Supreme Court Narrows Federal Jurisdiction Under Clean Water Act

Legal Sidebari

Supreme Court Narrows Federal Jurisdiction

Under Clean Water Act

June 21, 2023

On May 25, 2023, the Supreme Court decided Sackett v. EPA, a case with significant implications for the

scope of federal jurisdiction under the Clean Water Act (CWA). While the Court unanimously agreed that

the lower court applied the wrong standard for determining when wetlands are considered “waters of the

United States” (WOTUS) based on their adjacency to other jurisdictional waters, it split 5-4 on the

appropriate test.

The majority formally adopted the approach taken by a four-Justice plurality in the 2006 case Rapanos v.

United States. Under the majority’s test, “waters” are limited to relatively permanent bodies of water

connected to traditional navigable waters and to wetlands that are “waters of the United States” in their

own right by virtue of a continuous surface connection to other jurisdictional waters so that there is no

clear demarcation between the bodies. Wetlands that are neighboring covered waters but are separated by

natural or artificial barriers are excluded.

The CWA prohibits discharging certain pollutants into navigable waters, defined as “the waters of the

United States, including the territorial seas” without a permit, but the statute does not define WOTUS.

The definition of WOTUS is important because it determines which waters are subject to federal

government regulations and protections, including CWA permitting programs. In January 2023, the U.S.

Army Corps of Engineers (Corps) and the U.S. Environmental Protection Agency (EPA)—the two

agencies tasked with implementing the CWA—issued a final rule redefining WOTUS. (See this report for

an in-depth discussion of the rule and the previous regulations promulgated to define the term.) The

Court’s ruling in Sackett construes the reach of the CWA more narrowly than the new or previous

regulatory interpretations or the approach adopted by the courts of appeals since Rapanos. While the

Sackett decision does not directly address the merits of the new rule, its rejection of several elements

included in the rule casts doubt on the current regulatory framework. It also evinces the Court’s

decreasing reliance on deferential modes of statutory construction as well as its increasing insistence on

clear congressional authorization for agency action.

Prior Supreme Court Rulings Regarding WOTUS

The Supreme Court has considered the scope of WOTUS in prior cases. (See this report for an in-depth

discussion of those cases.) Most recently, in 2006, the Supreme Court decided Rapanos v. United States, a

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pair of consolidated cases that concerned the extent of CWA jurisdiction over wetlands near ditches or

man-made drains that emptied into traditional navigable waters. Some had hoped that Rapanos would

provide clarity on jurisdictional questions that lingered after earlier decisions. Instead, the Court issued a

fractured 4-1-4 decision with two different standards and no majority opinion providing a rationale

indicating how to determine whether a particular waterbody is a water of the United States.

Writing for a four-Justice plurality, Justice Scalia articulated a bright-line rule holding that WOTUS

includes only “relatively permanent, standing or continuously flowing bodies of water” (such as streams,

rivers, or lakes) and wetlands that have a “continuous surface connection” to other waters subject to the

CWA. 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 nexus” to traditionally navigable

waters. Justice Kennedy further wrote that a significant nexus exists when the wetland, either alone or in

connection with similarly situated properties, significantly impacts the chemical, physical, and biological

integrity of a traditionally navigable water.

Following Rapanos, lower courts considered which Justice’s opinion should apply. Every court of appeals

to consider the two standards has held either that Justice Kennedy’s significant nexus standard is

controlling or that jurisdiction may be established under either standard. Some courts declined to identify

which opinion is controlling, either because the parties stipulated that the significant nexus standard

applied or because both tests had been met. The Ninth Circuit held in 2007 that Justice Kennedy’s

concurrence “is the narrowest ground to which a majority of the Justices would assent if forced to choose

in almost all cases” and therefore provided the controlling standard for cases within its circuit.

Regulations Defining WOTUS

The Corps and EPA have also defined WOTUS through successive regulations. For much of the past

several decades, regulations promulgated by the Corps and EPA in 1986 and 1988, respectively, have

been in effect. The agencies supplemented these regulations with interpretive guidance in 2003 and 2008

in response to Supreme Court rulings.

In 2015, the Corps and EPA issued the Clean Water Rule, which redefined WOTUS in the agencies’

regulations. The Trump Administration rescinded the Clean Water Rule in 2019, temporarily reverted to

the pre-2015 framework, and in 2020 codified a new definition in the Navigable Waters Protection Rule.

In August 2021, a federal district court vacated the Navigable Waters Protection Rule, prompting the

agencies to return again to the pre-2015 framework.

Most recently, on January 18, 2023, the Corps and EPA published a new rule (the 2023 WOTUS Rule)

revising the definition of WOTUS. Overall, 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. Of

particular relevance in the context of Sackett, the 2023 WOTUS Rule provides that certain wetlands are

jurisdictional based on their adjacency to other covered waters and, as in previous regulations, defines

adjacent as “bordering, contiguous, or neighboring.” Specifically, the rule includes wetlands that are

adjacent to a traditional navigable water, the territorial seas, or an interstate water, as well as and wetlands

that are adjacent to jurisdictional impoundments or tributaries and meet either the relatively permanent or

significant nexus standard.

Sackett v. EPA: Litigation History

The petitioners, Chantell and Michael Sackett, own a parcel of land in Idaho, near Priest Lake and across

the road from a wetlands complex that drains into an unnamed tributary of a creek that in turn feeds into

the lake. In 2007, after they began backfilling the property with sand and gravel, EPA issued a compliance

order directing them to restore the site. In 2008, the Corps issued a jurisdictional determination

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concluding that the property contained wetlands subject to regulation under the CWA, after which EPA

issued an amended compliance order that extended the compliance deadlines. The Sacketts sued EPA,

arguing that the compliance order was arbitrary and capricious because its underlying jurisdictional basis

was flawed. The district court granted summary judgment in favor of EPA, ruling that the Sacketts’

property contained jurisdictional wetlands.

The Ninth Circuit affirmed the district court’s grant of summary judgment in EPA’s favor. On the merits,

the court held that it was bound by its precedent to apply as the controlling opinion Justice Kennedy’s

concurrence in Rapanos. Applying Justice Kennedy’s significant nexus test, and looking to the regulations

that were in effect when EPA issued the amended compliance order, the court held that the record “plainly

supports” EPA’s conclusion that the wetlands on the Sacketts’ property were adjacent to a jurisdictional

tributary. The court also upheld EPA’s conclusion that those wetlands, together with the similarly situated

wetlands complex across the road, had a significant nexus to Priest Lake, a traditional navigable water.

The court thus concluded that EPA reasonably determined that the Sacketts’ property was subject to

federal jurisdiction under the CWA and the relevant regulations.

The Supreme Court’s Decision

The Supreme Court granted review to address “whether the Ninth Circuit set forth the proper test for

determining whether wetlands are ‘waters of the United States’ under the Clean Water Act.” On review,

the 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.

Justice Alito wrote the majority opinion and was joined by Chief Justice Roberts and Justices Thomas,

Gorsuch, and Barrett.

With respect to what constitutes “waters,” the majority reaffirmed the Rapanos plurality’s interpretation,

holding that “the CWA’s use of ‘waters’ encompasses only those 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.” The majority acknowledged that the Court’s prior

jurisprudence interpreted CWA jurisdiction to extend beyond traditional navigable waters but cautioned

that those earlier cases “refused to read ‘navigable’ out of the statute, holding that it at least shows that

Congress was focused on its traditional jurisdiction over waters that were or had been navigable in fact or

which could reasonably be so made.” The majority reasoned that this interpretation was consistent with

definitions of waters elsewhere in the CWA and in other statutes.

The majority acknowledged that some but not all wetlands are covered under the CWA and held that

jurisdictional wetlands “must be indistinguishably part of a body of water that itself constitutes ‘waters’

under the CWA.” Quoting the Rapanos plurality, the majority held 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.”

The majority reasoned that its interpretation harmonized the statutory term waters of the United States

with Section 404(g)(1) of the CWA, which was added in 1977 and authorizes states to apply to EPA for

approval to administer permits for certain kinds of discharges into any WOTUS except for certain

traditional navigable waters, “including wetlands adjacent thereto.” The majority explained that because

the adjacent wetlands in Section 404(g)(1) “are ‘includ[ed]’ within ‘waters of the United States,’” the

term navigable waters could not include WOTUS and adjacent wetlands, but only those adjacent

wetlands that qualify as WOTUS “in their own right.” As a result, the majority concluded that wetlands

“that are separate from traditional navigable waters cannot be considered part of those waters, even if they

are located nearby.”

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In addition to reaffirming the Rapanos plurality’s standard, the majority also rejected the significant nexus

test. The majority stated 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 cautioned that an overly broad interpretation of the CWA’s reach would impinge on the regulation of

land and water use, an area at the core of traditional state authority. The majority also wrote that EPA’s

interpretation “gives rise to serious vagueness concerns in light of the CWA’s criminal penalties.” In

particular, the majority emphasized that the boundary between a significant nexus and an insignificant one

was “far from clear,” that “similarly situated” waters was also a vague concept, and that application of the

significant nexus test required consideration of “a variety of open-ended factors that evolve as scientific

understandings change.” According to the majority, the significant nexus test amounted to a

“freewheeling inquiry” that “provides little notice to landowners of their obligations under the CWA.”

The majority also rejected EPA’s interpretation of WOTUS as including wetlands that are “neighboring”

to covered waters but separated by dry land. In particular, the majority disagreed with EPA’s argument

that the reference to adjacent wetlands in Section 404(g)(1) indicates that Congress implicitly ratified the

Corps’ regulatory definition of adjacent wetlands that was in place when Congress added that section of

the CWA in 1977. Contrary to EPA’s argument, the majority found that the definition of adjacent wetlands

was “[f]ar from [] well settled” as of the 1977 CWA amendments. The majority also disputed EPA’s

policy arguments regarding the environmental consequences of a narrower definition, noting that “the

CWA does not define the EPA’s jurisdiction based on ecological importance.”

The case also generated three concurring opinions. Justice Thomas joined the judgment in full and wrote

a separate concurring opinion, joined by Justice Gorsuch, to discuss the historical meaning of the terms

navigable and of the United States in the phrases navigable waters and waters of the United States.

Justice Thomas wrote that, prior to the enactment of the CWA, navigable waters were generally

understood to be those waters that were or could be used for interstate or foreign commerce and that

wetlands were historically excluded from the term. Justice Thomas further wrote that “[i]t would be

strange indeed” if, in enacting the CWA, “Congress sought to effect a fundamental transformation of

federal jurisdiction over water through phrases that had been in use to describe the traditional scope of

that jurisdiction for well over a century and that carried a well-understood meaning.” Applying this

reasoning, Justice Thomas concluded that the wetlands on the Sacketts’ property were not jurisdictional

because they lack a surface connection with a traditional navigable water; the nonnavigable tributary

across the street from the Sacketts’ property is not, has never been, and cannot reasonably be made a

highway of interstate or foreign commerce; Priest Lake is purely intrastate and has not been shown to be a

highway of interstate or foreign commerce; and EPA did not establish that the Sacketts’ actions would

obstruct or otherwise impede navigable capacity or the suitability of a water for interstate commerce.

Consistent with his long-standing views, Justice Thomas criticized federal environmental law’s

dependence on an “expansive interpretation” of the Commerce Clause, which deviates from the original

meaning of the Constitution. Justice Thomas characterized EPA’s interpretation as “a federal police

power, exercised in the most aggressive possible way,” and argued that it “renders the use of the term

‘navigable’ a nullity and involves an unprecedented and extravagant reading of the well-understood term

of art ‘the waters of the United States.’”

Justice Kavanaugh, joined by Justices Kagan, Sotomayor, and Jackson, wrote an opinion concurring in

the judgment. Although he agreed with the majority’s decision not to adopt the significant nexus test and

its conclusion that the wetlands on the Sacketts’ property are not covered by the CWA, Justice Kavanaugh

disagreed with the holding that only wetlands with a continuous surface connection are jurisdictional.

Instead, Justice Kavanaugh argued that wetlands are jurisdictional if they are bordering, contiguous, or

neighboring to covered waters, even if they are separated from those waters by a natural or artificial

barrier. Justice Kavanaugh criticized the majority’s ruling as “depart[ing] from the statutory text, from 45

years of consistent agency practice, and from this Court’s precedents.”

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Justice Kavanaugh criticized the majority for narrowing the test to cover only “adjoining” wetlands—

those contiguous to or bordering a covered water—as opposed to “adjacent” wetlands, which he defined

as including both wetlands contiguous to or bordering a covered water and wetlands separated from a

covered water only by a man-made dike or barrier, natural river berm, beach dune, or the like. According

to Justice Kavanaugh, adjacent and adjoining are commonly understood to have distinct meanings, and

Congress’s use of the broader term adjacent in the 1977 CWA amendments unambiguously means that the

statute does not require wetlands to adjoin (or touch) covered waters.

Addressing the environmental impacts of the majority’s decision, Justice Kavanaugh warned that the

majority’s narrowing of coverage to adjoining wetlands would exclude “long-regulated and longaccepted-to-be-regulable wetlands” and would have significant repercussions for water quality and flood

control throughout the United States, such as by excluding wetlands separated by flood control levees

from the Mississippi River and wetlands adjacent to but not adjoining Chesapeake Bay and its covered

tributaries. He also identified several areas in which the majority’s decision would generate regulatory

uncertainty.

Justice Kagan wrote a concurring opinion in which Justices Sotomayor and Jackson joined. While she

expressed agreement with Justice Kavanaugh’s interpretation of adjacent consistent with its ordinary

meaning and his emphasis on the environmental function of wetlands, including those that are separated

from a covered water by natural or artificial barriers, she wrote separately to criticize the majority’s

reliance on what she described as a “judicially manufactured clear-statement rule.”

Justice Kagan argued that there was no ambiguity or vagueness around the meaning of adjacent in the

text of the CWA. Citing her dissent last term in West Virginia v. EPA, she asserted that it was therefore

inappropriate for the majority to rely on a “judicially manufactured clear-statement rule” not to deal with

statutory vagueness or ambiguity but instead to correct the perceived overbreadth of the CWA. Justice

Kagan argued that this approach amounted to “a thumb on the scale for property owners—no matter that

the [CWA] ... is all about stopping property owners from polluting.”

Implications of the Court’s Decision

The Court’s ruling narrows the scope of jurisdiction under the CWA as compared to both its longstanding

regulatory implementation and the interpretation adopted by lower courts post-Rapanos. While the extent

of the change will depend on how the Corps and EPA implement various aspects of the decision, the

Sackett 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. Additionally, while the majority recognized that “temporary

interruptions in surface connection” such as from low tides or dry spells would not defeat jurisdiction, it

is not clear how temporary such an interruption must be in order to preserve a wetland’s jurisdictional

status.

Additionally, with respect to the bodies of water that are considered “waters” under the CWA, the

majority’s ruling covers “only those relatively permanent, standing or continuously flowing bodies of

water forming geographical features that are described in ordinary parlance as streams, oceans, rivers, and

lakes.” The majority opinion does not explicitly address ephemeral waters, which flow only in response to

precipitation, or intermittent waters, which flow continuously during certain times of year (such as when

snowpack melts). At a minimum, however, the majority’s interpretation would appear to exclude

ephemeral waters. This narrows the scope of waters as compared to the 2023 WOTUS Rule (but not the

2020 Navigable Waters Protection Rule).

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The Future of Federal and State Regulation

The Court’s decision in Sackett will have significant impacts on federal and state water regulation, but the

full extent of those impacts is not yet clear. 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” and that they “continue to review the decision to determine next steps.” Because the agencies

have consistently extended jurisdictional coverage to more wetlands than are covered under Sackett, there

is no current or previous regulatory framework that they could apply that would comport with the Sackett

majority’s holding. It remains to be seen whether the Corps and EPA will seek to amend their current

regulations, supplement the regulations with guidance, or issue new regulations.

Although the Sackett majority was decisive in its articulation of a jurisdictional test, the majority left

unanswered numerous questions about the parameters of the test. Justice Kavanaugh’s concurring opinion

identified some issues that may arise in the future, including how to determine whether a wetland is

“indistinguishable” from a covered water; how the test applies to wetlands with temporary interruptions in

surface connection due to seasonal variations or to wetlands in areas where storms, floods, and erosion

frequently shift or breach natural barriers; and whether ditches, swales, pipes, or culverts can establish a

continuous surface connection. These questions could be addressed in future regulations (and disputed in

future litigation), though the majority’s ruling suggests that the Court will not take a deferential view

toward agency interpretations of those issues.

Neither the 2023 WOTUS 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 2023 WOTUS Rule has been challenged in five lawsuits across three federal district courts. Prior to

the Supreme Court’s decision in Sackett, two of those courts—the U.S. District Court for the Southern

District of Texas and the U.S. District Court for the District of North Dakota—issued preliminary

injunctions barring implementation of the 2023 WOTUS Rule in the states that are participating in the

lawsuits before those courts. The U.S. District Court for the Eastern District of Kentucky denied the

plaintiffs’ motions for preliminary injunction and dismissed the case, but after the plaintiffs appealed that

decision, the U.S. Court of Appeals for the Sixth Circuit issued an injunction pending appeal that bars

implementation of the 2023 WOTUS Rule in Kentucky and for the plaintiff organizations and their

members. A total of 27 states and six industry associations and their members are covered by the

preliminary injunctions and injunction pending appeal. The Corps and EPA have stated that they will

interpret WOTUS “consistent with the pre-2015 regulatory regime” as to those states and plaintiffs. For

now, the 2023 WOTUS Rule remains in effect elsewhere. Further proceedings in the 2023 WOTUS Rule

litigation may affect the status of the rule in individual states or nationwide.

In the meantime, the Court’s decision in Sackett could delay CWA permitting and other actions as the

Corps and EPA determine how to implement the decision. In particular, the Corps may delay issuing

approved jurisdictional determinations (AJD), which are used to identify whether a particular parcel of

land contains WOTUS and which may be used in the CWA permitting process. After the Supreme Court

decided Rapanos, the Corps urged its district offices to delay issuing AJDs for areas beyond the limits of

the traditional navigable waters, and EPA interim guidance directed agency employees not to represent an

agency position on the effect of the decision until the agencies issued final guidance interpreting WOTUS

in light of the Court’s decision. At least one Corps district office has placed the issuance of AJDs on hold

until further notice. It is not yet clear if the agencies will impose similar directives nationwide.

Finally, the 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 cover more waters

in their own regulations. While some states regulate waters within their borders beyond the scope of

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federal jurisdiction, some state laws bar environmental state agencies from promulgating regulations

beyond what is federally required. A narrowed definition of WOTUS at the federal level could thus result

in greater state-level divergence in the scope of covered waters.

Considerations for Congress

The scope of CWA jurisdiction has long been of interest to Congress. Some Members of Congress filed

amici curiae briefs with the Court in Sackett, expressing their views on the issues presented in that case: A

coalition of 199 Members and a group of three Representatives from the Congressional Western Caucus

filed briefs with the Court in support of the Sacketts, and a coalition of 167 current and former Members

filed a brief in support of EPA. Following the Court’s decision, some Members have issued statements

either supporting or criticizing the ruling.

The Sackett majority’s emphasis on clear statement rules is also indicative of a shift in how the Supreme

Court views the relationship between Congress and agencies’ regulatory authority. This is the second

consecutive term in which the Supreme Court has curtailed EPA’s regulatory authority by holding that

Congress was required to provide clear authorization to EPA and had failed to do so in the relevant

statutory text. In West Virginia v. EPA, the Court applied the major questions doctrine to hold that, because

regulation of greenhouse gas emissions from power plants presented a question of vast economic or

political significance and there was not clear evidence of congressional intent to task EPA with balancing

the nationwide energy mix, the Clean Air Act did not authorize EPA to issue emission guidelines that

were based in part on shifting electricity generation from higher-emitting sources to lower-emitting ones.

Similarly, in Sackett, the majority reasoned that because broadening the scope of WOTUS would “alter

the balance between federal and state power and the power of the Government over private property,” the

Court would require “exceedingly clear language” from Congress in support of EPA’s interpretation.

Following Sackett, Congress could consider proposing legislation to 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

Legislative Attorney

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