Waters of the United States (WOTUS): Frequently Asked Questions About the Scope of the Clean Water Act

Changes from February 23, 2023 to June 22, 2023

This page shows textual changes in the document between the two versions indicated in the dates above. Textual matter removed in the later version is indicated with ~~red strikethrough~~ and textual matter added in the later version is indicated with blue.

Waters of the United States (WOTUS):
~~February 23~~June 22, 2023 , 2023
Frequently Asked Questions About the Scope
Kate R. Bowers
of the Clean Water Act
Legislative Attorney Legislative Attorney

Congress established the Federal Water Pollution Control Act, also known as the Clean Water Congress established the Federal Water Pollution Control Act, also known as the Clean Water
Laura Gatz
Act (CWA), to restore and protect the quality of the nation’s surface waters. The CWA protects Act (CWA), to restore and protect the quality of the nation’s surface waters. The CWA protects
Specialist in Environmental Specialist in Environmental
“navigable waters,” defined in the statute as “waters of the United States, including the territorial “navigable waters,” defined in the statute as “waters of the United States, including the territorial
Policy Policy
seas.” The CWA does not further define the term seas.” The CWA does not further define the term waters of the United States (WOTUS), which (WOTUS), which

determines which waters are federally regulated. Thus, in implementing the CWA, the Army determines which waters are federally regulated. Thus, in implementing the CWA, the Army
Corps of Engineers (Corps) and the Environmental Protection Agency (EPA)—the two agencies Corps of Engineers (Corps) and the Environmental Protection Agency (EPA)—the two agencies

that administer the statute—have defined the term in regulations. However, Congress’s intent as that administer the statute—have defined the term in regulations. However, Congress’s intent as
to the meaning of WOTUS has been debated and litigated for more than four decades. to the meaning of WOTUS has been debated and litigated for more than four decades.
The Supreme Court and lower courts have also weighed in on the scope of the term. For much of the past several decades, regulations promulgated by the Corps and EPA in the 1980s have been in effect. For much of the past several decades, regulations promulgated by the Corps and EPA in the 1980s have been in effect.
(These regulations, as further interpreted by the courts and agencies are often referred to as the (These regulations, as further interpreted by the courts and agencies are often referred to as the pre-2015 rules.) The agencies .) The agencies
supplemented these regulations with guidance, which they developed in response to supplemented these regulations with guidance, which they developed in response to prior Supreme Court rulings related to the Supreme Court rulings related to the
scope of the federal government’s ability to regulate WOTUS. The Corps and EPA acknowledged that their guidance did not scope of the federal government’s ability to regulate WOTUS. The Corps and EPA acknowledged that their guidance did not
provide the public or agency staff with the information needed to ensure timely, predictable, and consistent jurisdictional provide the public or agency staff with the information needed to ensure timely, predictable, and consistent jurisdictional
determinations. Diverse stakeholders and Members of Congress requested a formal rulemaking to revise existing regulations. determinations. Diverse stakeholders and Members of Congress requested a formal rulemaking to revise existing regulations.
Successive presidential administrations have engaged in efforts to define WOTUS in regulation. Both the Obama Successive presidential administrations have engaged in efforts to define WOTUS in regulation. Both the Obama
Administration’s 2015 Clean Water Rule and the Trump Administration’s 2020 Navigable Waters Protection Rule prompted Administration’s 2015 Clean Water Rule and the Trump Administration’s 2020 Navigable Waters Protection Rule prompted
strong reactions from a variety of stakeholders, with numerous groups filing lawsuits challenging the rules. On January 18, strong reactions from a variety of stakeholders, with numerous groups filing lawsuits challenging the rules. On January 18,
2023, the Corps and EPA, under the Biden Administration, issued a new rule (the 2023 WOTUS Rule) redefining WOTUS in 2023, the Corps and EPA, under the Biden Administration, issued a new rule (the 2023 WOTUS Rule) redefining WOTUS in
the agencies’ regulations. The Corps and EPA the agencies’ regulations. The Corps and EPA ~~have~~ asserted that their intent in promulgating the 2023 WOTUS Rule was to asserted that their intent in promulgating the 2023 WOTUS Rule was to
redefine WOTUS in a durable regulation, updating the pre-2015 rules to reflect consideration of redefine WOTUS in a durable regulation, updating the pre-2015 rules to reflect consideration of past Supreme Court decisions, Supreme Court decisions,
science, and the agencies’ experience and technical expertise. In general, the rule defines WOTUS more narrowly than the science, and the agencies’ experience and technical expertise. In general, the rule defines WOTUS more narrowly than the
Clean Water Rule and more broadly than the Navigable Waters Protection Rule.Clean Water Rule and more broadly than the Navigable Waters Protection Rule.
~~While some stakeholders have expressed support for the 2023 WOTUS Rule, others believe that~~ The 2023 WOTUS Rule went into effect on March 20, 2023, and was immediately challenged. Three courts have stayed implementation of the 2023 WOTUS Rule in a total of 27 states and as applied to several associations that are participating in the litigation. For those states and plaintiffs, the Corps and EPA are interpreting WOTUS consistent with the pre-2015 framework. While some stakeholders support the 2023 WOTUS Rule, others believe it defines WOTUS too it defines WOTUS too
broadly, does not provide regulatory clarity, and should not have been issued prior to the resolution of a broadly, does not provide regulatory clarity, and should not have been issued prior to the resolution of a ~~pending Supreme~~
~~Court case addressing aspects of the scope of WOTUS. The new rule is the subject of stakeholder commentary, congressional~~
~~action, and litigation.~~
~~Some stakeholders have urged Congress to take actions regarding regulation of WOTUS.~~ Supreme Court case that was pending at the time the rule was promulgated. In June 2023, that Supreme Court case—Sackett v. EPA—was decided. The majority in Sackett formally adopted the approach taken by a four-Justice plurality in the 2006 case Rapanos v. United States and rejected elements of the jurisdictional test that are present in the 2023 WOTUS Rule. While many questions about the implications of the Court’s decision remain, the ruling significantly narrows the scope of WOTUS in comparison not only to the 2023 WOTUS Rule but also to any of the regulations the agencies have promulgated to define WOTUS. In the 118th Congress, Members In the 118th Congress, Members
have introduced have introduced legislation pertaining to WOTUS, including a joint resolution to revoke the 2023 WOTUS Rule through the Congressional Review Acta joint resolution to revoke the 2023 WOTUS Rule through the Congressional Review Act, which passed both chambers but was vetoed by the President. ~~. Members may~~
~~take action to specifically~~Members have also introduced legislation to define the term through amendments to the CWA define the term through amendments to the CWA~~, introducing legislation, for example, to narrow~~
~~the term’s scope, as was done in the 117th Congress. Committees in the 117th Congress and the 116th Congress held multiple~~
~~oversight hearings to assess the impacts of rules at that time, and the 118th Congress may conduct similar oversight.~~

. Looking forward, Congress may seek to oversee the Biden Administration’s efforts to implement the Supreme Court’s decision in Sackett v. EPA or may consider introducing legislation to define the scope of WOTUS if it seeks to clarify its intent as to the scope of the term. Congressional Research Service Congressional Research Service

Waters of the United States (WOTUS): Frequently Asked Questions

ongress established the Federal Water Pollution Control Act, also known as the Clean ongress established the Federal Water Pollution Control Act, also known as the Clean
Water Act (CWA), to restore and protect the quality of the nation’s surface waters.1 The Water Act (CWA), to restore and protect the quality of the nation’s surface waters.1 The
C Clean Water Act protects “navigable waters,” defined in the statute as “waters of the C Clean Water Act protects “navigable waters,” defined in the statute as “waters of the
United States, including the territorial seas.”2 The CWA does not define United States, including the territorial seas.”2 The CWA does not define “waters of the United waters of the United
StatesStates” (WOTUS). The scope of the term determines which waters are federally regulated, and (WOTUS). The scope of the term determines which waters are federally regulated, and
thus which waters are subject to CWA requirements and programs. These include CWA thus which waters are subject to CWA requirements and programs. These include CWA
permitting requirements; water quality certifications; water quality standards, impaired waters, permitting requirements; water quality certifications; water quality standards, impaired waters,
and total maximum daily loads; and other CWA and non-CWA programs. and total maximum daily loads; and other CWA and non-CWA programs.
Successive Successive ~~administrations~~Administrations have struggled to interpret the term have struggled to interpret the term waters of the United States for the for the
purpose of implementing various requirements of the CWA. Prior to the Biden Administration, purpose of implementing various requirements of the CWA. Prior to the Biden Administration,
executive branch efforts to define WOTUS administratively included regulations promulgated by executive branch efforts to define WOTUS administratively included regulations promulgated by
the Army Corps of Engineers (Corps) and the Environmental Protection Agency (EPA) in the the Army Corps of Engineers (Corps) and the Environmental Protection Agency (EPA) in the
1980s and supplemented with interpretive guidance developed in response to Supreme Court 1980s and supplemented with interpretive guidance developed in response to Supreme Court
rulings; the 2015 Clean Water Rule; and the 2020 Navigable Waters Protection Rule.3 The rulings; the 2015 Clean Water Rule; and the 2020 Navigable Waters Protection Rule.3 The
agencies’ efforts to define WOTUS in regulation during both the Obama and Trump agencies’ efforts to define WOTUS in regulation during both the Obama and Trump
Administrations were controversial and led to litigation. Many observers viewed the Obama Administrations were controversial and led to litigation. Many observers viewed the Obama
Administration’s 2015 Clean Water Rule as defining WOTUS too broadly, while many viewed Administration’s 2015 Clean Water Rule as defining WOTUS too broadly, while many viewed
the Trump Administration’s 2020 Navigable Waters Protection Rule as defining WOTUS too the Trump Administration’s 2020 Navigable Waters Protection Rule as defining WOTUS too
narrowly. A federal district court vacated the narrowly. A federal district court vacated the 2020 Navigable Waters Protection Rule in September Navigable Waters Protection Rule in September
2021, after which the Corps and EPA announced that they had halted implementation of the rule.4 2021, after which the Corps and EPA announced that they had halted implementation of the rule.4
On January 18, 2023, the Corps and EPA published a new rule (the 2023 WOTUS Rule) revising On January 18, 2023, the Corps and EPA published a new rule (the 2023 WOTUS Rule) revising
the definition of WOTUS.5 The agencies the definition of WOTUS.5 The agencies ~~have~~ asserted that their intent in promulgating the 2023 asserted that their intent in promulgating the 2023
WOTUS Rule was to redefine WOTUS in a durable regulation, updating the pre-2015 rules to WOTUS Rule was to redefine WOTUS in a durable regulation, updating the pre-2015 rules to
reflect consideration of Supreme Court decisions, science, and the agencies’ experience and reflect consideration of Supreme Court decisions, science, and the agencies’ experience and
technical expertise.6 technical expertise.6
Some stakeholders Some stakeholders ~~have expressed support for~~supported the 2023 WOTUS Rule, in some cases observing the 2023 WOTUS Rule, in some cases observing
that the rule takes a middle road between the that the rule takes a middle road between the 2015 Clean Water Rule and the Clean Water Rule and the 2020 Navigable Waters Navigable Waters
Protection Rule.7 Others Protection Rule.7 Others ~~have~~ expressed opposition to the 2023 WOTUS Rule, arguing that it expressed opposition to the 2023 WOTUS Rule, arguing that it
does not provide regulatory clarity, is overly broad, and that the Corps and EPA should have does not provide regulatory clarity, is overly broad, and that the Corps and EPA should have
delayed issuing a rule pending the resolution of delayed issuing a rule pending the resolution of Sackett v. EPA, a Supreme Court case addressing aspects of the a Supreme Court case addressing aspects of the
~~scope of WOTUS. The new rule is scheduled to take effect on March 20, 2023, though it is~~

scope of WOTUS. 1 33 U.S.C. §1 33 U.S.C. § 1251 1251 et seq.
2 33 U.S.C. §2 33 U.S.C. § 1362(7). 1362(7).
3 Army Corps of Engineers and EPA, “Clean Water Rule: Definition of ‘Waters of the United States’; Final Rule,” 803 Army Corps of Engineers and EPA, “Clean Water Rule: Definition of ‘Waters of the United States’; Final Rule,” 80
Federal Register 37054, June 29, 2015 (hereinafter “2015 Clean Water Rule”); Army Corps of Engineers and EPA, 37054, June 29, 2015 (hereinafter “2015 Clean Water Rule”); Army Corps of Engineers and EPA,
“The Navigable Waters Protection Rule: Definition of ‘Waters of the United States,’” 85“The Navigable Waters Protection Rule: Definition of ‘Waters of the United States,’” 85 Federal Register 22250, 22250, ~~April~~Apr.
21, 2020 (hereinafter “Navigable Waters Protection Rule”). 21, 2020 (hereinafter “Navigable Waters Protection Rule”).
4 Pascua Yaqui Tribe v. EPA, 557 F. Supp. 3d 949 (D. Ariz. 2021). 4 Pascua Yaqui Tribe v. EPA, 557 F. Supp. 3d 949 (D. Ariz. 2021).
5 Revised Definition of “Waters of the United States,” 88 5 Revised Definition of “Waters of the United States,” 88 Federal Register 3004, 3004, ~~January~~Jan. 18, 2023 (hereinafter “2023 18, 2023 (hereinafter “2023
WOTUS Rule”). The final rule was published on WOTUS Rule”). The final rule was published on ~~January~~Jan. 18, 2023. The agencies released a pre-publication version of 18, 2023. The agencies released a pre-publication version of
the rule on the rule on ~~December~~Dec. 30, 2022. 30, 2022.
6 2023 WOTUS Rule, p. 3019. See also Corps and EPA, 6 2023 WOTUS Rule, p. 3019. See also Corps and EPA, Final Rule: Revised Definition of ‘Waters of the United States’
Fact Sheet, , ~~December~~Dec. 2022, https://www.epa.gov/system/files/documents/2022-12/Public%20Fact%20Sheet.pdf 2022, https://www.epa.gov/system/files/documents/2022-12/Public%20Fact%20Sheet.pdf
(hereinafter “2022 WOTUS Fact Sheet”). (hereinafter “2022 WOTUS Fact Sheet”).
7 See, for example, David LaRoss, “Touting ‘Durable’ Approach, EPA Adopts Dual Tests in Revised WOTUS Rule,” 7 See, for example, David LaRoss, “Touting ‘Durable’ Approach, EPA Adopts Dual Tests in Revised WOTUS Rule,”
InsideEPA.com, , ~~December~~Dec. 30, 2022. 30, 2022.
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~~already the subject of litigation. Additionally, Members have introduced a joint resolution~~
~~disapproving the rule under the Congressional Review Act.~~
~~This report addresses frequently asked questions about WOTUS and the 2023 WOTUS Rule,~~
The 2023 WOTUS Rule went into effect on March 20, 2023, and was immediately challenged.8 While no court has issued a ruling on the merits of the rule, some courts have issued orders temporarily barring implementation of the rule while litigation is pending. In the 27 states and as to the associations and their members that are covered by those orders, the Corps and EPA are interpreting WOTUS consistent with the pre-2015 regulatory framework. Apart from the pending litigation challenging the 2023 WOTUS Rule, in May 2023, the Supreme Court issued its ruling in Sackett v. EPA. In Sackett, the Court construed the reach of the CWA more narrowly than the new or previous regulatory interpretations or the approach adopted by the courts of appeals following an earlier Supreme Court decision regarding WOTUS. While the Corps and EPA have not indicated what steps they will take to implement the Court’s decision, the limitations imposed by the Court’s ruling cast doubt on the continued validity of the 2023 WOTUS Rule. Many questions about the implications of the Court’s decision remain, but the ruling significantly narrows the scope of WOTUS in comparison to any of the regulations the agencies have promulgated to define WOTUS. This report addresses frequently asked questions about WOTUS, including actions taken by prior administrations, the including actions taken by prior administrations, the ~~contents of the new rule, stakeholder~~
~~responses and litigation~~2023 WOTUS Rule, the Supreme Court’s ruling in Sackett v. EPA, potential implications of the ruling, and options for Congress. , and options for Congress.
What Actions Have Previous Administrations Taken
to Define WOTUS?
Pre-2015 Rules and Guidance
For much of the past several decades, regulations promulgated by the Corps and EPA in 1986 and For much of the past several decades, regulations promulgated by the Corps and EPA in 1986 and
1988, respectively, have been in effect.1988, respectively, have been in effect.89 The agencies have supplemented these regulations with The agencies have supplemented these regulations with
interpretive guidance developed in response to Supreme Court rulings related to the scope of the interpretive guidance developed in response to Supreme Court rulings related to the scope of the
federal government’s ability to regulate WOTUS.federal government’s ability to regulate WOTUS.910
One such Supreme Court case remains particularly relevant to the most recent efforts to redefine One such Supreme Court case remains particularly relevant to the most recent efforts to redefine
WOTUS. In WOTUS. In Rapanos v. United States, the Court considered the extent of CWA jurisdiction over , the Court considered the extent of CWA jurisdiction over
wetlands near ditches or man-made drains that emptied into traditional navigable waters.wetlands near ditches or man-made drains that emptied into traditional navigable waters.1011 The The
Court’s decision in Court’s decision in Rapanos yielded three different opinions, none of which garnered a yielded three different opinions, none of which garnered a
controlling majority for a single standard to govern future jurisdictional disputes. Instead, the controlling majority for a single standard to govern future jurisdictional disputes. Instead, the
decision resulted in two alternative tests for evaluating jurisdictional waters: a “relatively decision resulted in two alternative tests for evaluating jurisdictional waters: a “relatively
permanent” test set forth by a four-Justice plurality in an opinion authored by Justice Antonin permanent” test set forth by a four-Justice plurality in an opinion authored by Justice Antonin
~~Scalia, and a “significant nexus” test proposed by Justice Anthony Kennedy in a concurring~~
~~opinion.~~

8 8 Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex.); West Virginia v. EPA, No. 3:23-cv-00032 (D.N.D.); Kentucky v. EPA, No. 3:23-cv-00007 (E.D. Ky.). 9 Army Corps of Engineers, “Final Rule for Regulatory Programs of the Corps of Engineers,” 51 Army Corps of Engineers, “Final Rule for Regulatory Programs of the Corps of Engineers,” 51 Federal Register
41206, 41206, ~~November~~Nov. 13, 1986 (hereinafter “1986 Corps Rule”); EPA, “Clean Water Act Section 404 Program Definitions 13, 1986 (hereinafter “1986 Corps Rule”); EPA, “Clean Water Act Section 404 Program Definitions
and Permit Exemptions; Section 404 State Program Regulations,” 53 and Permit Exemptions; Section 404 State Program Regulations,” 53 Federal Register 20764, June 6, 1988 ( 20764, June 6, 1988 (hereinafter “1988 EPA 1988 EPA
RuleRule"). ).
910 Army Corps of Engineers and EPA, “Appendix A, Joint Memorandum,” 68 Army Corps of Engineers and EPA, “Appendix A, Joint Memorandum,” 68 Federal Register 1995, 1995, ~~January~~Jan. 15, 2003; 15, 2003;
Benjamin H. Grumbles, Assistant Administrator for Water, EPA, and John Paul Woodley Jr., Assistant Secretary of the Benjamin H. Grumbles, Assistant Administrator for Water, EPA, and John Paul Woodley Jr., Assistant Secretary of the
Army (Civil Works), Department of the Army, Army (Civil Works), Department of the Army, Clean Water Act Jurisdiction Following the U.S. Supreme Court’s
Decision in Rapanos v. United States & Carabell v. United States, memorandum, , memorandum, ~~December~~Dec. 2, 2008 (hereinafter “2008 2, 2008 (hereinafter “2008
Rapanos Guidance”). Guidance”).
10 11 547 U.S. 715 (2006). 547 U.S. 715 (2006).
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Scalia, and a “significant nexus” test proposed by Justice Anthony Kennedy in a concurring opinion. Rapanos and the Relatively Permanent and Significant Nexus Tests
The Plurality’s “Relatively Permanent” Test: Writing for a four-Justice plurality, Justice Scalia wrote that Writing for a four-Justice plurality, Justice Scalia wrote that
the word “waters” in “waters of the United States” means only “relatively permanent, standing or continuously the word “waters” in “waters of the United States” means only “relatively permanent, standing or continuously
flowing bodies of water”—that is, streams, rivers, and lakes.flowing bodies of water”—that is, streams, rivers, and lakes.1112 Wetlands could be included only when they have a Wetlands could be included only when they have a
“continuous surface connection” to such waters.“continuous surface connection” to such waters.1213
Justice Kennedy’s “Significant Nexus” Test: In a concurring opinion joined by no other Justice, Justice In a concurring opinion joined by no other Justice, Justice
Kennedy wrote that the Corps should determine on a case-by-case basis whether wetlands have a “significant Kennedy wrote that the Corps should determine on a case-by-case basis whether wetlands have a “significant
nexus” to traditionally navigable waters based on whether the wetland, either alone or in connection with similarly nexus” to traditionally navigable waters based on whether the wetland, either alone or in connection with similarly
situated properties, significantly impacts the chemical, physical, and biological integrity of a traditionally navigable situated properties, significantly impacts the chemical, physical, and biological integrity of a traditionally navigable
water.water.1314
In response to the rulings, the agencies developed guidance to help clarify how EPA and Corps In response to the rulings, the agencies developed guidance to help clarify how EPA and Corps
offices should implement the Court’s decisions. In particular, the agencies expressed the view that offices should implement the Court’s decisions. In particular, the agencies expressed the view that
waters meeting waters meeting either the relatively permanent standard articulated by Justice Scalia, the relatively permanent standard articulated by Justice Scalia, or the the
significant nexus standard articulated by Justice Kennedy, were subject to federal jurisdiction significant nexus standard articulated by Justice Kennedy, were subject to federal jurisdiction
under the act.under the act.1415 However, the Corps and EPA acknowledged that their written guidance did not However, the Corps and EPA acknowledged that their written guidance did not
provide the public or agency staff with the information needed to ensure timely, predictable, and provide the public or agency staff with the information needed to ensure timely, predictable, and
consistent jurisdictional determinations.consistent jurisdictional determinations.1516 Diverse stakeholders—including Members of Diverse stakeholders—including Members of
Congress, states, the regulated community, and nongovernmental organizations—requested a Congress, states, the regulated community, and nongovernmental organizations—requested a
formal rulemaking to revise the existing rules.formal rulemaking to revise the existing rules.1617
2015 Clean Water Rule
In 2015, the Corps and EPA issued the Clean Water Rule, which redefined WOTUS in the In 2015, the Corps and EPA issued the Clean Water Rule, which redefined WOTUS in the
agencies’ regulations for the first time since the 1980s.agencies’ regulations for the first time since the 1980s.1718 The Clean Water Rule retained aspects of The Clean Water Rule retained aspects of
the agencies’ earlier guidance and also incorporated new features, including a new definition of the agencies’ earlier guidance and also incorporated new features, including a new definition of
tributaries and definitions and criteria related to adjacency.tributaries and definitions and criteria related to adjacency.1819
Some stakeholders and observers viewed the Clean Water Rule as an expansion of CWA Some stakeholders and observers viewed the Clean Water Rule as an expansion of CWA
jurisdiction, while others argued that it excluded too many waters from federal jurisdiction.jurisdiction, while others argued that it excluded too many waters from federal jurisdiction.1920
Numerous parties challenged the Clean Water Rule, and some district courts issued preliminary Numerous parties challenged the Clean Water Rule, and some district courts issued preliminary
injunctions temporarily barring the Clean Water Rule from taking effect in certain states.injunctions temporarily barring the Clean Water Rule from taking effect in certain states.~~20 Two~~
~~courts also remanded the rule to the Corps and EPA, concluding that it violated the~~

1121 Two 12 Id. at 739. Id. at 739.
1213 Id. at 742. Id. at 742.
1314 Id. at 782 (Kennedy, J., concurring). Id. at 782 (Kennedy, J., concurring).
~~14 2008~~15 2008 Rapanos Guidance; see also Guidance; see also Rapanos, 547 U.S. at 810 (Stevens, J., dissenting). , 547 U.S. at 810 (Stevens, J., dissenting).
1516 2015 Clean Water Rule, p. 37056. 2015 Clean Water Rule, p. 37056.
1617 See EPA Web Archive at https://archive.epa.gov/epa/cleanwaterrule/what-clean-water-rule-does.html, which See EPA Web Archive at https://archive.epa.gov/epa/cleanwaterrule/what-clean-water-rule-does.html, which
includes a list of stakeholders requesting a rulemaking (https://archive.epa.gov/epa/sites/production/files/2014-03/includes a list of stakeholders requesting a rulemaking (https://archive.epa.gov/epa/sites/production/files/2014-03/
documents/wus_request_rulemaking.pdf). documents/wus_request_rulemaking.pdf).
1718 2015 Clean Water Rule. 2015 Clean Water Rule.
1819 2015 Clean Water Rule, pp. 37057-37059, 37105-37106. 2015 Clean Water Rule, pp. 37057-37059, 37105-37106.
1920 See, for example, Carolina Bolado, “Fla., Others Sue EPA, Corps Over Clean Water Act Expansion,” See, for example, Carolina Bolado, “Fla., Others Sue EPA, Corps Over Clean Water Act Expansion,” Law360, June , June
30, 2015; Center for Biological Diversity, “EPA and Army Corps Issue Weak Clean Water Rule,” press release, May 30, 2015; Center for Biological Diversity, “EPA and Army Corps Issue Weak Clean Water Rule,” press release, May
27, 2015, https://www.biologicaldiversity.org/news/press_releases/2015/clean-water-rule_05-27-2015.html. 27, 2015, https://www.biologicaldiversity.org/news/press_releases/2015/clean-water-rule_05-27-2015.html.
2021 North Dakota v. EPA, 127 F. Supp. 3d 1047 (D.N.D. 2015); Georgia v. Pruitt, 326 F. Supp. 3d 1356 (S.D. Ga. 2018); North Dakota v. EPA, 127 F. Supp. 3d 1047 (D.N.D. 2015); Georgia v. Pruitt, 326 F. Supp. 3d 1356 (S.D. Ga. 2018);
Texas v. EPA, No. 3:15-cv-162, 2018 WL 4518230 (S.D. Tex. Sept. 12, 2018); Or. Cattlemen’s Ass’n v. EPA, No. 19-Texas v. EPA, No. 3:15-cv-162, 2018 WL 4518230 (S.D. Tex. Sept. 12, 2018); Or. Cattlemen’s Ass’n v. EPA, No. 19-
00564 (D. Or. July 26, 2019). 00564 (D. Or. July 26, 2019).
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courts also remanded the rule to the Corps and EPA, concluding that it violated the Administrative Procedure Act (APA) and exceeded the agencies’ statutory authority under the Administrative Procedure Act (APA) and exceeded the agencies’ statutory authority under the
CWA.CWA.2122 As a result, until its rescission, the Clean Water Rule was in effect in a patchwork of As a result, until its rescission, the Clean Water Rule was in effect in a patchwork of
states. In states that were subject to a preliminary injunction or an order remanding the rule to the states. In states that were subject to a preliminary injunction or an order remanding the rule to the
Corps and EPA, the pre-2015 regulatory framework applied. Corps and EPA, the pre-2015 regulatory framework applied.
2020 Navigable Waters Protection Rule
The Trump Administration described the Clean Water Rule as an example of federal “overreach,” The Trump Administration described the Clean Water Rule as an example of federal “overreach,”
and the Corps and EPA engaged in a two-step process to rescind and revise it.and the Corps and EPA engaged in a two-step process to rescind and revise it.2223 In Step One, the In Step One, the
Corps and EPA rescinded the Clean Water Rule and recodified the pre-2015 regulations.Corps and EPA rescinded the Clean Water Rule and recodified the pre-2015 regulations.2324
Accordingly, the pre-2015 regulations and guidance were in effect beginning on the effective date Accordingly, the pre-2015 regulations and guidance were in effect beginning on the effective date
of the Step One Rule (December 23, 2019), and until the agencies’ redefinition of WOTUS went of the Step One Rule (December 23, 2019), and until the agencies’ redefinition of WOTUS went
into effect. In April 2020, the Corps and EPA published a final Step Two Rule to redefine into effect. In April 2020, the Corps and EPA published a final Step Two Rule to redefine
WOTUS, titled the Navigable Waters Protection Rule.WOTUS, titled the Navigable Waters Protection Rule.2425 The rule went into effect on June 22, The rule went into effect on June 22,
2020, replacing the Step One Rule. 2020, replacing the Step One Rule.
Overall, the Navigable Waters Protection Rule narrowed the scope of waters and wetlands that Overall, the Navigable Waters Protection Rule narrowed the scope of waters and wetlands that
were considered WOTUS (and were therefore under federal jurisdiction) compared to both the were considered WOTUS (and were therefore under federal jurisdiction) compared to both the
Clean Water Rule and the pre-2015 rules. As with the Clean Water Rule, the Navigable Waters Clean Water Rule and the pre-2015 rules. As with the Clean Water Rule, the Navigable Waters
Protection Rule prompted a range of reactions from a variety of stakeholders and resulted in Protection Rule prompted a range of reactions from a variety of stakeholders and resulted in
many lawsuits around the country. many lawsuits around the country.
President Biden signaled interest in reconsidering the Navigable Waters Protection Rule President Biden signaled interest in reconsidering the Navigable Waters Protection Rule
immediately upon taking office.immediately upon taking office.2526 After announcing in June 2021 that they intended to revise the After announcing in June 2021 that they intended to revise the
definition of WOTUS again, the Corps and EPA asked courts where legal challenges to the definition of WOTUS again, the Corps and EPA asked courts where legal challenges to the
Navigable Waters Protection Rule were pending to remand the rule while they developed a new Navigable Waters Protection Rule were pending to remand the rule while they developed a new
regulation.regulation.2627
On August 30, 2021, the U.S. District Court for the District of Arizona granted the agencies’ On August 30, 2021, the U.S. District Court for the District of Arizona granted the agencies’
request for voluntary remand, but also vacated the rule.request for voluntary remand, but also vacated the rule.2728 While the court did not issue a ruling on While the court did not issue a ruling on
the merits of the Navigable Waters Protection Rule, it found that both the plaintiffs and the United the merits of the Navigable Waters Protection Rule, it found that both the plaintiffs and the United

21States had identified concerns with the rule that involved fundamental, substantive, and incurable 22 Georgia v. Wheeler, 418 F. Supp. 3d 1336 (S.D. Ga. 2019); Texas v. EPA, 389 F. Supp. 3d 497 (S.D. Tex. 2019). In Georgia v. Wheeler, 418 F. Supp. 3d 1336 (S.D. Ga. 2019); Texas v. EPA, 389 F. Supp. 3d 497 (S.D. Tex. 2019). In
this context, to “remand” means to return the rule to the agencies to reconsider possible errors or defects in their action. this context, to “remand” means to return the rule to the agencies to reconsider possible errors or defects in their action.
A court order that remands a rule may or may not render the rule unenforceable during any further proceedings. A court order that remands a rule may or may not render the rule unenforceable during any further proceedings.
2223 For example, EPA, “EPA, U.S. Army Repeal 2015 Rule Defining ‘Waters of the United States’ Ending Regulatory For example, EPA, “EPA, U.S. Army Repeal 2015 Rule Defining ‘Waters of the United States’ Ending Regulatory
Patchwork,” Patchwork,” ~~September~~Sept. 12, 2019, https://www.epa.gov/newsreleases/epa-us-army-repeal-2015-rule-defining-waters- 12, 2019, https://www.epa.gov/newsreleases/epa-us-army-repeal-2015-rule-defining-waters-
united-states-ending-regulatory-patchwork. united-states-ending-regulatory-patchwork.
2324 Army Corps of Engineers and EPA, “Definition of ‘Waters of the United States’—Recodification of Pre-Existing Army Corps of Engineers and EPA, “Definition of ‘Waters of the United States’—Recodification of Pre-Existing
Rules,” 84Rules,” 84 Federal Register 56626, 56626, ~~October~~Oct. 22, 2019. 22, 2019.
2425 Army Corps of Engineers and EPA, “The Navigable Waters Protection Rule: Definition of ‘Waters of the United Army Corps of Engineers and EPA, “The Navigable Waters Protection Rule: Definition of ‘Waters of the United
States,’” 85States,’” 85 Federal Register 22250, 22250, ~~April~~Apr. 21, 2020. 21, 2020.
2526 Executive Order 13990, “Protecting Public Health and the Environment and Restoring Science to Tackle the Climate Executive Order 13990, “Protecting Public Health and the Environment and Restoring Science to Tackle the Climate
Crisis,” 86Crisis,” 86 Federal Register 7037-7043, 7037-7043, ~~January~~Jan. 20, 2021. 20, 2021.
2627 EPA, “EPA, Army Announce Intent to Revise Definition of WOTUS,” press release, June 9, 2021, at EPA, “EPA, Army Announce Intent to Revise Definition of WOTUS,” press release, June 9, 2021, at
https://www.epa.gov/newsreleases/epa-army-announce-intent-revise-definition-wotus (hereinafter “June 2021 Press https://www.epa.gov/newsreleases/epa-army-announce-intent-revise-definition-wotus (hereinafter “June 2021 Press
Release”); see also, e.g., Motion for Remand Without Vacatur, Conservation Law Found. v. EPA, No. 1:20-cv-10820 Release”); see also, e.g., Motion for Remand Without Vacatur, Conservation Law Found. v. EPA, No. 1:20-cv-10820
(D. Mass. June 6, 2021), ECF No. 112. (D. Mass. June 6, 2021), ECF No. 112.
2728 Pascua Yaqui Tribe v. EPA, 557 F. Supp. 3d 949 (D. Ariz. 2021). One other court subsequently vacated the Pascua Yaqui Tribe v. EPA, 557 F. Supp. 3d 949 (D. Ariz. 2021). One other court subsequently vacated the
Navigable Waters Protection Rule, adopting similar reasoning to the Navigable Waters Protection Rule, adopting similar reasoning to the Pascua Yaqui court. Memorandum Opinion and court. Memorandum Opinion and
Order, Navajo Nation v. Regan, No. 2:20-cv-00602 (D.N.M. Sept. 27, 2021), ECF No. 43. In this context, to “vacate” Order, Navajo Nation v. Regan, No. 2:20-cv-00602 (D.N.M. Sept. 27, 2021), ECF No. 43. In this context, to “vacate”
the rule means to declare it invalid, as if the rule had never been in effect. the rule means to declare it invalid, as if the rule had never been in effect.
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~~States had identified concerns with the rule that involved fundamental, substantive, and incurable~~
~~flaws.~~flaws.29 In response to the order, the Corps and EPA announced that they had halted In response to the order, the Corps and EPA announced that they had halted
implementation of the Navigable Waters Protection Rule and would interpret WOTUS consistent implementation of the Navigable Waters Protection Rule and would interpret WOTUS consistent
with the pre-2015 regulatory regime until further notice.with the pre-2015 regulatory regime until further notice.2830 How Does the 2023 WOTUS Rule Define WOTUS? On January 18, 2023, the Corps and EPA, under the Biden Administration, published a new rule (the 2023 WOTUS Rule) redefining WOTUS in the agencies’ regulations.31 The rule went into effect on March 20, 2023, but was immediately challenged. The rule is currently in effect in 23 states, while the pre-2015 regulations are in effect in the remaining states and as applied to a group of industry associations that are participating in the pending litigation (see “Which Rule Is in Effect Now?”)
~~How Does the 2023 WOTUS Rule Define WOTUS?~~
The Corps and EPAThe Corps and EPA ~~have~~ asserted that their intent in promulgating the 2023 WOTUS Rule was to asserted that their intent in promulgating the 2023 WOTUS Rule was to
redefine WOTUS in a durable regulation, updating the pre-2015 rules to reflect consideration of redefine WOTUS in a durable regulation, updating the pre-2015 rules to reflect consideration of
Supreme Court decisions, science, and the agencies’ experience and technical expertise.Supreme Court decisions, science, and the agencies’ experience and technical expertise.2932 Overall, Overall,
the definition of WOTUS in the 2023 WOTUS Rule is narrower in scope than the Clean Water the definition of WOTUS in the 2023 WOTUS Rule is narrower in scope than the Clean Water
Rule and broader than the Navigable Waters Protection Rule. Rule and broader than the Navigable Waters Protection Rule.
The 2023 WOTUS Rule is divided into three parts: jurisdictional waters (WOTUS), exclusions, The 2023 WOTUS Rule is divided into three parts: jurisdictional waters (WOTUS), exclusions,
and definitions. These parts are summarized below, and compared to the pre-2015 rules and and definitions. These parts are summarized below, and compared to the pre-2015 rules and
guidance. guidance.
Jurisdictional Waters (WOTUS)
The 2023 WOTUS Rule includes seven WOTUS categories The 2023 WOTUS Rule includes seven WOTUS categories (Table 1).
Table 1. Jurisdictional Waters (WOTUS) Under the 2023 WOTUS Rule
Regulatory
Category of
Text
WOTUS
Description
Paragraph
Traditional Navigable Waters, such as large rivers and lakes, which are, were, or could be used Traditional Navigable Waters, such as large rivers and lakes, which are, were, or could be used
(a)(1) (a)(1)
Waters Waters
in interstate or foreign commerce, including waters affected by tides. in interstate or foreign commerce, including waters affected by tides.
Territorial Seas Territorial Seas
The territorial seas are the belt of the seas extending three miles out The territorial seas are the belt of the seas extending three miles out
(a)(1) (a)(1)
from the coast. from the coast.
Interstate Waters Interstate Waters
Waters, such as rivers, lakes, streams, or wetlands that flow across or Waters, such as rivers, lakes, streams, or wetlands that flow across or
(a)(1) (a)(1)
form part of state boundaries. form part of state boundaries.
Impoundments of Impoundments of
Impounded waters created in or from jurisdictional waters, whether Impounded waters created in or from jurisdictional waters, whether
(a)(2) (a)(2)
Jurisdictional Waters Jurisdictional Waters
natural (e.g., beaver ponds) or artificial (e.g., reservoirs). natural (e.g., beaver ponds) or artificial (e.g., reservoirs).
~~Tributaries~~
~~Waters such as branches of creeks, streams, rivers, lakes, ponds, ditches,~~
~~(a)(3)~~
~~and impoundments that flow into traditional navigable waters, the~~
~~territorial seas, interstate waters, or impoundments of jurisdictional~~
~~waters. Tributaries are WOTUS if they meet either the relatively~~
~~permanent standard or the significant nexus standard as described further~~
~~in the 2023 WOTUS Rule.~~

28 29 Pascua Yaqui, 557 F. Supp. 3d at 955. 30 See EPA, “Definition of ‘Waters of the United States’: Rule Status and Litigation Update,” See EPA, “Definition of ‘Waters of the United States’: Rule Status and Litigation Update,” ~~December~~Dec. 30, 2022, 30, 2022,
https://www.epa.gov/wotus/definition-waters-united-states-rule-status-and-litigation-update. https://www.epa.gov/wotus/definition-waters-united-states-rule-status-and-litigation-update.
2931 2023 WOTUS Rule. 32 2023 WOTUS Rule, p. 3019; and 2022 WOTUS Fact Sheet. 2023 WOTUS Rule, p. 3019; and 2022 WOTUS Fact Sheet.
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Waters of the United States (WOTUS): Frequently Asked Questions

Regulatory
Category of
Text
WOTUS
Description
Paragraph
Tributaries Waters such as branches of creeks, streams, rivers, lakes, ponds, ditches, (a)(3) and impoundments that flow into traditional navigable waters, the territorial seas, interstate waters, or impoundments of jurisdictional waters. Tributaries are WOTUS if they meet either the relatively permanent standard or the significant nexus standard as described further in the 2023 WOTUS Rule. Adjacent Wetlands Adjacent Wetlands
Wetlands that are (1) adjacent to a traditional navigable water, the Wetlands that are (1) adjacent to a traditional navigable water, the
(a)(4) (a)(4)
territorial seas, or an interstate water; (2) adjacent and with a continuous territorial seas, or an interstate water; (2) adjacent and with a continuous
surface connection to either relatively permanent jurisdictional surface connection to either relatively permanent jurisdictional
impoundments or jurisdictional tributaries that meet the relatively impoundments or jurisdictional tributaries that meet the relatively
permanent standard; or (3) wetlands adjacent to jurisdictional permanent standard; or (3) wetlands adjacent to jurisdictional
impoundments or jurisdictional tributaries when the wetlands meet the impoundments or jurisdictional tributaries when the wetlands meet the
significant nexus standard. significant nexus standard.
Wetlands, defined in the rule, generally include swamps, marshes, bogs, Wetlands, defined in the rule, generally include swamps, marshes, bogs,
and similar areas. Adjacent is defined in the rule to mean “bordering, and similar areas. Adjacent is defined in the rule to mean “bordering,
contiguous, or neighboring.” The definition also specifies that wetlands contiguous, or neighboring.” The definition also specifies that wetlands
separated from other WOTUS by man-made dikes or barriers, natural separated from other WOTUS by man-made dikes or barriers, natural
river berms, beach dunes, and the like are “adjacent wetlands.” river berms, beach dunes, and the like are “adjacent wetlands.”
“Additional “Additional
Lakes, ponds, streams, or wetlands that do not fall under one of the other Lakes, ponds, streams, or wetlands that do not fall under one of the other
(a)(5) (a)(5)
waters”—intrastate waters”—intrastate
WOTUS categories. Such waters are jurisdictional if they meet either the WOTUS categories. Such waters are jurisdictional if they meet either the
lakes and ponds, lakes and ponds,
relatively permanent or significant nexus standard. relatively permanent or significant nexus standard.
streams, or wetlands streams, or wetlands
Sources: CRS analysis; 2023 WOTUS Rule; 2022 WOTUS Fact Sheet. CRS analysis; 2023 WOTUS Rule; 2022 WOTUS Fact Sheet.
Traditional Navigable Waters, the Territorial Seas and Interstate Waters
(Paragraph (a)(1) Waters)
The 2023 WOTUS Rule retains three categories without changes to the text or substance from The 2023 WOTUS Rule retains three categories without changes to the text or substance from
pre-2015 regulations.pre-2015 regulations.3033 These include the traditional navigable waters, the territorial seas, and These include the traditional navigable waters, the territorial seas, and
interstate waters. However, the agencies restructured the rule to streamline the regulatory text, interstate waters. However, the agencies restructured the rule to streamline the regulatory text,
and combined these three still-separate categories under one paragraph (i.e., (a)(1) waters) and combined these three still-separate categories under one paragraph (i.e., (a)(1) waters)
because, as the agencies explain in the rule’s preamble, the jurisdictional status of other because, as the agencies explain in the rule’s preamble, the jurisdictional status of other
categories of waters relies on their connection to waters from one of these three categories.categories of waters relies on their connection to waters from one of these three categories.3134
Impoundments of Jurisdictional Waters
The 2023 WOTUS Rule also retains the impoundments of jurisdictional waters category with one The 2023 WOTUS Rule also retains the impoundments of jurisdictional waters category with one
change from the pre-2015 regulations.change from the pre-2015 regulations.3235 The pre-2015 regulations included impoundments of any The pre-2015 regulations included impoundments of any
WOTUS, but the 2023 WOTUS Rule would exclude impoundments of waters determined to be WOTUS, but the 2023 WOTUS Rule would exclude impoundments of waters determined to be
jurisdictional under paragraph (a)(5), which the Corps and EPA in their fact sheet refer to as jurisdictional under paragraph (a)(5), which the Corps and EPA in their fact sheet refer to as
“additional waters.”“additional waters.”3336 These “additional waters” are a subset of what was previously referred to as These “additional waters” are a subset of what was previously referred to as
the “other waters” category. (See further discussion on “additional waters” below.) the “other waters” category. (See further discussion on “additional waters” below.)
~~Tributaries, Adjacent Wetlands, and “Additional Waters”~~
~~The remaining three categories—tributaries, adjacent wetlands, and “additional waters”—reflect~~
~~the definition of WOTUS from pre-2015 regulations, but include changes that the agencies assert~~

30 33 2023 WOTUS Rule, p. 3068. 2023 WOTUS Rule, p. 3068.
3134 Ibid. Ibid.
3235 2023 WOTUS Rule, pp. 3075-3076. 2023 WOTUS Rule, pp. 3075-3076.
3336 2023 WOTUS Rule, p. 3066; and 2022 WOTUS Fact Sheet, p. 2. Note that impoundments of (a)(5) waters may still 2023 WOTUS Rule, p. 3066; and 2022 WOTUS Fact Sheet, p. 2. Note that impoundments of (a)(5) waters may still
be determined to be jurisdictional if they meet the requirements of another category of WOTUS. be determined to be jurisdictional if they meet the requirements of another category of WOTUS.
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Waters of the United States (WOTUS): Frequently Asked Questions

Tributaries, Adjacent Wetlands, and “Additional Waters” The remaining three categories—tributaries, adjacent wetlands, and “additional waters”—reflect the definition of WOTUS from pre-2015 regulations, but include changes that the agencies assert reflect Supreme Court precedent, science, and their technical expertise.reflect Supreme Court precedent, science, and their technical expertise.3437 For example, the 2023 For example, the 2023
WOTUS Rule clarifies that the waters in these three categories may meet either the relatively WOTUS Rule clarifies that the waters in these three categories may meet either the relatively
permanent standard or the significant nexus standard for purposes of determining jurisdiction.permanent standard or the significant nexus standard for purposes of determining jurisdiction.3538
The Corps and EPA explained that this aspect of the 2023 WOTUS Rule is not an application or The Corps and EPA explained that this aspect of the 2023 WOTUS Rule is not an application or
interpretation of the multiple opinions in interpretation of the multiple opinions in Rapanos..3639 Instead, these standards are contained in the Instead, these standards are contained in the
2023 WOTUS Rule text and are informed by, but separate from, the two tests identified by the 2023 WOTUS Rule text and are informed by, but separate from, the two tests identified by the
Supreme Court. In addition, the agencies made certain changes to each of the categories that Supreme Court. In addition, the agencies made certain changes to each of the categories that
constrain which waters are jurisdictional, in comparison to the pre-2015 regulations. constrain which waters are jurisdictional, in comparison to the pre-2015 regulations.
• Tributaries: A tributary is considered a WOTUS under the 2023 WOTUS Rule if : A tributary is considered a WOTUS under the 2023 WOTUS Rule if
it is a tributary of a traditional navigable water, the territorial seas, an interstate it is a tributary of a traditional navigable water, the territorial seas, an interstate
water, or an impoundment of a jurisdictional water and also meets either the water, or an impoundment of a jurisdictional water and also meets either the
relatively permanent or significant nexus standard.relatively permanent or significant nexus standard.3740

As compared to the pre-2015 regulations, the 2023 WOTUS Rule adds the As compared to the pre-2015 regulations, the 2023 WOTUS Rule adds the
territorial seas to the list of waters to which a water may be a tributary. The territorial seas to the list of waters to which a water may be a tributary. The
agencies note that, in practice, this is not a significant change as most tributaries agencies note that, in practice, this is not a significant change as most tributaries
will reach a traditional navigable water before they reach the territorial seas.will reach a traditional navigable water before they reach the territorial seas.3841

The 2023 WOTUS Rule also deletes the “additional waters” category from the The 2023 WOTUS Rule also deletes the “additional waters” category from the
list of waters to which a water may be a tributary.list of waters to which a water may be a tributary.3942 The pre-2015 regulations The pre-2015 regulations
included the comparable “other waters” category on the list, and the “other included the comparable “other waters” category on the list, and the “other
waters” category itself was broader, as discussed below.waters” category itself was broader, as discussed below.4043

Similar to the pre-2015 regulations, the 2023 WOTUS rule does not contain a Similar to the pre-2015 regulations, the 2023 WOTUS rule does not contain a
definition of “tributary.”definition of “tributary.”4144 In addition, consistent with the pre-2015 regulations, In addition, consistent with the pre-2015 regulations,
the 2023 WOTUS rule does not include or exclude tributaries as WOTUS based the 2023 WOTUS rule does not include or exclude tributaries as WOTUS based
on their flow regime (i.e., meaning whether they flow year-round, seasonally, or on their flow regime (i.e., meaning whether they flow year-round, seasonally, or
only in response to precipitation events).only in response to precipitation events).42

3445 37 2023 WOTUS Rule, pp. 3005-3006; and 2022 WOTUS Fact Sheet. 2023 WOTUS Rule, pp. 3005-3006; and 2022 WOTUS Fact Sheet.
3538 Ibid. Ibid.
3639 2023 WOTUS Rule, p. 3022. 2023 WOTUS Rule, p. 3022.
3740 2023 WOTUS Rule, p. 3142. 2023 WOTUS Rule, p. 3142.
3841 2023 WOTUS Rule, pp. 3079-3080. 2023 WOTUS Rule, pp. 3079-3080.
3942 Ibid. Ibid.
4043 1986 Corps Rule, p. 41250. 1986 Corps Rule, p. 41250.
4144 2023 WOTUS Rule, pp. 3080-3081. Both the Clean Water Rule and the Navigable Waters Protection Rule included 2023 WOTUS Rule, pp. 3080-3081. Both the Clean Water Rule and the Navigable Waters Protection Rule included
a definition of “tributary.” In the preamble to the 2023 WOTUS Rule, the agencies concluded that a definition was not a definition of “tributary.” In the preamble to the 2023 WOTUS Rule, the agencies concluded that a definition was not
required because the agencies have decades of experience implementing the 1986 regulations, which also did not required because the agencies have decades of experience implementing the 1986 regulations, which also did not
include a definition. Further, the agencies assert that they “articulate and explain the agencies’ well-established include a definition. Further, the agencies assert that they “articulate and explain the agencies’ well-established
interpretation and practices for identifying tributaries” in the preamble. interpretation and practices for identifying tributaries” in the preamble.
4245 2023 WOTUS Rule, pp. 3080-3081. The rule’s preamble clarifies that “a tributary for purposes of this rule includes 2023 WOTUS Rule, pp. 3080-3081. The rule’s preamble clarifies that “a tributary for purposes of this rule includes
rivers, streams, lakes, ponds, and impoundments, regardless of their flow regime, that flow directly or indirectly rivers, streams, lakes, ponds, and impoundments, regardless of their flow regime, that flow directly or indirectly
through another water or waters to a traditional navigable water, the territorial seas, or an interstate water.” Note that through another water or waters to a traditional navigable water, the territorial seas, or an interstate water.” Note that
the Navigable Waters Protection Rule’s definition required that a tributary be the Navigable Waters Protection Rule’s definition required that a tributary be perennial (i.e., flow year-round) or (i.e., flow year-round) or
intermittent (i.e., flow continuously only during certain times of the year, such as seasonally) and excluded (i.e., flow continuously only during certain times of the year, such as seasonally) and excluded ephemeral
~~streams (i.e., those that flow only in response to precipitation events). The Clean Water Rule’s definition provided that~~
~~a tributary could be perennial, intermittent, or ephemeral as long as other criteria in the definition were met.~~(continued...)
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link to page 20 Waters of the United States (WOTUS): Frequently Asked Questions

• Adjacent wetlands: Under the 2023 WOTUS Rule, adjacent wetlands are Under the 2023 WOTUS Rule, adjacent wetlands are
considered WOTUS if (1) they are adjacent to traditional navigable waters, considered WOTUS if (1) they are adjacent to traditional navigable waters,
interstate waters, or the territorial seas; (2) they are adjacent to and with a interstate waters, or the territorial seas; (2) they are adjacent to and with a
continuous surface connection to jurisdictional impoundments or tributaries that continuous surface connection to jurisdictional impoundments or tributaries that
meet the relatively permanent standard; or (3) they are adjacent to jurisdictional meet the relatively permanent standard; or (3) they are adjacent to jurisdictional
impoundments or tributaries and meet the significant nexus standard.impoundments or tributaries and meet the significant nexus standard.4346 The pre- The pre-
2015 regulations more broadly included wetlands adjacent to waters in any of the 2015 regulations more broadly included wetlands adjacent to waters in any of the
WOTUS categories, other than wetlands themselves.WOTUS categories, other than wetlands themselves.4447 (Note that the 2008 Rapanos Guidance provided additional specifics as to which wetlands were WOTUS, as discussed in Table 2.) Thus, in comparison to the Thus, in comparison to the
pre-2015 regulations, the 2023 WOTUS Rule requires an additional pre-2015 regulations, the 2023 WOTUS Rule requires an additional
demonstration for wetlands adjacent to waters that are not (a)(1) waters, that the demonstration for wetlands adjacent to waters that are not (a)(1) waters, that the
wetlands have a continuous surface connection to a relatively permanent water or wetlands have a continuous surface connection to a relatively permanent water or
a significant nexus to an (a)(1) water.a significant nexus to an (a)(1) water.45
48 • “Additional waters”: Under the 2023 WOTUS Rule, intrastate lakes, ponds, Under the 2023 WOTUS Rule, intrastate lakes, ponds,
streams, or wetlands not identified in the other WOTUS categories similarly must streams, or wetlands not identified in the other WOTUS categories similarly must
meet either the relatively permanent standard or the significant nexus standard.meet either the relatively permanent standard or the significant nexus standard.4649
The agencies clarify that this category is substantially narrower than the non-The agencies clarify that this category is substantially narrower than the non-
exclusive list of “other waters” that was included under the pre-2015 exclusive list of “other waters” that was included under the pre-2015
regulations.regulations.4750 The agencies also replaced the broad Commerce Clause basis for The agencies also replaced the broad Commerce Clause basis for
jurisdiction from the pre-2015 regulations with the relatively permanent and jurisdiction from the pre-2015 regulations with the relatively permanent and
significant nexus standards.significant nexus standards.4851
Exclusions
The 2023 WOTUS Rule includes eight exclusions from the definition of WOTUS.The 2023 WOTUS Rule includes eight exclusions from the definition of WOTUS.4952 Some are Some are
long-standing exclusions for prior converted cropland and waste treatment systems that were long-standing exclusions for prior converted cropland and waste treatment systems that were
included in pre-2015 regulatory text. Others exclude features that were generally considered non-included in pre-2015 regulatory text. Others exclude features that were generally considered non-
jurisdictional under the pre-2015 regime, but were listed as such in preamble language and jurisdictional under the pre-2015 regime, but were listed as such in preamble language and
guidance rather than the regulatory text.guidance rather than the regulatory text.5053 Furthermore, these eight features were excluded in each Furthermore, these eight features were excluded in each
of the subsequent rules defining WOTUS (the Clean Water Rule and the Navigable Waters of the subsequent rules defining WOTUS (the Clean Water Rule and the Navigable Waters
Protection Rule), Protection Rule), ~~so the exclusions of the 2023 WOTUS Rule do not substantially change the~~
~~scope of federal jurisdiction.51 The~~ although the scope of some of these exclusions differed between rules.54 The exclusions include exclusions include
• Waste treatment systems, including treatment ponds or lagoons designed to , including treatment ponds or lagoons designed to
meet the requirements of the CWA; meet the requirements of the CWA;
~~ Prior converted cropland (see discussion below);~~
~~ Ditches (including roadside ditches), excavated wholly in and draining only dry~~
~~land and that do not carry a relatively permanent flow of water;~~

~~43 2023 WOTUS Rule, p. 3142.~~
~~44 1986 Corps Rule, p. 41250.~~
~~45 2023 WOTUS Rule, pp. 3090, 3142.~~
~~46 2023 WOTUS Rule, p. 3142.~~
~~47 2023 WOTUS Rule, p. 3097.~~
48 streams (i.e., those that flow only in response to precipitation events). The Clean Water Rule’s definition provided that a tributary could be perennial, intermittent, or ephemeral as long as other criteria in the definition were met. 46 2023 WOTUS Rule, p. 3142. 47 1986 Corps Rule, p. 41250. 48 2023 WOTUS Rule, pp. 3090, 3142. 49 2023 WOTUS Rule, p. 3142. 50 2023 WOTUS Rule, p. 3097. 51 Ibid. The pre-2015 regulatory framework included as jurisdictional waters “the use, degradation, or destruction of Ibid. The pre-2015 regulatory framework included as jurisdictional waters “the use, degradation, or destruction of
which could affect interstate or foreign commerce.” 1986 Corps Rule, p. 41250. which could affect interstate or foreign commerce.” 1986 Corps Rule, p. 41250.
4952 2023 WOTUS Rule, pp. 3066-3067 and 3142-3143. 2023 WOTUS Rule, pp. 3066-3067 and 3142-3143.
5053 Ibid. Ibid.
5154 2023 WOTUS Rule, p. 3103. See also 2015 Clean Water Rule, p. 37118; 2020 Navigable Waters Protection Rule, p. 2023 WOTUS Rule, p. 3103. See also 2015 Clean Water Rule, p. 37118; 2020 Navigable Waters Protection Rule, p.
22340. Note these exclusions were either explicitly listed, or were excluded under a broader exclusion category. 22340. Note these exclusions were either explicitly listed, or were excluded under a broader exclusion category.
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Waters of the United States (WOTUS): Frequently Asked Questions

• Prior converted cropland (see discussion below); • Ditches (including roadside ditches), excavated wholly in and draining only dry land and that do not carry a relatively permanent flow of water; • Artificially irrigated areas that would revert to dry land if the irrigation ceased; that would revert to dry land if the irrigation ceased;
• Artificial lakes or ponds created by excavating or diking dry land to collect and created by excavating or diking dry land to collect and
retain water and which are used exclusively for such purposes as stock watering, retain water and which are used exclusively for such purposes as stock watering,
irrigation, settling basins, or rice growing;irrigation, settling basins, or rice growing;
• Artificial reflecting pools or swimming pools or other small ornamental
bodies of water created by excavating or diking dry land to retain water for created by excavating or diking dry land to retain water for
primarily aesthetic reasons;primarily aesthetic reasons;
• Waterfilled depressions created in dry land incidental to construction activity created in dry land incidental to construction activity
and pits excavated in dry land for the purpose of obtaining fill, sand, or gravel and pits excavated in dry land for the purpose of obtaining fill, sand, or gravel
unless and until the construction is abandoned and the resulting body of water unless and until the construction is abandoned and the resulting body of water
meets the definition of WOTUS; and meets the definition of WOTUS; and
• Swales and erosional features (e.g., gullies, small washes) characterized by low (e.g., gullies, small washes) characterized by low
volume, infrequent, or short duration flow. volume, infrequent, or short duration flow.
Regarding prior converted cropland, in the 2023 WOTUS Rule, the agencies repromulgated the Regarding prior converted cropland, in the 2023 WOTUS Rule, the agencies repromulgated the
pre-2015 regulatory exclusion, but also made certain changes to the regulatory text in what the pre-2015 regulatory exclusion, but also made certain changes to the regulatory text in what the
agencies described as an effort to improve clarity and consistency with the implementation by the agencies described as an effort to improve clarity and consistency with the implementation by the
U.S. Department of Agriculture (USDA) of the Food Security Act of 1985, as amended.U.S. Department of Agriculture (USDA) of the Food Security Act of 1985, as amended.5255 The The
Food Security Act includes a provision (the “Swampbuster” exception) which requires USDA to Food Security Act includes a provision (the “Swampbuster” exception) which requires USDA to
make determinations about whether wetland areas qualify as prior converted cropland.make determinations about whether wetland areas qualify as prior converted cropland.5356 The new The new
regulatory text in the 2023 WOTUS Rule specifies that prior converted cropland designated by regulatory text in the 2023 WOTUS Rule specifies that prior converted cropland designated by
USDA is excluded. The regulatory text also clarifies that the exclusion would cease upon a USDA is excluded. The regulatory text also clarifies that the exclusion would cease upon a
change of use, meaning the area is no longer available for the production of agricultural change of use, meaning the area is no longer available for the production of agricultural
commodities.commodities.5457 This change aligns the WOTUS regulatory exclusion with the Swampbuster This change aligns the WOTUS regulatory exclusion with the Swampbuster
exception for prior converted cropland.exception for prior converted cropland.5558
Definitions
The 2023 WOTUS Rule includes six definitions. Five of the six definitions are unchanged from The 2023 WOTUS Rule includes six definitions. Five of the six definitions are unchanged from
the pre-2015 regulations, including the definitions for “wetlands,” “adjacent,” “high tide line,” the pre-2015 regulations, including the definitions for “wetlands,” “adjacent,” “high tide line,”
“ordinary high water mark,” and “tidal water.”“ordinary high water mark,” and “tidal water.”5659
The 2023 WOTUS Rule newly defines the term “significantly affect,” for purposes of The 2023 WOTUS Rule newly defines the term “significantly affect,” for purposes of
determining whether a water meets the significant nexus standard, to mean “a material influence determining whether a water meets the significant nexus standard, to mean “a material influence
on the chemical, physical, or biological integrity” of an (a)(1) water (i.e., traditional navigable on the chemical, physical, or biological integrity” of an (a)(1) water (i.e., traditional navigable
waters, the territorial seas, or interstate waters).waters, the territorial seas, or interstate waters).5760 The definition also identifies functions to be 55 2023 WOTUS Rule, pp. 3105-3107. 56 See CRS In Focus IF11136, Prior Converted Cropland Under the Clean Water Act, by Laura Gatz and Megan Stubbs for more information. 57 2023 WOTUS Rule, p. 3142. 58 2023 WOTUS Rule, pp. 3105-3107. 59 2023 WOTUS Rule, pp. 3067, 3143. 60 Ibid. Congressional Research Service 9 Waters of the United States (WOTUS): Frequently Asked Questions ~~The definition also identifies functions to be~~
assessed and factors to be considered in determining whether waters, either alone or in assessed and factors to be considered in determining whether waters, either alone or in
combination with similarly situated waters in the region, significantly affect an (a)(1) water.combination with similarly situated waters in the region, significantly affect an (a)(1) water.58

~~52 2023 WOTUS Rule, pp. 3105-3107.~~
~~53 See CRS In Focus IF11136, Prior Converted Cropland Under the Clean Water Act, by Laura Gatz and Megan~~
~~Stubbs for more information.~~
~~54 2023 WOTUS Rule, p. 3142.~~
~~55 2023 WOTUS Rule, pp. 3105-3107.~~
~~56 2023 WOTUS Rule, pp. 3067, 3143.~~
~~57 Ibid.~~
~~58 Ibid. Functions, as listed in the rule, include contribution of flow; trapping, transformation, filtering, and transport of~~
~~materials (including nutrients, sediment, and other pollutants); retention and attenuation of floodwaters and runoff;~~
~~modulation of temperature in paragraph (a)(1) waters; or provision of habitat and food resources for aquatic species in~~
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9

~~Waters of the United States (WOTUS): Frequently Asked Questions~~

~~Which Rule Is in Effect Now?~~
~~The 2023 WOTUS Rule is scheduled to take effect on March 20, 2023. Until the 2023 WOTUS~~
~~Rule takes effect, the pre-2015 regulatory framework applies, as it has since a federal district~~
~~court vacated the Navigable Waters Protection Rule in August 2021.59~~
~~Litigation could change which rule is in effect. Previous lawsuits challenging the Clean Water~~
~~Rule and the Navigable Waters Protection Rule resulted in preliminary injunctions and other~~
~~rulings that barred implementation of the challenged rule and resulted in a prior regulatory~~
~~framework returning to effect, at least in some places.60 Parties challenging the 2023 WOTUS~~
~~Rule have sought a preliminary injunction, which, if granted, could result in similar limitations on~~
~~the rule’s implementation.61~~
~~A change in regulatory regime does not result in the retroactive application of a new rule to all~~
~~potentially covered waters. In particular, the transition to the 2023 WOTUS Rule does not~~
~~necessarily invalidate approved jurisdictional determinations (or AJDs), which the Corps issues to~~
~~identify whether a particular parcel of land contains WOTUS, and which may be used in the~~
~~CWA permitting process.62 Approved jurisdictional determinations completed when the~~
~~Navigable Waters Protection Rule or pre-2015 regulatory framework was in effect will not be~~
~~reopened before their expiration date unless they satisfy specific criteria for revision.63~~
~~Additionally, enforcement actions for violations of the CWA are typically based on the statutory~~
~~and regulatory framework that was in effect at the time the violations occurred, even if the rule~~
~~has since changed.~~
~~Has the 2023 WOTUS Rule Been Challenged~~
~~in Court?~~
~~The litigation landscape is developing rapidly, but as of the date of this report, four pending~~
~~lawsuits challenge the 2023 WOTUS Rule.~~
~~The first two lawsuits were filed on January 18, 2023, and have been consolidated in the U.S.~~
~~District Court for the Southern District of Texas.64 First, the State of Texas argues that the rule~~
~~unlawfully expands the Corps and EPA’s jurisdiction beyond the bounds of the CWA, violates the~~
~~major questions doctrine65 because the CWA does not authorize the agencies to determine the~~

~~paragraph (a)(1) waters. Factors, as listed in the rule, include the distance from a paragraph (a)(1) water; hydrologic~~
~~factors such as the frequency, duration, magnitude, timing, and rate of hydrologic connections, including shallow~~
~~subsurface flow; the size, density, or number of waters that have been determined to be similarly situated; landscape~~
~~position and geomorphology; and climatological variables such as temperature, rainfall, and snowpack.~~
~~59 EPA, “Definition of ‘Waters of the United States’: Rule Status and Litigation Update,” December 30, 2022,~~
~~https://www.epa.gov/wotus/definition-waters-united-states-rule-status-and-litigation-update.~~
~~60 For a discussion of litigation regarding the 2015 Clean Water Rule, see 2023 WOTUS Rule, p. 3016.~~
~~61 Motion for Preliminary Injunction, Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex. Feb. 7, 2023), ECF No. 13; Motion~~
~~for Preliminary Injunction, Am. Farm Bureau Fed’n v. EPA, No. 3:23-cv-00020, (S.D. Tex. Feb. 7, 2023), ECF No. 15.~~
~~62 See 33 C.F.R. § 331.2.~~
~~63 See EPA, “Current Implementation of Waters of the United States,” January 18, 2023, https://www.epa.gov/wotus/~~
~~current-implementation-waters-united-states; and U.S. Army Corps of Engineers, Regulatory Guidance Letter No. 05-~~
~~02 (June 14, 2005).~~
~~64 Order, Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex. Feb. 13, 2023), ECF No. 27.~~
~~65 Under the major questions doctrine, an agency must provide clear congressional authorization in certain cases when~~
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~~Waters of the United States (WOTUS): Frequently Asked Questions~~

61 Which Rule Is in Effect Now? The 2023 WOTUS Rule went into effect on March 20, 2023. Litigation has changed which rule is in effect in some states, however. Two federal district courts have issued preliminary injunctions, and one court of appeals has issued an injunction pending appeal, that collectively bar implementation of the 2023 WOTUS Rule in 27 states.62 The injunction pending appeal also applies to several industry associations that are plaintiffs in that lawsuit, as well as to their members.63 In those states and as to those associations and their members, the Corps and EPA stated that they would interpret WOTUS “consistent with the pre-2015 regulatory regime.”64 61 Ibid. Functions, as listed in the rule, include contribution of flow; trapping, transformation, filtering, and transport of materials (including nutrients, sediment, and other pollutants); retention and attenuation of floodwaters and runoff; modulation of temperature in paragraph (a)(1) waters; or provision of habitat and food resources for aquatic species in paragraph (a)(1) waters. Factors, as listed in the rule, include the distance from a paragraph (a)(1) water; hydrologic factors such as the frequency, duration, magnitude, timing, and rate of hydrologic connections, including shallow subsurface flow; the size, density, or number of waters that have been determined to be similarly situated; landscape position and geomorphology; and climatological variables such as temperature, rainfall, and snowpack. 62 Memorandum Opinion and Order Granting Preliminary Injunction, Texas v. EPA, No. 3:23-cv-17 (S.D. Tex. Mar. 19, 2023), ECF No. 60; Order Granting Plaintiffs’ Motion for Preliminary Injunction, West Virginia v. EPA, No. 3:23-cv-00032 (D.N.D. Apr. 12, 2023), ECF No. 131; Order, Kentucky v. EPA, No. 23-5343 (6th Cir. May 10, 2023), ECF No. 24. 63 Order, Kentucky v. EPA, No. 23:5343 (6th Cir. May 10, 2023), ECF No. 24. 64 EPA, Definition of “Waters of the United States”: Rule Status and Litigation Update (last updated May 30, 2023), https://www.epa.gov/wotus/definition-waters-united-states-rule-status-and-litigation-update. Congressional Research Service 10 link to page 17 Waters of the United States (WOTUS): Frequently Asked Questions Figure 1. Status of 2023 WOTUS Rule as of June 22, 2023 Source: CRS. Note: The Corps and EPA are also interpreting WOTUS consistent with the pre-2015 framework for the industry association plaintiffs in Kentucky v. EPA, No. 23-5343 (E.D. Ky.), and for their members. The Supreme Court’s recent decision in Sackett v. EPA does not directly affect the status of the 2023 WOTUS Rule.65 The majority’s opinion nevertheless rejects jurisdictional interpretations that are reflected in the 2023 WOTUS Rule, so the continued viability of the rule is uncertain. The decision also raises uncertainty regarding prior regulatory frameworks, which all extended jurisdiction to more wetlands than are covered under the Sackett majority’s interpretation. Following the Court’s decision, the Corps and EPA stated that they “will interpret the phrase ‘waters of the United States’ consistent with the Supreme Court’s decision in Sackett,” but the agencies have not provided any information regarding that interpretation.66 A change in regulatory regime will not result in the retroactive application of a new rule to all potentially covered waters. In particular, the transition to the 2023 WOTUS Rule does not necessarily invalidate approved jurisdictional determinations (AJDs), which the Corps issues to identify whether a particular parcel of land contains WOTUS, and which may be used in the CWA permitting process.67 Approved jurisdictional determinations completed when the Navigable Waters Protection Rule or pre-2015 regulatory framework were in effect will not be reopened before their expiration date unless they satisfy specific criteria for revision.68 65 See infra, “How Does Sackett v. EPA Affect the Scope of CWA Jurisdiction?” 66 EPA, Definition of “Waters of the United States”: Rule Status and Litigation Update (last updated May 30, 2023), https://www.epa.gov/wotus/definition-waters-united-states-rule-status-and-litigation-update. 67 See 33 C.F.R. § 331.2. 68 See EPA, “Current Implementation of Waters of the United States,” Jan. 18, 2023, https://www.epa.gov/wotus/current-implementation-waters-united-states; and U.S. Army Corps of Engineers, Regulatory Guidance Letter No. 05-02 (June 14, 2005). Congressional Research Service 11 Waters of the United States (WOTUS): Frequently Asked Questions Additionally, enforcement actions for violations of the CWA are typically based on the statutory and regulatory framework that was in effect at the time the violations occurred, even if the rule has since changed. Has the 2023 WOTUS Rule Been Challenged in Court? Five pending lawsuits challenge the 2023 WOTUS Rule.69 While no court has issued a ruling on the merits, preliminary orders have limited the implementation of the 2023 WOTUS Rule for some states and plaintiffs. The first two lawsuits were filed on January 18, 2023, and have been consolidated in the U.S. District Court for the Southern District of Texas.70 In the first suit, the State of Texas argues that the rule unlawfully expands the Corps and EPA’s jurisdiction beyond the bounds of the CWA, violates the major questions doctrine71 because the CWA does not authorize the agencies to determine the scope of their own jurisdiction, intrudes upon state sovereignty, and violates due process by scope of their own jurisdiction, intrudes upon state sovereignty, and violates due process by
failing to provide adequate notice of what conduct is prohibited under the statute.failing to provide adequate notice of what conduct is prohibited under the statute.~~66 Second~~72 In the second suit, a , a
coalition of agricultural and industry groups argues that the rule is unsupported by law and coalition of agricultural and industry groups argues that the rule is unsupported by law and
scientific and economic evidence; violates the Commerce Clause, the Due Process Clause of the scientific and economic evidence; violates the Commerce Clause, the Due Process Clause of the
Fifth Amendment, the major questions doctrine, and the nondelegation doctrine;Fifth Amendment, the major questions doctrine, and the nondelegation doctrine;67 73 exceeds the exceeds the
Corps’ and EPA’s statutory authority; and unlawfully fails to include a regulatory flexibility Corps’ and EPA’s statutory authority; and unlawfully fails to include a regulatory flexibility
analysis.analysis.6874 An environmental group has intervened in the lawsuits in support of the Corps and An environmental group has intervened in the lawsuits in support of the Corps and
EPA.EPA.6975
Third, a group of 24 states has challenged the 2023 WOTUS Rule in the U.S. District Court for Third, a group of 24 states has challenged the 2023 WOTUS Rule in the U.S. District Court for
the District of North Dakota.the District of North Dakota.7076 In addition to arguments similar to those made by the Texas In addition to arguments similar to those made by the Texas
plaintiffs, the state plaintiffs allege that the rule violates the APA because the final rule is not a plaintiffs, the state plaintiffs allege that the rule violates the APA because the final rule is not a
“logical outgrowth” of the rule the agencies proposed in December 2021 and that the rule violates “logical outgrowth” of the rule the agencies proposed in December 2021 and that the rule violates
the Tenth Amendment by asserting federal jurisdiction over intrastate waters and lands that are the Tenth Amendment by asserting federal jurisdiction over intrastate waters and lands that are
ordinarily regulated by the states.ordinarily regulated by the states.7177 The agricultural and industry groups challenging the rule in 69 Prior rules defining WOTUS were the subject of numerous lawsuits filed by industry groups, environmental groups, and states. In 2018, the Supreme Court held that challenges to a rule defining WOTUS are typically governed by the APA and must be reviewed first in federal district court. Nat’l Ass’n of Mfrs. v. Dept’ of Def., 138 S. Ct. 617 (2018). That holding limited the degree to which the agencies, under rules of court procedure, can seek a single nationwide decision about the validity of the 2023 WOTUS Rule. 70 Order, Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex. Feb. 13, 2023), ECF No. 27. 71 Under the major questions doctrine, an agency must provide clear congressional authorization in certain cases when ~~The agricultural and industry groups challenging the rule in~~
~~Texas are also seeking to intervene in the North Dakota litigation in support of the state~~
~~plaintiffs.72~~
~~Finally, the Commonwealth of Kentucky has challenged the 2023 WOTUS Rule in the U.S.~~
~~District Court for the Eastern District of Kentucky, raising similar allegations to those made by~~
~~Texas and the other state plaintiffs.73~~
~~Both sets of plaintiffs in the Texas lawsuits, as well as the state plaintiffs in the North Dakota~~
~~lawsuit, have asked the courts to bar implementation of the 2023 WOTUS Rule while the~~
~~litigation is pending.74 The courts have not yet ruled on the motions. As in litigation over the 2015~~
~~and 2020 rules, the issuance of one or more preliminary injunctions would limit the applicability~~
~~of the rule and leave in place the prior regulatory framework where any such injunction was in~~
~~effect.~~
~~Other stakeholders could also challenge the 2023 WOTUS Rule. Consistent with the statute of~~
~~limitations for APA claims, potential litigants would generally be required to file suit within six~~

it seeks to decide an issue of major national significance. For additional background on the major questions doctrine, it seeks to decide an issue of major national significance. For additional background on the major questions doctrine,
see CRS In Focus IF12077, see CRS In Focus IF12077, The Major Questions Doctrine, by Kate R. Bowers. , by Kate R. Bowers.
6672 Complaint, Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex. Jan. 18, 2023), ECF No. 1. Complaint, Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex. Jan. 18, 2023), ECF No. 1.
6773 The nondelegation doctrine is the separation-of-powers principle that limits Congress’s ability to cede its legislative The nondelegation doctrine is the separation-of-powers principle that limits Congress’s ability to cede its legislative
power to other branches of government or nongovernmental entities. For further discussion of the nondelegation power to other branches of government or nongovernmental entities. For further discussion of the nondelegation
doctrine, see Nondelegation Doctrine, Constitution Annotated, https://constitution.congress.gov/browse/article-1/?doctrine, see Nondelegation Doctrine, Constitution Annotated, https://constitution.congress.gov/browse/article-1/?
anchor=I_S1_5#I_S1_5. anchor=I_S1_5#I_S1_5.
6874 First Amended Complaint, Am. Farm Bureau Fed’n v. EPA, No. 3:23-cv-00020 (S.D. Tex. Feb. 2, 2023), ECF No. 1. First Amended Complaint, Am. Farm Bureau Fed’n v. EPA, No. 3:23-cv-00020 (S.D. Tex. Feb. 2, 2023), ECF No. 1.
6975 Bayou City Waterkeeper Motion to Intervene, Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex. Feb. 9, 2023), ECF No. Bayou City Waterkeeper Motion to Intervene, Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex. Feb. 9, 2023), ECF No.
20; Bayou City Waterkeeper Motion to Intervene, Am. Farm Bureau Fed’n v. EPA, No. 3:23-cv-00020 (S.D. Tex. Feb. 20; Bayou City Waterkeeper Motion to Intervene, Am. Farm Bureau Fed’n v. EPA, No. 3:23-cv-00020 (S.D. Tex. Feb.
9, 2023), ECF No. 16; Order, Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex. Feb. 14, 2023), ECF No. 30. 9, 2023), ECF No. 16; Order, Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex. Feb. 14, 2023), ECF No. 30.
7076 Complaint, West Virginia v. EPA, No. 3:23-cv-00032 (D.N.D. Feb. 16, 2023), ECF No. 1. Complaint, West Virginia v. EPA, No. 3:23-cv-00032 (D.N.D. Feb. 16, 2023), ECF No. 1.
~~71 Ibid.~~
~~72 Motion to Intervene of Proposed Business Intervenors, West Virginia v. EPA, No. 3:23-cv-00032 (D.N.D. Feb. 22,~~
~~2023), ECF No. 54.~~
~~73 Complaint, Kentucky v. EPA, No. 3:23-cv-00007 (E.D. Ky. Feb. 22, 2023), ECF No. 1.~~
7477 Id. Congressional Research Service 12 Waters of the United States (WOTUS): Frequently Asked Questions Texas have also intervened in the North Dakota litigation in support of the state plaintiffs, although the Corps and EPA have appealed the district court’s order granting the groups’ motion to intervene.78 Fourth, the Commonwealth of Kentucky has challenged the 2023 WOTUS Rule in the U.S. District Court for the Eastern District of Kentucky, raising similar allegations to those made by Texas and the other state plaintiffs.79 A fifth suit, filed in the Eastern District of Kentucky by a coalition of industry associations, was consolidated with the Commonwealth of Kentucky’s lawsuit.80 The plaintiffs in each lawsuit filed motions asking the courts to bar implementation of the 2023 WOTUS Rule while the litigation is pending.81 Two district courts have granted the motions and issued preliminary injunctions: The Texas district court granted Texas and Idaho’s motion, and the North Dakota district court granted the state plaintiffs’ motion.82 In granting Texas and Idaho’s motion, the Texas district court noted that the 2023 WOTUS Rule’s extended the significant nexus standard beyond the breadth intended by Justice Kennedy in Rapanos and identified potential constitutional problems with the rule’s coverage of all interstate waters.83 The court denied the Texas industry plaintiffs’ request for a nationwide injunction, however, holding that the industry associations had not demonstrated that they were entitled to injunctive relief beyond what was granted to the states.84 In granting the state plaintiffs’ motion for preliminary injunction, the North Dakota court agreed with the Texas court’s analysis, expressed concerns about the 2023 Rule’s treatment of tributaries and impoundments, and indicated that the agencies’ interpretation was likely in excess of their statutory authority, arbitrary and capricious, and in conflict with various constitutional limitations.85 The North Dakota district court has not yet ruled on the industry plaintiffs’ motion. The Corps and EPA have appealed both the Texas and North Dakota preliminary injunctions.86 The litigation in Kentucky has proceeded differently. In March 2023, the Kentucky district court denied both preliminary injunctions without prejudice and dismissed Kentucky and the industry plaintiffs’ claims.87 While the court noted that the plaintiffs’ allegations “may very well present a federal cause of action” in the future, their alleged injuries were too speculative and generalized to support their claims of standing and ripeness.88 Both Kentucky and the industry plaintiffs 78 Order and Federal Defendants’ Appeal from the Magistrate Judge’s Order Granting Industry’s Motion to Intervene, West Virginia v. EPA (D.N.D. March 22, 2023 and Apr. 5, 2023), ECF Nos. 110 and 129. 79 Complaint, Kentucky v. EPA, No. 3:23-cv-00007 (E.D. Ky. Feb. 22, 2023), ECF No. 1. 80 Complaint, Kentucky Chamber of Commerce v. EPA, No. 3:23-cv-00008 (E.D. Ky. Feb. 22, 2023); Order, Kentucky v. EPA, No. 3:23-cv-00007 (E.D. Ky. Feb. 28, 2023), ECF No. 16. 81 Motion for Preliminary Injunction, Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex. Feb. 7, 2023), ECF No. 13; Motion Motion for Preliminary Injunction, Texas v. EPA, No. 3:23-cv-00017 (S.D. Tex. Feb. 7, 2023), ECF No. 13; Motion
for Preliminary Injunction, Am. Farm Bureau Fed’n v. EPA, No. 3:23-cv-00020 (S.D. Tex. Feb. 7, 2023), ECF No. 15; for Preliminary Injunction, Am. Farm Bureau Fed’n v. EPA, No. 3:23-cv-00020 (S.D. Tex. Feb. 7, 2023), ECF No. 15;
Plaintiff States’ Motion for Preliminary Injunction, West Virginia v. EPA, No. 3:23-cv-00032 (D.N.D. Feb. 21, 2023), Plaintiff States’ Motion for Preliminary Injunction, West Virginia v. EPA, No. 3:23-cv-00032 (D.N.D. Feb. 21, 2023),
ECF No. 44ECF No. 44; Motions for Preliminary Injunction, Kentucky v. EPA, No. 3:23-cv-00007 (E.D. Ky. Feb. 23 and Feb. 28, 2023), ECF Nos. 10 and 17. 82 Memorandum Opinion and Order Granting Preliminary Injunction, Texas v. EPA, No. 3:23-cv-00017 (E.D. Tex. Mar. 19, 2023), ECF No. 60; Order Granting Plaintiffs’ Motion for Preliminary Injunction, West Virginia v. EPA (D.N.D. Apr. 12, 2023), ECF No. 131. 83 Memorandum Opinion and Order Granting Preliminary Injunction at 19-26, Texas v. EPA. 84 Id. at 34. 85 Order Granting Plaintiffs’ Motion for Preliminary Injunction at 17-29, West Virginia v. EPA. 86 Texas v. EPA, No. 23-40306 (5th Cir. 2023), West Virginia v. EPA, No. 23-2411 (8th Cir. 2023). 87 Opinion and Order, Kentucky v. EPA, No. 3:23-cv-00007 (E.D. Ky. Mar. 31, 2023), ECF No. 51. 88 Id. at 1. Congressional Research Service 13.
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~~Waters of the United States (WOTUS): Frequently Asked Questions~~

~~years after their claim accrues.75 Early lawsuits are the most likely to be closely watched, as they~~
~~will be the courts’ first opportunities to issue rulings that may be binding in later cases, and~~
~~because they will occur before the regulated public has substantially relied on the rule.~~
~~Prior rules defining WOTUS were the subject of numerous lawsuits filed by industry groups,~~
~~environmental groups, and states. In 2018, the Supreme Court held that challenges to a rule~~
~~defining WOTUS are typically governed by the APA and must be reviewed first in federal district~~
~~court.76 That holding limited the degree to which the agencies, under rules of court procedure, can~~
~~seek a single nationwide decision about the validity of the 2023 WOTUS Rule.~~
~~A case currently pending before the Supreme Court could also affect the definition of WOTUS. In~~
Sackett v. EPA, landowners challenging a particular compliance order have asked the Court more
~~broadly~~ Waters of the United States (WOTUS): Frequently Asked Questions appealed those rulings to the U.S. Court of Appeals for the Sixth Circuit and sought a stay of the district court’s decision pending appeal. In May 2023, the Sixth Circuit granted an injunction pending appeal, holding that the plaintiffs’ general allegations of injury were likely sufficient at this stage of litigation.89 As a result of the preliminary injunctions and injunction pending appeal, the pre-2015 framework is in effect in 27 states and as applied to the Kentucky industry plaintiffs and their members. Further proceedings in any of the pending lawsuits—or any newly filed lawsuits—could increase or decrease the number of states in which the 2023 WOTUS Rule is in effect.90 It is also likely that further proceedings within the context of the pending lawsuits will address the effect of the Supreme Court’s ruling in Sackett on the continued viability of the 2023 WOTUS Rule. How Does Sackett v. EPA Affect the Scope of CWA Jurisdiction? On May 25, 2023, the Supreme Court decided Sackett v. EPA, a case with significant implications for the scope of federal jurisdiction under the CWA.91 In Sackett, landowners in Idaho challenged a compliance order and asked the Court to revisit to revisit Rapanos and adopt Justice Scalia’s plurality test for determining whether and adopt Justice Scalia’s plurality test for determining whether
certain adjacent wetlands are WOTUS.certain adjacent wetlands are WOTUS.~~77 The~~ Applying the significant nexus test articulated by Justice Kennedy in Rapanos, the U.S. Court of Appeals for the Ninth Circuit upheld U.S. Court of Appeals for the Ninth Circuit upheld
EPA’s conclusion that the Sacketts’ property contained WOTUS that were subject to federal EPA’s conclusion that the Sacketts’ property contained WOTUS that were subject to federal
~~jurisdiction under the CWA and relevant regulations.78 EPA has argued that the Court should~~
~~continue to allow the use of Justice Kennedy’s significant nexus test to identify covered~~
~~wetlands.79~~
~~The Supreme Court held oral argument in Sackett on October 3, 2022, and a decision is expected~~
~~later this term. Although no agency regulation is presented for the Court’s review in Sackett, a~~
~~decision from the Court could affect the implementation or future judicial review of the 2023~~
~~WOTUS Rule, particularly with respect to the rule’s provisions regarding the jurisdiction of~~
~~adjacent wetlands. Additionally, although the Corps and EPA stated in the 2023 WOTUS Rule~~
~~preamble that their interpretation of the CWA is “not an interpretation of the multiple opinions in~~
Rapanos,”80 a Supreme Court holding that considers the continued viability of the standards
~~outlined in Rapanos would be relevant to the corresponding relatively permanent and significant~~
~~nexus tests that the agencies incorporated into the 2023 WOTUS Rule.~~
~~What Options Are Available to Congress Regarding~~
~~the Definition of WOTUS?~~
~~Considering the numerous court rulings, ongoing legal challenges, and issues that successive~~
~~administrations have faced in defining the scope of WOTUS, some stakeholders have urged~~
~~Congress to more specifically define the term through amendments to the CWA. Others argue that~~
~~the Corps and EPA, with their specific knowledge and expertise, are in the best position to~~
~~determine the scope of the term.~~
~~Congress can also stop agency rulemaking or regulatory enforcement through provisions added to~~
~~agency appropriations legislation. Such appropriations provisions could include (1) restrictions on~~
~~the finalization of particular proposed rules, (2) restrictions on regulatory activity within certain~~

~~75 28 U.S.C. § 2401(a).~~
~~76 Nat’l Ass’n of Mfrs. v. Dep’t of Def., 138 S. Ct. 617 (2018).~~
~~77 Sackett v. EPA, cert. granted, 142 S. Ct. 896 (No. 21-454) (U.S. Jan. 24, 2022).~~
~~78 Sackett v. EPA, 8 F.4th 1075 (9th Cir. 2021).~~
~~79 Brief for Respondents at 31, 33–34, 35, Sackett v. EPA, No. 21-454 (U.S. June 10, 2022).~~
~~80 2023 WOTUS Rule, p. 3021.~~
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~~Waters of the United States (WOTUS): Frequently Asked Questions~~

~~areas, (3) implementation or enforcement restrictions, and (4) conditional restrictions (e.g.,~~
~~preventing implementation of a rule until certain actions are taken).81~~
~~The scope of WOTUS has continued to be of interest in the 118th Congress. On February 8, 2023,~~
~~the House Transportation and Infrastructure Committee’s Subcommittee on Water Resources and~~
~~Environment held a hearing regarding the 2023 WOTUS Rule.82 Additionally, 152 Members of~~
~~the House of Representatives and 49 Senators sponsored or consponsored joint resolutions that~~
~~would disapprove the 2023 WOTUS Rule.83 The resolutions were introduced under the~~
~~Congressional Review Act (CRA), a law that allows Congress to overturn certain agency actions~~
~~in the form of a joint resolution of disapproval.84 Under the CRA, if both houses pass a joint~~
~~resolution for disapproval, it is sent to the President for signature or veto. If the President were to~~
~~veto a resolution, Congress could vote to override the veto with a two-thirds majority in both~~
~~chambers. If a joint resolution of disapproval is submitted within the CRA-specified deadline,~~
~~passed by Congress, and signed by the President (or if Congress votes to override a presidential~~
~~veto), the disapproved rule “shall not take effect (or continue),” and would be deemed not to have~~
~~had any effect at any time. Furthermore, if a joint resolution of disapproval is enacted, the CRA~~
~~provides that a rule may not be issued in “substantially the same form” as the disapproved rule~~
~~unless it is specifically authorized by a subsequent law.~~
~~In the 117th and 116th Congresses, some Members introduced legislation related to the scope of~~
~~WOTUS. Some of these bills would have enacted the Navigable Waters Protection Rule’s~~
~~definition of WOTUS into law, or amended the CWA to add a narrower definition of~~ ~~navigable~~
~~waters.85 Other bills introduced prior to the vacatur of the Navigable Waters Protection Rule or~~

~~81 CRS Report RL32240, The Federal Rulemaking Process: An Overview, coordinated by Maeve P. Carey.~~
~~82 U.S. Congress, House Committee on Transportation and Infrastructure, Subcommittee on Water Resources and~~
~~Environment,~~ ~~Hearing on Stakeholder Perspectives on Impacts of the Biden Administration’s Waters of the United~~
~~States (WOTUS) Rule, 118th Cong., 1st sess., February 8, 2021.~~
~~83 H.J.Res. 27 (118th Cong.); S.J.Res. 7 (118th Cong.).~~
~~84 5 U.S.C. § 801. For additional information about the CRA, see CRS Report R43992,~~ ~~The Congressional Review Act~~
~~(CRA): Frequently Asked Questions, by Maeve P. Carey and Christopher M. Davis.~~
~~85 For example, Withstanding Attempts to Encroach on our Resources (WATER) Act, H.R. 2660 (117th Congress);~~
~~H.Res. 318 (117th Congress); S.Res. 17 (117th Congress); Define WOTUS Act of 2021, H.R. 4570 and S. 2168 ((117th~~
~~Congress); Defense of Environment and Property Act of 2021, H.R. 5849 and S. 2517 (117th Congress); Navigable~~
~~Waters Protection Act of 2022, S. 3456 (117th Congress). Because WOTUS is a statutory phrase that defines~~ ~~navigable~~
~~waters, a different definition of the latter term could obviate the need to interpret the former, though it could introduce~~
~~new interpretive questions.~~
~~Congressional Research Service~~

13

~~Waters of the United States (WOTUS): Frequently Asked Questions~~

~~the repeal of the Clean Water Rule addressed the implementation of those rules, respectively.86~~
~~Additionally, committees in the 117th and 116th Congresses held hearings regarding WOTUS.87~~
~~Moving forward, Congress may oversee the Biden Administration’s implementation of the~~
~~revised definition, or may consider introducing legislation that provides a definition of WOTUS~~
~~or expresses a clearer intent as to how Congress believes the term should be defined.~~

~~Author Information~~

~~Kate R. Bowers~~
~~Laura Gatz~~
~~Legislative Attorney~~
~~Specialist in Environmental Policy~~

~~Disclaimer~~
~~This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan~~
~~shared staff to congressional committees and Members of Congress. It operates solely at the behest of and~~
~~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~~
~~connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not~~
~~subject to copyright protection in the United States. Any CRS Report may be reproduced and distributed in~~
~~its entirety without permission from CRS. However, as a CRS Report may include copyrighted images or~~
~~material from a third party, you may need to obtain the permission of the copyright holder if you wish to~~
~~copy or otherwise use copyrighted material.~~

~~86 E.g., Clean Water for All Act, H.R. 6745 (116th Congress); Federal Regulatory Certainty for Water Act, H.R. 2287~~
~~(116th Congress); Regulatory Certainty for Navigable Waters Act, H.R. 667 (116th Congress).~~
~~87 U.S. Congress, House Committee on Appropriations, Subcommittee on Interior, Environment, and Related Agencies,~~
Hearing on the Fiscal Year 2023 Budget Request for the Environmental Protection Agency, 117th Cong., 2nd sess.,
~~April 29, 2022. U.S. Congress, Senate Committee on Environment and Public Works,~~ ~~Hearing on Fiscal Year 2023~~
~~Environmental Protection Agency Budget, 117th Cong., 2nd sess., April 6, 2022. U.S. Congress, House Committee on~~
~~Transportation and Infrastructure, Subcommittee on Water Resources and Environment,~~ ~~President Biden’s Fiscal Year~~
~~2022 Budget Request: Agency Policies and Perspectives (Part II), 117th Cong., 1st sess., July 14, 2021. U.S. Congress,~~
~~House Committee on Transportation and Infrastructure, Subcommittee on Water Resources and Environment,~~
President Biden’s Fiscal Year 2022 Budget Request: Agency Policies and Perspectives (Part I), 117th Cong., 1st sess.,
~~June 24, 2021. U.S. Congress, Senate Committee on Environment and Public Works,~~ ~~Hearing on the Nomination of~~
~~Michael S. Regan to be Administrator of the Environmental Protection Agency, 117th Cong., 1st sess., February 3, 2021,~~
~~S.Hrg. 117-1;~~jurisdiction under the CWA and relevant regulations.92 On review, the Supreme Court unanimously reversed the Ninth Circuit. Although all nine Justices agreed that the lower court applied the wrong standard for identifying WOTUS, the Court was split 5-4 on the appropriate test. In an opinion authored by Justice Alito, the majority formally adopted the approach taken by the Rapanos plurality. The majority held that “waters” under the CWA are limited to “relatively permanent, standing or continuously flowing bodies of water forming geographic[al] features that are described in ordinary parlance as streams, oceans, rivers, and lakes.”93 The majority also held that the CWA covers only wetlands that qualify as WOTUS “in their own right.”94 This limited covered wetlands to those that are “indistinguishably part of a body of water that itself constitutes ‘waters’ under the CWA.”95 Quoting the Rapanos plurality, the majority concluded that WOTUS includes “only those wetlands that are as a practical matter indistinguishable from waters of the United States, such that it is difficult to determine where the water ends and the wetland begins. That occurs when wetlands have a continuous surface connection to bodies that are waters of the United States in their own right, so that there is no clear demarcation between waters and wetlands.”96 Accordingly, the majority ruled that CWA 89 Order, Kentucky v. EPA, No. 23-5343 (6th Cir. May 10, 2023), ECF No. 24. 90 Consistent with the statute of limitations for APA claims, potential litigants would generally be required to file suit within six years after their claims accrue. 28 U.S.C. § 2401(a). While additional lawsuits are thus possible, early lawsuits are the most likely to be closely watched, as they present the courts’ first opportunities to issue rulings that may be binding in later cases. 91 Sackett v. EPA, No. 21-454 (U.S. May 25, 2023). For a more in-depth discussion of Sackett, see CRS Legal Sidebar LSB10981, Supreme Court Narrows Federal Jurisdiction Under Clean Water Act, by Kate R. Bowers. 92 Sackett v. EPA, 8 F.4th 1075 (9th Cir. 2021). 93 Sackett v. EPA, No. 21-454, slip op. at 14 (U.S. May 25, 2023). 94 Id. at 19. 95 Id. at 22. 96 Id. at 21. Congressional Research Service 14 Waters of the United States (WOTUS): Frequently Asked Questions jurisdiction excludes wetlands that are neighboring to but separate from traditional navigable waters.97 In addition to reaffirming the Rapanos plurality’s standard, the majority also rejected the significant nexus test.98 The majority noted that Congress must “enact exceedingly clear language if it wishes to significantly alter the balance between federal and state power and the power of the Government over private property” and further reasoned that the significant nexus test “gives rise to serious vagueness concerns in light of the CWA’s criminal penalties.”99 According to the majority, the significant nexus test thus amounted to a “freewheeling inquiry” that “provides little notice to landowners of their obligations under the CWA.”100 The Court’s ruling narrows the scope of jurisdiction under the CWA as compared to its long-standing regulatory implementation and narrows the interpretation adopted by lower courts post-Rapanos. While the precise extent of the change will depend on how the Corps and EPA implement various aspects of the decision, the majority’s exclusion of wetlands that are separated from covered waters by natural or artificial barriers means that fewer wetlands will be covered than under any regulatory framework developed by the Corps or EPA since the 1970s.101 Additionally, the majority’s definition of waters appears to exclude ephemeral waters, thus narrowing the scope of waters as compared to the 2023 WOTUS Rule, the 2015 Clean Water Rule, and the pre-2015 regulations and guidance. Neither the 2023 Rule nor any prior regulation was presented to the Supreme Court for review in Sackett, so the Court’s decision does not automatically affect the status of the 2023 WOTUS Rule. The majority opinion nevertheless rejects jurisdictional interpretations that are reflected in the 2023 WOTUS Rule, so the continued viability of the rule is uncertain. The viability of the pre-2015 framework—to which the Corps and EPA have reverted in some parts of the country due to court orders temporarily barring implementation of the 2023 WOTUS Rule—is also uncertain, as the pre-2015 operative definition of WOTUS included more wetlands than are covered under the Sackett majority’s interpretation. Following the Court’s decision, the Corps and EPA issued a statement that they will “interpret the phrase ‘waters of the United States’ consistent with the Supreme Court’s decision in Sackett” and “continue to review the decision to determine next steps.”102 While the nature of those next steps remains to be seen, delays in CWA permitting and other CWA actions are possible. Following Rapanos, the Corps urged its district offices to delay issuing AJDs for areas beyond the limits of the traditional navigable waters until the agencies issued final guidance interpreting WOTUS in light of the Supreme Court’s decision.103 Following Sackett, at least one Corps district office has delayed issuing AJDs until further notice.104 The Supreme Court’s ruling could also affect regulation of waters at the state level. The CWA expressly reserves to states the right to issue more stringent regulations, and states may choose to 97 Id. at 25. 98 Id. at 22. 99 Id. at 24. 100 Id. at 25. 101 Sackett v. EPA, No. 21-454, slip op. at 6 (U.S. May 25, 2023) (Kavanaugh, J., concurring in the judgment). 102 EPA, Definition of “Waters of the United States”: Rule Status and Litigation Update (last updated May 30, 2023), https://www.epa.gov/wotus/definition-waters-united-states-rule-status-and-litigation-update. 103 U.S. Army Corps of Engineers, Interim Guidance on the Rapanos and Carabell Supreme Court Decision (July 5, 2006). 104 U.S. Army Corps of Engineers, Chicago District Website, Jurisdictional Determinations, https://www.lrc.usace.army.mil/Missions/Regulatory/Jurisdictional-Determinations/ (last visited June 15, 2023). Congressional Research Service 15 link to page 20 Waters of the United States (WOTUS): Frequently Asked Questions cover more waters in their own programs.105 Some states regulate waters within their borders beyond the scope of federal jurisdiction and have indicated that they plan to continue or expand such protections following Sackett.106 Other states have enacted laws barring environmental state agencies from promulgating regulations beyond what is federally required.107 A narrowed definition of WOTUS at the federal level could thus result in greater state-level divergence in the scope of covered waters. How Have Adjacent Wetlands Been Addressed in Prior WOTUS Regulations? The Corps and EPA have long included adjacent wetlands as their own category in the regulations they have promulgated to define WOTUS. While some rules included a more expansive definition and others narrower definitions of adjacent wetlands, all of the rules have recognized adjacent wetlands as WOTUS. These rules have provided that wetlands separated from other WOTUS by “man-made dikes or barriers, natural river berms, beach dunes and the like” are adjacent wetlands.108 The scope of adjacent wetlands in the Sackett decision, as previously discussed, diverges from long-standing regulations and practice by excluding wetlands separated from WOTUS. Table 2 summaries the scope of adjacent wetlands in the pre-2015 regulations, the 2015 Clean Water Rule, the 2020 Navigable Waters Protection Rule, the 2023 WOTUS Rule, and the Sackett v. EPA decision. 105 33 U.S.C. § 1370. 106 E.g., California State Water Resources Control Board, press release, State Water Board Statement: U.S. Supreme Court decision decreases federal wetlands protection (May 25, 2023), https://waterboards.ca.gov/press_room/press_releases/2023.html. 107 See Corps and EPA, Resource and Programmatic Assessment for the Navigable Waters Protection Rule: Definition of "Waters of the United States," January 23, 2020, p. 45-46, https://www.epa.gov/sites/production/files/2020-01/documents/rpa_-_nwpr_.pdf. Environmental Law Institute, State Constraints: State-Imposed Limitations on the Authority of Agencies to Regulate Waters Beyond the Scope of the Federal Clean Water Act, May 2013, p. 1, https://www.eli.org/sites/default/files/eli-pubs/d23-04.pdf. 108 E.g., Army Corps of Engineers, “Final Rule for Regulatory Programs of the Corps of Engineers,” 51 Federal Register 41206, 412501, Nov. 13, 1986 (1986 Corps Rule). Congressional Research Service 16 link to page 22 link to page 22 link to page 22 Table 2. Scope of Adjacent Wetlands Under Waters of the United States (WOTUS) Regulations, Guidance, and in the Sackett v. EPA Decision Description of the Adjacent Wetlands WOTUS Definition of Adjacent Source Category Pre-2015 Wetlands adjacent to other jurisdictional waters other • Bordering, contiguous, or neighboringb Regulationsa than waters that are themselves wetlands • Wetlands separated from other waters of the United States by man-made dikes or barriers, natural river berms, beach dunes, and the like are “adjacent wetlands” 2008 Rapanos • Wetlands that were adjacent to traditional Provided that adjacency was established by satisfying one of three criteria: Guidancec navigable waters and wetlands that abutted (1) An unbroken surface or shallow subsurface connection to jurisdictional waters (which relatively permanent tributaries (described as may be intermittent); those that flow year-round or have continuous flow at least seasonally) of such waters were (2) Physical separation from jurisdictional waters by man-made dikes or barriers, natural categorically WOTUS river berms, beach dunes, or similar features; or • (3) Proximity to a jurisdictional water that is reasonably close and supports a science-based Wetlands adjacent to tributaries that are not inference of ecological interconnection. relatively permanent and wetlands adjacent to but not directly abutting a relatively permanent tributary were subject to case-by-case significant nexus analysis to determine jurisdiction CRS-17 link to page 22 link to page 22 Description of the Adjacent Wetlands WOTUS Definition of Adjacent Source Category 2015 Clean Water • Broadened the category to adjacent waters, • Defined adjacent to mean “bordering, contiguous, or neighboring” a traditional Ruled including wetlands, ponds, lakes, oxbows, navigable water, interstate water including an interstate wetland, jurisdictional impoundments, and similar waters rather than impoundment, or a jurisdictional tributary. just adjacent wetlands • Included “waters separated by constructed dikes or barriers, natural river berms, • Included waters adjacent to traditional navigable beach dunes, and the like.” waters, interstate waters including interstate • Specified that for the purposes of adjacency, an open water such as a pond or lake wetlands, jurisdictional impoundments, and includes any wetlands within or abutting its ordinary high water mark. jurisdictional tributaries • Specified that adjacency was not limited to waters located laterally to a traditional navigable water, interstate water including an interstate wetland, jurisdictional impoundment, or a jurisdictional tributary. Instead, adjacent waters were to also include all waters that connect segments of one of the aforementioned waters or were located at the head of one of these waters and are bordering, contiguous, or neighboring. • Newly defined neighboring, which set new numeric standards for determining adjacency (i.e., al waters located within 100 feet of the ordinary high water mark of a traditional navigable water, interstate water including an interstate wetland, jurisdictional impoundment, or a jurisdictional tributary; or within the 100-year floodplain of one of the aforementioned waters and not more than 1,500 feet from the ordinary high water mark of such water). 2020 Navigable Adjacent wetlands Defined adjacent wetlands to mean wetlands that: Waters Protection (1) abutted a territorial sea or traditional navigable water, tributary, or a lake, pond, or Rulee impoundment of a jurisdictional water; (2) were inundated by flooding from one of the aforementioned waters in a typical year; (3) were physically separated from one of the aforementioned waters only by a natural berm, bank, dune, or similar natural feature; or (4) were physically separated from one of the aforementioned waters only by an artificial dike, barrier, or similar artificial structure so long as that structure allowed for a direct hydrological surface connection to the water in a typical year Specified that an adjacent wetland is jurisdictional when a road or similar artificial structure divides the wetland so long as the structure allows for a direct hydrologic surface connection through or over that structure in a typical year CRS-18 link to page 22 link to page 22 Description of the Adjacent Wetlands WOTUS Definition of Adjacent Source Category 2023 WOTUS Rulef Includes wetlands adjacent to: • Bordering, contiguous, or neighboring (1) traditional navigable waters, interstate waters, or • Wetlands separated from other waters of the United States by man-made dikes or the territorial seas; barriers, natural river berms, beach dunes, and the like are “adjacent wetlands” (2) and with a continuous surface connection to jurisdictional impoundments or tributaries that are relatively permanent, standing, or continuously flowing bodies of water; or (3) jurisdictional impoundments or tributaries when the wetlands alone or in combination with similarly situated waters meet the significant nexus standard Sackett v. EPAg Adjacent wetlands that are part of (i.e., • “Only those wetlands that are as a practical matter indistinguishable from waters of indistinguishable from) waters of the United States the United States, such that it is difficult to determine where the water ends and the wetland begins. That occurs when wetlands have a continuous surface connection to bodies that are waters of the United States in their own right, so that there is no clear demarcation between waters and wetlands.” • Excludes wetlands that are neighboring to but separate from traditional navigable waters, such as those separated by a barrier. Source: CRS analysis of WOTUS regulations, guidance, and the Sackett v. EPA decision. Notes: a. Army Corps of Engineers, “Final Rule for Regulatory Programs of the Corps of Engineers,” 51 Federal Register 41206, Nov. 13, 1986 (1986 Corps Rule); EPA, “Clean Water Act Section 404 Program Definitions and Permit Exemptions; Section 404 State Program Regulations,” 53 Federal Register 20764, June 6, 1988 (1988 EPA Rule). b. The 1988 EPA Rule did not define adjacent, but the 1986 Corps Rule defined it as described here. c. Benjamin H. Grumbles, Assistant Administrator for Water, EPA, and John Paul Woodley Jr., Assistant Secretary of the Army (Civil Works), Department of the Army, Clean Water Act Jurisdiction Following the U.S. Supreme Court’s Decision in Rapanos v. United States & Carabell v. United States, memorandum, Dec. 2, 2008. d. Army Corps of Engineers and EPA, “Clean Water Rule: Definition of ‘Waters of the United States’; Final Rule,” 80 Federal Register 37054, June 29, 2015. e. Army Corps of Engineers and EPA, “The Navigable Waters Protection Rule: Definition of ‘Waters of the United States,’” 85 Federal Register 22250, Apr. 21, 2020. f. Revised Definition of “Waters of the United States,” 88 Federal Register 3004, Jan. 18, 2023. g. Sackett v. EPA, No. 21-454 (U.S. May 25, 2023). CRS-19 Waters of the United States (WOTUS): Frequently Asked Questions What Options Are Available to Congress Regarding the Definition of WOTUS? Considering the numerous court rulings, ongoing legal challenges, and successive Administrations’ efforts to define the scope of WOTUS, some stakeholders have urged Congress to more specifically define the term through amendments to the CWA. Others argue that the Corps and EPA, with their specific knowledge and expertise, are in the best position to determine the scope of the term. The Sackett v. EPA decision narrows the scope of WOTUS with regard to how the agencies may interpret the term moving forward but does not preclude Congress from amending the CWA to define the term with more clarity or specificity. The scope of WOTUS has continued to be an issue of interest in the 118th Congress. On February 8, 2023, the House Transportation and Infrastructure Committee’s Subcommittee on Water Resources and Environment held a hearing regarding the 2023 WOTUS Rule.109 Other committees have held hearings where the topic of WOTUS has been discussed, including a hearing held by the House Committee on Agriculture.110 Members have introduced legislation related to WOTUS. Members in both chambers introduced joint resolutions of disapproval of the 2023 WOTUS Rule under the Congressional Review Act (CRA). In addition, some Members have introduced legislation that would enact the Navigable Waters Protection Rule’s definition of WOTUS into law, reinstate the Navigable Waters Protection Rule, or amend the CWA to add a narrower definition of navigable waters. Another bill would establish an agricultural advisory committee to inform Congress of the impacts of WOTUS regulations on the agricultural sector. • H.J.Res. 27 and S.J.Res. 7 are joint resolutions providing for congressional disapproval of the 2023 WOTUS Rule under the CRA.111 They were sponsored or cosponsored by 170 Members of the House of Representatives and 49 Senators. In March 2023, both the House and the Senate passed the joint resolution of disapproval for the 2023 WOTUS Rule, which President Biden subsequently vetoed.112 The House held a vote to override the veto, which failed to meet the two-thirds majority needed to pass. • H.R. 1556, the Define WOTUS Act, and S. 1022, the Define WOTUS Act of 2023, are identical bills that would amend the CWA to change the definition of navigable waters. The language, as introduced, would narrow the scope of waters subject to CWA jurisdiction in comparison to any of the WOTUS regulatory 109 U.S. Congress, House Committee on Transportation and Infrastructure, Subcommittee on Water U.S. Congress, House Committee on Transportation and Infrastructure, Subcommittee on Water
Resources and Resources and Environment, Hearing on Stakeholder Perspectives on Impacts of the Biden Administration’s Waters of the United States (WOTUS) Rule, 118th Cong., 1st sess., Feb. 8, 2023. 110 U.S. Congress, House Committee on Agriculture, For the Purpose of Receiving Testimony from The Honorable Michael Regan, Administrator, U.S.~~Environment, The Administration’s Priorities and Policy Initiatives Under the Clean Water Act, 116th~~
~~Cong., 1st sess., September 18, 2019, H.Hrg. 116-31. U.S. Congress, Senate Committee on Environment and Public~~
~~Works,~~ ~~Hearing on the Nomination of Andrew Wheeler to be Administrator of the~~ Environmental Protection Agency,
~~116th Cong., 1st sess., January 16, 2019, S.Hrg. 116-9. U.S. Congress, Senate Committee on Environment and Public~~
~~Works, A Review of Waters of the U.S. Regulations: Their Impact on States and the American People, 116th Cong., 1st~~
~~sess., June 12, 2019, S.Hrg. 116-45. U.S. Congress, Senate Committee on Environment and Public Works,~~ ~~Oversight of~~
~~the Environmental Protection Agency, 116th Cong., 2nd sess., May 20, 2020, S.Hrg. 116-391. U.S. Congress, Senate~~
~~Committee on Environment and Public Works,~~ ~~Stakeholder Reactions: The Navigable Waters Protection Rule under~~
~~the Clean Water Act, 116th Cong., 2nd sess., September 16, 2020.~~
~~Congressional Research Service~~
~~R47408 · VERSION 3 · UPDATED~~
14, 118th Cong., 1st sess., Apr. 19, 2023. 111 The CRA allows Congress to overturn certain agency actions in the form of a joint resolution of disapproval.111 Under the CRA, if both houses pass a joint resolution for disapproval, it is sent to the President for signature or veto. If the President vetoes a resolution, Congress can vote to override the veto with a two-thirds majority in both chambers. If a joint resolution of disapproval is submitted within the CRA-specified deadline, passed by Congress, and signed by the President (or if Congress votes to override a presidential veto), the disapproved rule “shall not take effect (or continue)” and would be deemed not to have had any effect at any time. Furthermore, if a joint resolution of disapproval is enacted, the CRA provides that a rule may not be issued in “substantially the same form” as the disapproved rule unless it is specifically authorized by a subsequent law. 112 See, Actions. Congressional Research Service 20 Waters of the United States (WOTUS): Frequently Asked Questions • regimes (pre-2015, Clean Water Rule, Navigable Waters Protection Rule, and 2023 WOTUS Rule). It would also amend the CWA to make changes to the Corps process for making jurisdictional determinations. • S. 782, the FREE American Energy Act, would enact the Navigable Waters Protection Rule into law. • S. 879, the Energy Freedom Act, would reinstate the Navigable Waters Protection Rule and provide that each of its provisions apply until the effective date of a subsequent final rule. It would also prohibit the Corps and EPA from issuing a new rule to redefine WOTUS for 15 years from the date of enactment. • S. 1023, the Farmer-Informed WOTUS Act of 2023, would establish an advisory committee representative of the United States farming and ranching sectors to inform Congress of the impact of WOTUS regulations on U.S. agriculture. • S. 1449, the RESTART Act, would amend the CWA to change the definition of navigable waters. The language, as introduced, closely aligns with the definition published in the Navigable Waters Protection Rule. Moving forward, Congress may oversee the Biden Administration’s implementation of the Supreme Court’s ruling in Sackett v. EPA or may consider proposing legislation to either provide a definition of WOTUS or provide more specific instruction to the agencies and regulated parties as to the interpretation of the CWA. The Supreme Court’s increasing insistence on clear congressional intent to delegate regulatory authority, and its decreasing reliance on or reference to more deferential modes of judicial review, suggest that any regulatory actions taken pursuant to such legislation would be subject to close judicial scrutiny. Author Information Kate R. Bowers Laura Gatz Legislative Attorney Specialist in Environmental Policy Disclaimer This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan shared staff to congressional committees and Members of Congress. It operates solely at the behest of and 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 connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not subject to copyright protection in the United States. Any CRS Report may be reproduced and distributed in its entirety without permission from CRS. However, as a CRS Report may include copyrighted images or material from a third party, you may need to obtain the permission of the copyright holder if you wish to copy or otherwise use copyrighted material. Congressional Research Service R47408 · VERSION 5 · UPDATED 21