointly proposed a rule defining the scope of waters protected under the Clean
Water Act (CWA). The proposal would revise regulations that have been in place for more than
25 years. Revisions are proposed in light of 2001 and 2006 Supreme Court rulings that interpreted
the regulatory scope of the CWA more narrowly than previously, but created uncertainty about the
precise effect of the Court’s decisions.
In 2011, EPA and the Corps proposed guidance on policies for determining CWA jurisdiction to
replace guidance issued in 2003 and 2008; all were intended to lessen confusion over the Court’s
rulings. The 2011 proposed guidance was extremely controversial, with some contending that it
represented an overreach beyond the agencies’ statutory authority. Most environmental groups
welcomed the proposed guidance, although some would have preferred a stronger document. The
2014 proposed rule would replace the existing 2003 and 2008 guidance, which remains in effect
because the 2011 proposed guidance was not finalized.
According to the agencies, the proposed rule would revise the existing administrative definition
of “waters of the United States” consistent with legal rulings and science concerning the
interconnectedness of tributaries, wetlands, and other waters and effects of these connections on
the chemical, physical, and biological integrity of downstream waters. Waters that are
“jurisdictional” are subject to the multiple regulatory requirements of the CWA. Non-
jurisdictional waters do not have the federal legal protection of those requirements.
This report describes the proposed rule and includes a table comparing the existing regulatory
language that defines “waters of the United States” with the proposal. The proposed rule is
particularly focused on clarifying the regulatory status of waters located in isolated places in a
landscape. It does not modify some categories of waters that currently are jurisdictional by rule
(traditional navigable waters, interstate waters and wetlands, the territorial seas, and
impoundments). Proposed changes would increase the asserted scope of CWA jurisdiction, in part
as a result of expressly declaring some types of waters categorically jurisdictional (such as all
waters adjacent to a jurisdictional water), and also by application of new definitions, which give
larger regulatory context to some types of waters, such as tributaries.
Beyond the categories of waters that would be categorically jurisdictional under the proposal is a
category sometimes referred to as “other waters.” The regulatory term “other waters” applies to
wetlands and non-wetland waters such as prairie potholes that are not considered traditionally
navigable or meet other of the proposed rule’s jurisdictional definitions. Much of the controversy
since the Supreme Court rulings has focused on the degree to which “other waters” are
jurisdictional. According to the agencies’ analyses, 17% of these “other waters” would be
categorically jurisdictional under changes in the proposal. It also lists waters and features that
would not be jurisdictional, such as prior converted cropland and certain ditches. It makes no
change to existing statutory and regulatory permit exclusions, such as exemptions for normal
farming and ranching activities.
The agencies believe that the proposal does not exceed the CWA’s coverage or protect new types
of waters that have not been protected historically. While it would enlarge jurisdiction beyond
that under the existing EPA-Corps guidance, they believe that it would not enlarge jurisdiction
beyond what is consistent with the Supreme Court’s narrow reading of jurisdiction. Others may
Congressional Research Service

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”

disagree. Overall, the agencies estimate that approximately 3% of U.S. waters will additionally be
subject to CWA jurisdiction as a result of the proposed rule (including additional “other waters”),
compared with current field practice. EPA and the Corps estimate that costs of the proposal, from
additional permit application expenses, for example, range from $162 million to $279 million
annually. Benefits, including the value of ecosystem services such as flood protection, are
estimated to range from $318 million to $514 million per year. They acknowledge uncertainties
and limitations in these estimates.

Congressional Research Service

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”

Contents
Introduction ...................................................................................................................................... 1
The CWA and the Proposed Rule .................................................................................................... 2
“Other Waters” .......................................................................................................................... 4
Exclusions and Definitions ........................................................................................................ 5
Impacts of the Proposed Rule .......................................................................................................... 5
Conclusion ....................................................................................................................................... 7

Tables
Table 1. Comparison of “Definition of Waters of the United States” Regulatory Language ........... 9

Contacts
Author Contact Information........................................................................................................... 18

Congressional Research Service

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”

Introduction
On March 25, 2014, the Environmental Protection Agency (EPA) and the U.S. Army Corps of
Engineers (Corps) jointly proposed a rule defining the scope of waters protected under the Clean
Water Act (CWA). The proposed rule would revise regulations that have been in place for more
than 25 years.1 Revisions are proposed in light of Supreme Court rulings in 2001 and 2006 that
interpreted the regulatory scope of the CWA more narrowly than previously, but created
uncertainty about the precise effect of the Court’s decisions.2
In April 2011, EPA and the Corps proposed guidance on policies for determining CWA
jurisdiction to replace guidance previously issued in 2003 and 2008; all were intended to lessen
confusion over the Court’s rulings for the regulated community, regulators, and the general
public. The guidance documents sought to identify, in light of the Court’s rulings, categories of
waters that remain jurisdictional, categories not jurisdictional, and categories that require a case-
specific analysis to determine if CWA jurisdiction applies. The 2011 proposed guidance identified
similar categories as in the 2003 and 2008 documents, but it would have narrowed categories that
require case-specific analysis in favor of asserting jurisdiction categorically for some types of
waters. The 2014 proposed rule would replace the existing 2003 and 2008 guidance, which
remains in effect because the 2011 proposed guidance was not finalized.3
The 2011 proposed guidance was extremely controversial, especially with groups representing
property owners, land developers, and the agriculture sector, who contended that it represented a
massive federal overreach beyond the agencies’ statutory authority. Most state and local officials
were supportive of clarifying the extent of CWA-regulated waters, but some were concerned that
expanding the CWA’s scope could impose costs on states and localities as their own actions (e.g.,
transportation projects) become subject to new requirements. Most environmental advocacy
groups welcomed the proposed guidance, which would more clearly define U.S. waters that are
subject to CWA protections, but some in these groups favored even a stronger document. Still,
both supporters and critics of the 2011 proposed guidance urged the agencies to replace guidance
with revised regulations that define “waters of the United States.” Three opinions in the 2006
Supreme Court Rapanos ruling similarly urged the agencies to initiate a rulemaking, as they now
have done.
In Congress, a number of legislative proposals were introduced to bar EPA and the Corps from
implementing the 2011 proposed guidance or developing regulations based on it; none of these
proposals was enacted. Similar criticism followed almost immediately after release of the
proposed rule on March 25, 2014, with some Members asserting that the proposed rule would
result in job losses and would damage economic growth. Supporters of the Administration, on the
other hand, defended the agencies’ efforts to protect U.S. waters and reduce frustration that has

1 Definition of “waters of the United States” is found at 33 C.F.R. § 328.3 (Corps) and 40 C.F.R. § 122.2 (EPA). The
term is similarly defined in other EPA regulations, as is the term “navigable waters.” See Table 1.
2 Solid Waste Agency of Northern Cook County v. U.S. Army Corps of Engineers (SWANCC), 531 U.S. 159 (2001),
and Rapanos v. United States, 547 U.S. 715 (2006).
3 For background on the Supreme Court rulings, subsequent guidance, and other developments, see CRS Report
RL33263, The Wetlands Coverage of the Clean Water Act (CWA): Rapanos and Beyond, by Robert Meltz and Claudia
Copeland.
Congressional Research Service
1

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”

resulted from the unclear jurisdiction of the act.4 Support was expressed by environmental and
conservation organizations, among others.5
The CWA and the Proposed Rule
The proposed rule was published in the Federal Register on April 21, 2014. The deadline for
public comments is July 21, 2014.6 Table 1 in this report provides a comparison of the current
regulatory language that defines “waters of the United States” with language in the proposed rule.
The CWA protects “navigable waters,” a term defined in the act to mean “the waters of the United
States, including the territorial seas.”7 Waters that are jurisdictional are subject to the multiple
regulatory requirements of the CWA: standards, discharge limitations, permits, and enforcement.
Non-jurisdictional waters, in contrast, do not have the federal legal protection of those
requirements. The act’s single definition of “navigable waters” applies to the entire law. In
particular, it applies to federal prohibition on discharges of pollutants except in compliance with
the act’s requirements (§301), requirements for point sources to obtain a permit prior to discharge
(§§402 and 404), water quality standards and measures to attain them (§303), oil spill liability
and oil spill prevention and control measures (§311), certification that federally permitted
activities comply with state water quality standards (§401), and enforcement (§309). It impacts
the Oil Pollution Act and other environmental laws, as well.8 The CWA leaves it to the agencies to
define the term “waters of the United States,” which EPA and the Corps have done several times,
most recently in 1986.
According to the agencies, the proposed rule would revise the existing administrative definition
of “waters of the United States” in regulations consistent with legal rulings—especially the recent
Supreme Court cases—and science concerning the interconnectedness of tributaries, wetlands,
and other waters to downstream waters and effects of these connections on the chemical,
physical, and biological integrity of downstream waters. It is particularly focused on clarifying
the regulatory status of waters located in isolated places in a landscape, the types of waters with
ambiguous jurisdictional status following the Supreme Court’s 2001 ruling in SWANCC, and
small streams, rivers that flow for part of the year, and nearby wetlands, the types of waters
affected by the Court’s 2006 ruling in Rapanos. In developing the proposed rule, EPA and the
Corps relied on a draft synthesis of more than 1,000 published and peer-reviewed scientific
reports; the synthesis discusses the current scientific understanding of the connections or isolation
of streams and wetlands relative to large water bodies such as river, lakes, estuaries, and oceans.
The purpose of the report is to summarize current understanding of these connections, the factors

4 Anthony Adragna and Amena Saiyid, “Republicans Contend EPA Overreached on Clean Water Act Jurisdiction
Proposal,” Daily Environment Report, vol. 58 (March 26, 2014), pp. A-7.
5 U.S. Environmental Protection Agency, “Here’s What They're Saying About the Clean Water Act Proposed Rule,”
press release, March 26, 2014, http://yosemite.epa.gov/opa/admpress.nsf/3881d73f4d4aaa0b85257359003f5348/
3f954c179cf0720985257ca7004920fa!OpenDocument.
6 Department of Defense, Department of the Army, Corps of Engineers, and Environmental Protection Agency,
“Definition of ‘Waters of the United States’ Under the Clean Water Act, Proposed Rule,” 79 Federal Register 22188-
22274, April 21, 2014.
7 CWA §502(7); 33 U.S.C. § 1362(7).
8 For example, the reach of the Endangered Species Act (ESA) is affected, because that act’s requirement for
consultation by federal agencies over impacts on threatened or endangered species is triggered through the issuance of
federal permits.
Congressional Research Service
2

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”

that influence them, and the mechanisms by which connected waters affect the function or
condition of downstream waters.9 This draft assessment document is under review by EPA’s
Science Advisory Board (SAB), which provides independent engineering and scientific advice to
the agency. A number of EPA’s critics have suggested that the agencies should have deferred
developing or proposing a revised rule until a final scientific review document is complete. In the
preamble to the proposed rule, the agencies state that the rule will not be finalized until the SAB’s
review and a final report are complete. However, some have expressed concern that the final
report will not be available during the public comment period on the rule.
Under the first section of the March 25 proposal, the following waters would be jurisdictional by
rule:
• Waters susceptible to interstate commerce, known as traditional navigable waters
(no change from current rules);
• All interstate waters, including interstate wetlands (no change from current
rules);
• The territorial seas (no change from current rules);
• Impoundments of the above waters or a tributary, as defined in the rule (no
change from current rules);
• Tributaries of the above waters (more inclusive than current rules because
“tributary” is newly and broadly defined); and
• All waters, including wetlands, that are adjacent to a water identified in the above
categories (by including all adjacent waters—not simply adjacent wetlands—the
proposal is more inclusive than current rules; these waters are considered
jurisdictional under the proposed rule because they have a significant nexus to a
traditional navigable water, interstate water, or the territorial seas).
The concept of significant nexus is critical because courts have ruled that, to establish CWA
jurisdiction between waters, there needs to be “some measure of the significance of the
connection for downstream water quality,” as Justice Kennedy found in the 2006 Rapanos case.
He said, “Mere hydrologic connection should not suffice in all cases; the connection may be too
insubstantial for the hydrologic linkage to establish the required nexus with navigable waters as
traditionally understood.”10 However, as EPA and the Corps observe in the March 25 proposed
rule, significant nexus is not itself a scientific term, but rather a determination of the agencies in
light of the law and science. Functions that might demonstrate significant nexus include sediment
trapping and retention of flood waters. In the proposed rule, the agencies note that a hydrologic
connection is not necessary to demonstrate significant nexus, because the function may be
demonstrated even in the absence of a connection (e.g., pollutant trapping is another such
function).

9 U.S. Environmental Protection Agency, Office of Research and Development, Connectivity of Streams and Wetlands
to Downstream Waters: A Review and Synthesis of the Scientific Evidence, External Review Draft, EPA/600/R-11-
098B, September 2013, http://yosemite.epa.gov/sab/sabproduct.nsf/0/7724357376745F48852579E60043E88C/$File/
WOUS_ERD2_Sep2013.pdf.
10 547 U.S. at 784-785.
Congressional Research Service
3

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”

“Other Waters”
Beyond the categories of waters that would be categorically jurisdictional under the proposed rule
is a category sometimes referred to as “other waters.” The regulatory term “other waters” applies
to wetlands and non-wetland waters that do not fall into the category of waters susceptible to
interstate commerce (traditional navigable waters), interstate waters, the territorial seas,
tributaries, or waters adjacent to waters in one of these four categories. Current rules contain a
non-exclusive list of “other waters,” such as intrastate lakes, mudflats, prairie potholes, and playa
lakes (see Table 1). Headwaters, which constitute most “other waters,” supply most of the water
to downstream traditional navigable waters, interstate waters, and the territorial seas.
EPA and the Corps recognize that the Supreme Court decisions in SWANCC and Rapanos put
limitations on the scope of “other waters” that may be determined to be jurisdictional under the
CWA. Much of the controversy since the Court’s rulings has focused on uncertainty as to what
degree “other waters” are jurisdictional, either by definition/rule, or as determined on a case-by-
case basis to evaluate significant nexus to a jurisdictional water. Under the 2008 guidance, which
remains in effect today, all “other waters” require a case-by-case evaluation to determine if a
significant nexus exists, thus providing a finding of CWA jurisdiction. There likewise has been
uncertainty as to what degree “other waters” that are similarly situated may be aggregated or
combined for a significant nexus determination.11 In the proposed rule, “other waters,” including
wetlands, that are adjacent to a jurisdictional water are categorically jurisdictional. Non-adjacent
“other waters” and wetlands will continue to require a case-by-case determination of significant
nexus. Also, the proposed rule allows broader aggregation of “other waters” that are similarly
situated than under the 2008 guidance, which could result in more “other waters” being found to
be jurisdictional following a significant nexus evaluation.
Some in the regulated community have urged EPA and the Corps to provide metrics, such as
quantifiable flow rates or minimum number of functions for “other waters,” to establish a
significant nexus to jurisdictional waters. The agencies declined to do so in the proposed rule,
saying that absolute standards would not allow sufficient flexibility to account for variability of
conditions and the varied functions that different waters provide.
The agencies acknowledge that there may be more than one way to determine which waters are
jurisdictional as “other waters,” and they are requesting comment on alternate approaches,
combination of approaches, scientific and technical data, case law, and other information that
would clarify which “other waters” should be considered categorically jurisdictional or following
a case-specific significant nexus determination.
In addition, EPA and the Corps are asking for public comment on whether to conclude by rule
that certain types of “other waters”—prairie potholes, western vernal pools, Carolina and
Delmarva bays, pocosins, Texas coastal prairie wetlands, and perhaps other categories of
waters—have a significant nexus and are per se jurisdictional. These waters would not require a
case-by-case analysis. At the same time, the agencies are asking for comment on whether to
determine by rule that playa lakes and perhaps other categories of waters do not have a significant

11 In the Rapanos ruling, Justice Kennedy stated that wetlands possess the requisite significant nexus if the wetlands,
“either alone or in combination with similarly situated [wet]lands in the region, significantly affect the chemical,
physical, and biological integrity of other covered waters more readily understood as ‘navigable.’” 547 U.S. at 780.
Congressional Research Service
4

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”

nexus and are not jurisdictional. If so determined, these waters would not be subject to a case-by-
case analysis of significant nexus.
Exclusions and Definitions
The second section of the proposed rule excludes specified waters from the definition of “waters
of the United States.” The listed waters and features would not be jurisdictional even if they
would otherwise be included within categories that are jurisdictional. The exclusions are:
• Waste treatment systems, including treatment ponds or lagoons, that are designed
to meet CWA requirements;
• Prior converted cropland;
• A list of features that have been excluded by long-standing practice and guidance
and would now be excluded by rule, such as artificially irrigated areas that would
revert to upland should application of irrigation water to the area cease (see
Table 1 for the full list); and
• Two types of ditches: ditches that are excavated wholly in uplands, drain only
uplands or non-jurisdictional waters, and have less than perennial (i.e.,
permanent) flow; and ditches that do not contribute flow, either directly or
through another water, to a traditional navigable water, interstate water,
impoundment, or the territorial seas. Other ditches, if they meet the rule’s
definition of “tributary,” would continue to be “waters of the United States”—a
point of much controversy with some stakeholders.
The proposed rule makes no change to and does not affect existing statutory and regulatory
exclusions, such as exemptions for normal farming, ranching, and silviculture activities (CWA
§404(f)); exemptions for permitting of agricultural stormwater discharges and return flows from
irrigated agriculture; or exemptions for water transfers that do not introduce pollutants into a
waterbody. Nor would it change permitting processes.
In the third section of the proposed rule, the agencies define terms, including “floodplain,”
“riparian area,” “tributary,” “significant nexus,” and “neighboring” as a component of the existing
term “adjacent.” The terms “adjacent” and “wetland” are not redefined. (See Table 1.)
Finally, the proposed rule includes two appendixes. One is an abbreviated, but lengthy, version of
the scientific assessment document currently being reviewed by EPA’s Science Advisory Board,
plus additional detail of the agencies’ reasoning concerning science in support of the proposed
rule; the other is an analysis of relevant case law.
Impacts of the Proposed Rule
The agencies acknowledge that the proposed rule would increase the asserted geographic scope of
CWA jurisdiction, when compared to a baseline of current practices under the existing regulations
and the 2003-2008 EPA-Corps guidance. This results in part from the agencies’ expressly
declaring some types of waters categorically jurisdictional (such as all waters adjacent to a
jurisdictional water), and also by application of definitions, which give larger regulatory context
to some types of waters, such as tributaries.
Congressional Research Service
5

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”

The agencies believe, however, that the proposed rule does not protect any new types of waters
that have not been protected historically (i.e., prior to the SWANCC and Rapanos rulings) or
exceed the CWA’s coverage. That is, while it would enlarge jurisdiction beyond that under the
2003 and 2008 EPA-Corps guidance, which the agencies believe was narrower than is justified by
science and the law, they believe that it would not enlarge jurisdiction beyond what is consistent
with the Supreme Court’s narrow reading of jurisdiction. Others may disagree. Many stakeholders
are concerned with what changes the proposed rule will make, how much additional waters will
be considered jurisdictional, and what additional costs will result.
The agencies’ broader assertion of jurisdiction, compared to existing regulation and current
practice, does not identify specific waters that will be found to be jurisdictional—that is, this or
that particular stream or pond—but the proposed rule attempts to draw more of a bright line of
CWA jurisdiction than in the past.
In an Economic Analysis document accompanying the proposed rule, EPA and the Corps estimate
that approximately 3% of U.S. waters would additionally be subject to CWA jurisdiction as a
result of the proposed rule, compared with current field practice, and thus subject to CWA
requirements. The estimated increase includes about 17% of “other waters” (discussed above)
that were not jurisdictional under the 2003/2008 guidance.12
According to the analysis, costs to regulated entities and governments (federal, state, and local)
are likely to increase. Direct and indirect costs would result from additional permit application
expenses (for CWA Section 404 permitting, stormwater permitting for construction and
development activities, and permitting of pesticide discharges and confined animal feeding
operations [CAFOs] for discharges to waters that would now be determined jurisdictional) and
additional requirements for oil storage and production facilities needing to develop and
implement spill prevention, control and countermeasure (SPCC) plans. Federal and state
governments would likely experience costs to administer and process additional permits. Other
costs would likely include compensatory mitigation requirements for permit impacts (if
applicable), affecting land developers and state and local governments. In all, the agencies
estimate that incremental costs associated with the rule range from $162 million to $279 million
per year.
The agencies believe that benefits accruing from the proposed rule include the value of ecosystem
services provided by the waters and wetlands protected as a result of CWA requirements, such as
habitat for aquatic and other species, support for recreational fishing and hunting, and flood
protection. Other benefits would include government savings on enforcement expenses, because
the rule is intended to provide greater regulatory certainty, thus reducing the need for government
enforcement. Business and government may also achieve savings from reduced uncertainty
concerning where CWA jurisdiction applies, they believe. In all, the agencies estimate that
benefits of the proposed rule range from $318 million to $514 million per year. However, they
note that “there is uncertainty and limitations associated with the results,” due to data and
information gaps, as well as analytic challenges. The analysis does not quantify all possible costs
and benefits.13 Overall, they conclude that benefits would exceed costs.

12 U.S. Environmental Protection Agency and U.S. Army Corps of Engineers, Economic Analysis of Proposed Revised
Definition of Waters of the United States, March 2014, http://www2.epa.gov/uswaters/economic-analysis-proposed-
revised-definition-waters-united-states, p. 12.
13 Ibid., pp. 21-22, 32.
Congressional Research Service
6

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”

Unclear for now is a question of the extent to which case law construing the existing
administrative definition of “waters of the United States” will continue to apply. Some of that
case law has been in place for more than 35 years. The preamble to the proposed rule does not
address this issue.
The agriculture sector has been vigorous in criticizing and challenging EPA regulatory actions
that may affect the sector’s operations, making potential impacts of the proposed rule on
agriculture a likely focus of controversy. One of the sector’s concerns about a new “waters of the
United States” rule has been whether it would modify existing statutory and regulatory
exemptions that exclude certain discharges from agricultural activities from CWA permitting. As
described above, the proposed rule makes no change and does not affect these exemptions, which
are self-implementing. An EPA fact sheet discusses the continued exclusions and exemptions.14
In addition, simultaneous with proposing the rule, EPA and the Corps issued an interpretive rule
that identifies 53 conservation practices approved by the U.S. Department of Agriculture’s
Natural Resources Conservation Service (NRCS) that additionally qualify for exemption under
the CWA Section 404(f)(1)(A) exclusion of “normal farming” activities from Section 404 permit
requirements and do not require determination whether the discharge involves a “water of the
United States.” Through this interpretive rule, the agencies intend to resolve uncertainties about
“normal farming” activities that are exempt from permitting when these conservation practices
are used. In other words, effective immediately, producers who utilize any of the 53 identified
practices according to NRCS technical standards need not seek a determination of CWA
jurisdiction and need not seek a CWA permit. The three agencies also have signed a
Memorandum of Understanding detailing implementation of the interpretive rule and identifying
a process for reviewing and updating the list of qualifying NRCS conservation practices.
Although the interpretive rule is already in effect, the agencies are accepting public comment
until June 5, 2014.15
Conclusion
The Corps and EPA will accept public comment on the proposed rule for 90 days, until July 21,
2014. If past experience regarding controversial proposals is a guide, however, it is likely that the
public comment period will be extended. Further, as noted above, the agencies pledge that a final
rule will not be promulgated before completion of EPA’s scientific assessment report; so, when
that may occur is likely to be some months in the future.
The EPA Administrator recently stated at a congressional hearing that it generally takes about one
year to finalize a rule. Complex and controversial rules can take much longer from proposal to
promulgation. Once a rule is finalized, legal challenges are likely, possibly delaying
implementation of any rule for years. New regulations may clarify many current questions, but

14 See http://www2.epa.gov/sites/production/files/2014-03/documents/cwa_ag_exclusions_exemptions.pdf.
15 Department of Defense, Department of the Army, Corps of Engineers, and Environmental Protection Agency,
“Notice of Availability Regarding the Exemption From Permitting Under Section 404(f)(1)(A) of the Clean Water Act
to Certain Agricultural Conservation Practices,” 79 Federal Register 22276, April 21, 2014.The list of practices, the
Memorandum of Understanding, and the interpretive rule are available at http://water.epa.gov/lawsregs/guidance/
wetlands/agriculture.cfm. USDA had no formal role in developing the Corps-EPA proposed rule, but it was among the
federal agencies commenting on it during interagency review.
Congressional Research Service
7

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”

they are unlikely to please all of the competing interests, as one environmental advocate
observed.
However, a rulemaking would only benefit wetlands if it did not reduce the jurisdiction
offered by current regulations and if the Administration remained faithful to sound science.
If politics were to trump science in the rulemaking process, the likelihood of such a
protective rule would not be promising. Also, rules are subject to legal challenge and can be
tied up in court for years before they are implemented.16




16 James Murphy, “Rapanos v. United States: Wading Through Murky Waters,” National Wetlands Newsletter, vol. 28,
no. 5, September-October 2006, p. 19.
Congressional Research Service
8

---

Table 1. Comparison of “Definition of Waters of the United States” Regulatory Language
Current Regulatory Language and Proposed Rule Announced by EPA and the Army Corps of Engineers March 25, 2014
Current Regulatory Languagea
Proposed Regulatory Language (3/25/2014)
Commentsb
(a) The term waters of the United States means
(a) For purposes of al sections of the Clean Water

Act, 33 U.S.C. 1251 et seq. and its implementing
regulations, subject to the exclusions in subsection (b)
of this section, the term “waters of the United States”
means:
(1) Al waters which are currently used, or were used
(1) All waters which are currently used, were used in
These waters are often referred to as “traditional
in the past, or may be susceptible to use in interstate or the past, or may be susceptible to use in interstate or
navigable waters” (TNWs), which include but are not
foreign commerce, including all waters which are
foreign commerce, including all waters which are
limited to the “navigable waters of the United States”
subject to the ebb and flow of the tide;
subject to the ebb and flow of the tide;
within the meaning of Section 10 of the Rivers and
Harbors Act of 1899. No change from the existing rule.
(2) All interstate waters including interstate wetlands;
(2) All interstate waters, including interstate wetlands;
These waters include tributaries to interstate waters,
waters adjacent to interstate waters, waters adjacent to
tributaries of interstate waters, and “other waters” that
have a significant nexus to interstate waters. No change
from the existing rule. Interstate waters would continue
to be “waters of the United States” even if they are not
navigable in fact and do not connect to such waters.
(3) All other waters such as intrastate lakes, rivers,
(7) On a case-specific basis, other waters, including
In the existing rule, there is a non-exclusive list of the
streams (including intermittent streams), mudflats,
wetlands, provided that those waters alone, or in
types of “other waters” which may be found to be
sandflats, wetlands, sloughs, prairie potholes, wet
combination with other similarly situated waters,
“waters of the U.S.” The existing description is omitted
meadows, playa lakes, or natural ponds, the use,
including wetlands, located in the same region, have a
under the proposal as unnecessary and confusing
degradation or destruction of which could affect
significant nexus to a water identified in paragraphs
because it includes some waters that would be
interstate or foreign commerce including any such
(a)(1) through (3) of this section.
jurisdictional under one of the categories of waters that
waters:
are jurisdictional by rule under the proposal (for
example, an intermittent stream that meets the
definition of tributary). Under the proposed rule,
“other waters” are not jurisdictional as a single
category but require a case-specific analysis of a
significant nexus to a traditional navigable water, an
interstate water, or the territorial seas. They may be
evaluated either individually, or as a group of waters
where they are determined to be similarly situated in a
region. “In the region” means the watershed that drains
CRS-9

---

Current Regulatory Languagea
Proposed Regulatory Language (3/25/2014)
Commentsb
to the nearest traditional navigable water, interstate
water, or the territorial seas through a single point of
entry. How other waters are aggregated for a case-
specific significant nexus analysis depends on the
functions they perform and their spatial arrangement
within the region or watershed. It is the landscape
position within the watershed that is the determinative
factor for the analysis, which will focus on the degree
to which the functions provided by the other waters
affect the chemical, physical, or biological integrity of
(a)(1) through (a)(3) waters.
Current rule asserts jurisdiction more broadly than
what is proposed; the proposal deletes language
requiring that an “other water” be one “the use,
degradation or destruction of which could affect
interstate commerce” and replaces it with requirement
that the “other water” meet the significant nexus
standard. The agencies consider this a substantial
change from the current rule.
(i) Which are or could be used by interstate or

Specific examples are omitted in the proposed rule as
foreign travelers for recreational or other purposes; or
unnecessary. The agencies say that the listing has led to
confusion where it has been incorrectly read as an
exclusive list.
(ii) From which fish or shellfish are or could be taken


and sold in interstate or foreign commerce; or
(iii) Which are used or could be used for industrial


purpose by industries in interstate commerce;
(4) All impoundments of waters otherwise defined as
(4) All impoundments of waters identified in paragraphs
Impoundments of a traditional navigable water,
waters of the United States under the definition;
(a)(1) through (3) and (5) of this section;
interstate water, the territorial seas, or a tributary are
jurisdictional by rule.
As a matter of policy and law, impoundments do not
de-federalize a water, even where there is no longer
flow below the impoundment. That is, damming or
impounding a water of the United States does not make
the water non-jurisdictional.
CRS-10

---

Current Regulatory Languagea
Proposed Regulatory Language (3/25/2014)
Commentsb
(5) Tributaries of waters identified in paragraphs (a)(1)
(5) All tributaries of waters identified in paragraphs
Tributaries, as defined in the proposed rule, of a
through (4) of this section;
(a)(1) through (4) of this section;
traditional navigable water, interstate water, the
territorial seas, or an impoundment would be
jurisdictional by rule.
Unless excluded under subsection (b) of the proposed
rule, any water that meets the proposed definition of
tributary is a water of the United States, whether it is
perennial, intermittent, or ephemeral. The water may
contribute flow directly or may contribute flow to
another water or waters that eventually flow into a
jurisdictional water. The tributary must drain, or be
part of a network of tributaries that drain, into an (a)(1)
through (a)(4) water.
“Tributary” is defined below.
(6) The territorial seas;
(3) The territorial seas;
Jurisdictional by rule; no change from the existing rule.
(7) Wetlands adjacent to waters (other than waters
(6) All waters, including wetlands, adjacent to a water
All waters, including wetlands, adjacent to a traditional
that are themselves wetlands) identified in paragraphs
identified in paragraphs (a)(1) through (5) of this
navigable water, interstate water, the territorial seas,
(a)(1) through (6) of this section.
section; and
impoundment, or tributary would be jurisdictional by
rule. Under the proposed rule, wetlands, ponds, lakes,
and similar waterbodies that are adjacent to traditional
navigable waters, interstate waters, and the territorial
seas, as well as waters and wetlands adjacent to other
jurisdictional waters such as tributaries and
impoundments, would be jurisdictional by rule.




(b) The fol owing are not “waters of the United States”
(8) Waters of the United States do not include prior
(2) Prior converted cropland. Notwithstanding the
No change proposed.
converted cropland.c Notwithstanding the
determination of an area’s status as prior converted
determination of an area’s status as prior converted
cropland by any other federal agency, for the purposes
cropland by any other Federal agency, for the purposes
of the Clean Water Act, the final authority regarding
of the Clean Water Act, the final authority regarding
Clean Water Act jurisdiction remains with EPA.
Clean Water Act jurisdiction remains with EPA.
CRS-11

---

Current Regulatory Languagea
Proposed Regulatory Language (3/25/2014)
Commentsb
Waste treatment systems, including treatment ponds or (1) Waste treatment systems, including treatment
The agencies do not believe that omitting the
lagoons designed to meet the requirements of CWA
ponds or lagoons, designed to meet the requirements
parenthetical reference to 40 CFR 423.11(m) is a
(other than cooling ponds as defined in 40 CFR
of the Clean Water Act.
change in substance to the waste treatment exclusion
423.11(m) which also meet the criteria of this
or how it is applied.
definition) are not waters of the United States.d

(3) Ditches that are excavated wholly in uplands, drain
Proposed rule would codify long-standing practice and
only uplands or non-jurisdictional waters, and have less
guidance (including 1986 and 1988 preamble language),
than perennial flow.
which has been to exclude these waters from
jurisdiction.
Excluded ditches must be dug only in uplands, drain
only uplands, and have ephemeral or intermittent flow.
Water that only stands or pools in a ditch is not
considered perennial flow and, therefore, any such
upland ditch would not be subject to regulation.
Other ditches, if they meet the new proposed definition
of “tributary,” would continue to be waters of the U.S.
Ditches may function as point sources that discharge
pol utants, thus subject to CWA Section 402.

(4) Ditches that do not contribute flow, either directly
Proposed rule would codify long-standing practice and
or through another water, to a water identified in
guidance (including 1986 and 1988 preamble language),
paragraphs (a)(1) through (4) of this section.
which has been to exclude these waters from
jurisdiction. These waters would not be jurisdictional by
rule.
Ditches that do not contribute flow to the tributary
system of a traditional navigable water, interstate water,
impoundment, or the territorial seas are not “waters of
the United States,” even if the ditch has a perennial
flow.
Other ditches, if they meet the new proposed definition
of “tributary,” would continue to be waters of the U.S.
Ditches may function as point sources that discharge
pol utants, thus subject to CWA Section 402.

CRS-12

---

Current Regulatory Languagea
Proposed Regulatory Language (3/25/2014)
Commentsb

(5) The following features: (i) Artificially irrigated areas
Proposed rule would codify long-standing practice and
that would revert to upland should application of
guidance (including 1986 and 1988 preamble language),
irrigation water to that area cease; (ii) artificial lakes or
which has been to exclude these waters from
ponds created by excavating and/or diking dry land and
jurisdiction. These waters would not be jurisdictional by
used exclusively for such purposes as stock watering,
rule.
irrigation, settling basins, or rice growing; (ii ) artificial
reflecting pools or swimming pools created by
excavating and/or diking dry land; (iv) small ornamental
waters created by excavating and/or diking dry land for
primarily aesthetic reasons; (v) water-filled depressions
created incidental to construction activity; (vi)
groundwater drained through subsurface drainage
systems; and (vii) gullies and rills and non-wetland
swales.



(c) Definitions—
(b) The term wetlands means those areas that are
(6) Wetlands: The term wetlands means those areas
No change proposed.
inundated or saturated by surface or ground water at a
that are inundated or saturated by surface or ground
frequency and duration sufficient to support, and that
water at a frequency and duration sufficient to support,
Wetlands are ecosystems that often occur at the edge
under normal circumstances do support, a prevalence
and that under normal circumstances do support, a
of aquatic (water, fresh or salty) or terrestrial (upland)
of vegetation typically adapted for life in saturated soil
prevalence of vegetation typically adapted for life in
systems. Wetlands typically represent transitional zones
conditions. Wetlands generally include swamps,
saturated soil conditions. Wetlands generally include
between aquatic and upland systems.
marshes, bogs, and similar areas.
swamps, marshes, bogs, and similar areas.
(c) The term adjacent means bordering, contiguous, or
(1) Adjacent: The term adjacent means bordering,
Current rule limits consideration of adjacency to
neighboring. Wetlands separated from other waters of
contiguous or neighboring. Waters, including wetlands,
wetlands. Proposed rule would change “adjacent
the United States by man-made dikes or barriers,
separated from other waters of the United States by
wetlands” to “adjacent waters” so that waterbodies
natural river berms, beach dunes and the like are
man-made dikes or barriers, natural river berms, beach
such as ponds and oxbow lakes [a U-shaped body of
‘‘adjacent wetlands.’’
dunes and the like are “adjacent waters.”
water formed when a wide meander from a river is cut
off to form a lake] as well as wetlands that are adjacent
to jurisdictional waters are “waters of the U.S.” by
regulation. The rule would include wetlands and other
waterbodies that meet the proposed definition of
adjacent, including “neighboring,” which is defined
separately. Adjacent waters are those that provide
similar functions which, together with functions provided
by tributaries to which they are adjacent, have a significant
CRS-13

---

Current Regulatory Languagea
Proposed Regulatory Language (3/25/2014)
Commentsb
nexus to traditional navigable waters (TNWs),
interstate waters, and the territorial seas. “In the
aggregate, all adjacent waters have a significant nexus
with their downstream TNWs or interstate waters.”
The lateral limits of an adjacent water, other than
wetlands or tributaries, are determined by the presence
of an ordinary high water mark (OHWM) without the
need for a bed and banks. Deletion of parenthetical
phrase in the existing rule is intended to ensure that all
waters that meet the proposed definitions of “adjacent”
are “waters of the U.S.” regardless of whether or not
another adjacent water is located between those
waters and the tributary.
(d) The term high tide line means the line of intersection No change proposed

of the land with the water’s surface at the maximum
height reached by a rising tide. The high tide line may
be determined, in the absence of actual data, by a line
of oil or scum along shore objects, a more or less
continuous deposit of fine shel or debris on the
foreshore or berm, other physical markings or
characteristics, vegetation lines, tidal gages, or other
suitable means that delineate the general height reached
by a rising tide. The line encompasses spring high tides
and other high tides that occur with periodic frequency
but does not include storm surges in which there is a
departure from the normal or predicted reach of the
tide due to the piling up of water against a coast by
strong winds such as those accompanying a hurricane
or other intense storm.
(e) The term ordinary high water mark means that line on No change proposed

the shore established by the fluctuations of water and
indicated by physical characteristics such as clear,
natural line impressed on the bank, shelving, changes in
the character of soil, destruction of terrestrial
vegetation, the presence of litter and debris, or other
appropriate means that consider the characteristics of
the surrounding area.
CRS-14

---

Current Regulatory Languagea
Proposed Regulatory Language (3/25/2014)
Commentsb
(f) The term tidal waters means those waters that rise
No change proposed

and fall in a predictable and measurable rhythm or cycle
due to the gravitational pulls of the moon and sun. Tidal
waters end where the rise and fall of the water surface
can no longer be practical y measured in a predictable
rhythm due to masking by hydrologic, wind, or other
effects.
(2)
Neighboring: The term neighboring, for purposes
Waters, including wetlands, that are located within the
of the term “adjacent” in this section, includes waters
riparian area or floodplain of an (a)(1) through (a)(5)
located within the riparian area or floodplain of a water
water would be jurisdictional without a case-specific
identified in paragraphs (a)(1) through (a)(5) of this
significant nexus analysis. Even if separated from such a
section, or waters with a surface or shallow subsurface
water by natural or man-made features (e.g., a berm),
hydrologic connection to such a jurisdictional water.
the water would be adjacent and thus jurisdictional.
(3)
Riparian area: The term riparian area means an
The term “riparian area” is used to help identify waters,
area bordering a water where surface or subsurface
including wetlands, that may be “adjacent” and would,
hydrology influence the ecological processes and plant
therefore, be “waters of the United States” under the
and animal community structure in that area. Riparian
proposed rule. No uplands located in “riparian areas”
areas are transitional areas between aquatic and
can ever be “waters of the United States.”
terrestrial ecosystems that influence the exchange of
energy and materials between those ecosystems.
(4)
Floodplain: The term floodplain means an area
The term “floodplain” is used to help identify waters,
bordering inland or coastal waters that was formed by
including wetlands, that may be “adjacent” and would,
sediment deposition from such water under present
therefore, be “waters of the United States” under the
climatic conditions and is inundated during periods of
proposed rule. No uplands located in “floodplains” can
moderate to high water flows.
ever be “waters of the United States.”
(5)
Tributary: The term tributary means a waterbody
This term has not previously been defined in any
physically characterized by the presence of a bed and
regulation or preamble.
banks and ordinary high water mark, as defined at 33
CFR § 328.3(e), which contributes flow, either directly
Bed and banks and ordinary high water mark (OHWM)
or through another water, to a water identified in
are features that generally are physical indicators of
paragraphs (a)(1) through (4) of this section. In addition, flow. OHWM generally defines the lateral limits of a
wetlands, lakes, and ponds are tributaries (even if they
water. In many tributaries, the bed is that part of the
lack a bed and banks or ordinary high water mark) if
channel below the OHWM, and the banks often extend
they contribute flow, either directly or through another above the OHWM.
water to a water identified in paragraphs (a)(1) through
Wetland tributaries are wetlands that are located
(3) of this section. A water that otherwise qualifies as a
within the stream channel itself or that form the start
CRS-15

---

Current Regulatory Languagea
Proposed Regulatory Language (3/25/2014)
Commentsb
tributary under this definition does not lose its status as of the stream channel.
a tributary if, for any length, there are one or more
man-made breaks (such as bridges, culverts, pipes, or
Man-altered and man-made tributaries perform many of
dams) or one or more natural breaks (such as wetlands
the same functions as natural tributaries and provide
at the head of or along the run of a stream, debris piles, connectivity between streams and downstream rivers.
boulder fields, or a stream that flows underground) so
long as a bed and banks and an ordinary high water
mark can be identified upstream of the break. A
tributary, including wetlands, can be a natural, man-
altered, or man-made waterbody and includes waters
such as rivers, streams, lakes, ponds, impoundments,
canals, and ditches not excluded in paragraph (b)(3) or
(4) of this section.
(7)
Significant nexus: The term significant nexus
A significant nexus analysis may be based on a particular
means that a water, including wetlands, either alone or
water alone or on the effect that the water has in
in combination with other similarly situated waters in
combination with other similarly situated waters in the
the region (i.e., the watershed that drains to a water
region. “Region” means the watershed that drains to a
identified in paragraphs (a)(1) through (3) of this
water identified in (a)(1) through (a)(3) through a single
section), significantly affects the chemical, physical or
point of entry.
biological integrity of a water identified in paragraphs
(a)(1) through (3) of this section. For an effect to be
Proposed rule adopts the concept of aggregating certain
significant, it must be more than speculative or
waters to determine whether they meet the “alone or
insubstantial. Other waters, including wetlands, are
in combination with similarly situated waters” test of
similarly situated when they perform similar functions
Justice Kennedy. Waters must perform similar functions
and are located sufficiently close together or close to a
and be located sufficiently close together or close to a
“water of the U.S.” so that they can be evaluated as a
traditional navigable water, interstate water, or the
single landscape unit with regard to their effect on the
territorial seas so that they can be evaluated as a single
chemical, physical, or biological integrity of a water
landscape unit with regard to their effects. Examining
identified in paragraphs (a)(1) through (3) of this
both functionality and proximity limits the “other
section.
waters” that can be aggregated for purposes of
determining jurisdiction.
Functions that might demonstrate significant nexus
include sediment trapping and retention of flood
waters. A hydrologic connection is not necessary,
because the function may be demonstrated even in the
absence of a connection (e.g., pol utant trapping).
Source: Prepared by CRS.
CRS-16

---

Notes:
a. 33 C.F.R. 328.3, 40 C.F.R. 122.2, 40 C.F.R. 230.3, and 40 C.F.R. 232.2 (definition of “waters of the United States”). The term “navigable waters” is defined at 40
C.F.R. 110.1 (Discharge of Oil); 40 C.F.R. 112.2 (Oil Pollution Prevention); 40 C.F.R. 116.3 (Designation of Hazardous Substance); 40 C.F.R. 117.1(i) (Determination
of Reportable Quantities for Hazardous Substances); 40 C.F.R. 300.5 and Appendix E 1.5 to Part 300 (National Oil and Hazardous Substances Pollution Contingency
Plan); and 40 C.F.R. 302.3 (Designation, Reportable Quantities, and Notification).
b. Comments in this table are drawn in large part from the preamble to the proposed rule.
c. The term “prior converted cropland” is included in the U.S. Department of Agriculture’s administrative definition of the term “wetland” (see 7 C.F.R. 12.2).
d. A definition of “waste treatment system is found in EPA regulations (35 C.F.R. 35.905): “Complete waste treatment system. A complete waste treatment system
consists of all of the treatment works necessary to meet the requirements of title III of the Act, involved in (a) The transport of waste waters from individual homes
or buildings to a plant or facility where treatment of the waste water is accomplished; (b) the treatment of the waste waters to remove pollutants; and (c) the
ultimate disposal, including recycling or reuse, of the treated waste waters and residues which result from the treatment process. One complete waste treatment
system would, normally, include one treatment plant or facility, but also includes two or more connected or integrated treatment plants or facilities.”

CRS-17

---

EPA and the Army Corps’ Proposed Rule to Define “Waters of the United States”


Author Contact Information
Claudia Copeland
Specialist in Resources and Environmental Policy
ccopeland@crs.loc.gov, 7-7227

Congressional Research Service
18

---