Sackett v. EPA

(Slip Opinion) OCTOBER TERM, 2022 1

Syllabus

NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
being done in connection with this case, at the time the opinion is issued.
The syllabus constitutes no part of the opinion of the Court but has been
prepared by the Reporter of Decisions for the convenience of the reader.
See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.

SUPREME COURT OF THE UNITED STATES

Syllabus

SACKETT ET UX. v. ENVIRONMENTAL PROTECTION
AGENCY ET AL.

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
THE NINTH CIRCUIT

No. 21–454. Argued October 3, 2022—Decided May 25, 2023
Petitioners Michael and Chantell Sackett purchased property near
Priest Lake, Idaho, and began backfilling the lot with dirt to prepare
for building a home. The Environmental Protection Agency informed
the Sacketts that their property contained wetlands and that their
backfilling violated the Clean Water Act, which prohibits discharging
pollutants into “the waters of the United States.” 33 U. S. C. §1362(7).
The EPA ordered the Sacketts to restore the site, threatening penalties
of over $40,000 per day. The EPA classified the wetlands on the Sack-
etts’ lot as “waters of the United States” because they were near a ditch
that fed into a creek, which fed into Priest Lake, a navigable, intrastate
lake. The Sacketts sued, alleging that their property was not “waters
of the United States.” The District Court entered summary judgment
for the EPA. The Ninth Circuit affirmed, holding that the CWA covers
wetlands with an ecologically significant nexus to traditional naviga-
ble waters and that the Sacketts’ wetlands satisfy that standard.
Held: The CWA’s use of “waters” in §1362(7) refers only to “geo-
graphic[al] features that are described in ordinary parlance as
‘streams, oceans, rivers, and lakes’ ” and to adjacent wetlands that are
“indistinguishable” from those bodies of water due to a continuous sur-
face connection. Rapanos v. United States, 547 U. S. 715, 755, 742, 739
(plurality opinion). To assert jurisdiction over an adjacent wetland un-
der the CWA, a party must establish “first, that the adjacent [body of
water constitutes] . . . ‘water[s] of the United States’ (i.e., a relatively
permanent body of water connected to traditional interstate navigable
waters); and second, that the wetland has a continuous surface con-
nection with that water, making it difficult to determine where the
‘water’ ends and the ‘wetland’ begins.” Ibid. Pp. 6–28.
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(a) The uncertain meaning of “the waters of the United States” has
been a persistent problem, sparking decades of agency action and liti-
gation. Resolving the CWA’s applicability to wetlands requires a re-
view of the history surrounding the interpretation of that phrase.
Pp. 6–14.
(1) During the period relevant to this case, the two federal agen-
cies charged with enforcement of the CWA—the EPA and the Army
Corps of Engineers—similarly defined “the waters of the United
States” broadly to encompass “[a]ll . . . waters” that “could affect inter-
state or foreign commerce.” 40 CFR §230.3(s)(3). The agencies like-
wise gave an expansive interpretation of wetlands adjacent to those
waters, defining “adjacent” to mean “bordering, contiguous, or neigh-
boring.” §203.3(b). In United States v. Riverside Bayview Homes, Inc.,
474 U. S. 121, the Court confronted the Corps’ assertion of authority
under the CWA over wetlands that “actually abut[ted] on a navigable
waterway.” Id., at 135. Although concerned that the wetlands fell
outside “traditional notions of ‘waters,’ ” the Court deferred to the
Corps, reasoning that “the transition from water to solid ground is not
necessarily or even typically an abrupt one.” Id., 132–133. Following
Riverside Bayview, the agencies issued the “migratory bird rule,” ex-
tending CWA jurisdiction to any waters or wetlands that “are or would
be used as [a] habitat” by migratory birds or endangered species. 53
Fed. Reg. 20765. The Court rejected the rule after the Corps sought to
apply it to several isolated ponds located wholly within the State of
Illinois, holding that the CWA does not “exten[d] to ponds that are not
adjacent to open water.” Solid Waste Agency of Northern Cook Cty. v.
Army Corps of Engineers, 531 U. S. 159, 168 (SWANCC) (emphasis de-
leted). The agencies responded by instructing their field agents to de-
termine the scope of the CWA’s jurisdiction on a case-by-case basis.
Within a few years, the agencies had “interpreted their jurisdiction
over ‘the waters of the United States’ to cover 270-to-300 million acres”
of wetlands and “virtually any parcel of land containing a channel or
conduit . . . through which rainwater or drainage may occasionally or
intermittently flow.” Rapanos, 547 U. S., at 722 (plurality opinion).
Against that backdrop, the Court in Rapanos vacated a lower court
decision that had held that the CWA covered wetlands near ditches
and drains that emptied into navigable waters several miles away. As
to the rationale for vacating, however, no position in Rapanos com-
manded a majority of the Court. Four Justices concluded that the
CWA’s coverage was limited to certain relatively permanent bodies of
water connected to traditional interstate navigable waters and to wet-
lands that are “as a practical matter indistinguishable” from those wa-
ters. Id., at 755 (emphasis deleted). Justice Kennedy, concurring only
in the judgment, wrote that CWA jurisdiction over adjacent wetlands
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requires a “significant nexus” between the wetland and its adjacent
navigable waters, which exists when “the wetlands, either alone or in
combination with similarly situated lands in the region, significantly
affect the chemical, physical, and biological integrity” of those waters.
Id., at 779–780. Following Rapanos, field agents brought nearly all
waters and wetlands under the risk of CWA jurisdiction by engaging
in fact-intensive “significant-nexus” determinations that turned on a
lengthy list of hydrological and ecological factors.
Under the agencies’ current rule, traditional navigable waters, in-
terstate waters, and the territorial seas, as well as their tributaries
and adjacent wetlands, are waters of the United States. See 88 Fed.
Reg. 3143. So too are any “[i]ntrastate lakes and ponds, streams, or
wetlands” that either have a continuous surface connection to categor-
ically included waters or have a significant nexus to interstate or tra-
ditional navigable waters. Id., at 3006, 3143. Finding a significant
nexus continues to require consideration of a list of open-ended factors.
Ibid. Finally, the current rule returns to the agencies’ longstanding
definition of “adjacent.” Ibid. Pp. 6–12.
(2) Landowners who even negligently discharge pollutants into
navigable waters without a permit potentially face severe criminal and
civil penalties under the Act. As things currently stand, the agencies
maintain that the significant-nexus test is sufficient to establish juris-
diction over “adjacent” wetlands. By the EPA’s own admission, nearly
all waters and wetlands are potentially susceptible to regulation under
this test, putting a staggering array of landowners at risk of criminal
prosecution for such mundane activities as moving dirt. Pp. 12–14.
(b) Next, the Court considers the extent of the CWA’s geographical
reach. Pp. 14–22.
(1) To make sense of Congress’s choice to define “navigable wa-
ters” as “the waters of the United States,” the Court concludes that the
CWA’s use of “waters” encompasses “only those relatively permanent,
standing or continuously flowing bodies of water ‘forming geo-
graphic[al] features’ that are described in ordinary parlance as
‘streams, oceans, rivers, and lakes.’ ” Rapanos, 547 U. S., at 739 (plu-
rality opinion). This reading follows from the CWA’s deliberate use of
the plural “waters,” which refers to those bodies of water listed above,
and also helps to align the meaning of “the waters of the United States”
with the defined term “navigable waters.” More broadly, this reading
accords with how Congress has employed the term “waters” elsewhere
in the CWA—see, e.g., 33 U. S. C. §§1267(i)(2)(D), 1268(a)(3)(I)—and
in other laws—see, e.g., 16 U. S. C. §§745, 4701(a)(7). This Court has
understood CWA’s use of “waters” in the same way. See, e.g., Riverside
Bayview, 474 U. S., at 133; SWANCC, 531 U. S., at 168–169, 172.
The EPA’s insistence that “water” is “naturally read to encompass
4 SACKETT v. EPA

Syllabus

wetlands” because the “presence of water is ‘universally regarded as
the most basic feature of wetlands’ ” proves too much. Brief for Re-
spondents 19. It is also tough to square with SWANCC’s exclusion of
isolated ponds or Riverside Bayview’s extensive focus on the adjacency
of wetlands to covered waters. Finally, it is difficult to see how the
States’ “responsibilities and rights” in regulating water resources
would remain “primary” if the EPA had such broad jurisdiction.
§1251(b). Pp. 14–18.
(2) Statutory context shows that some wetlands nevertheless
qualify as “waters of the United States.” Specifically, §1344(g)(1),
which authorizes States to conduct certain permitting programs, spec-
ifies that discharges may be permitted into any waters of the United
States, except for traditional navigable waters, “including wetlands
adjacent thereto,” suggesting that at least some wetlands must qualify
as “waters of the United States.” But §1344(g)(1) cannot define what
wetlands the CWA regulates because it is not the operative provision
that defines the Act’s reach. Instead, the reference to adjacent wet-
lands in §1344(g)(1) must be harmonized with “the waters of the
United States,” which is the operative term that defines the CWA’s
reach. Because the “adjacent” wetlands in §1344(g)(1) are “includ[ed]”
within “waters of the United States,” these wetlands must qualify as
“waters of the United States” in their own right, i.e., be indistinguish-
ably part of a body of water that itself constitutes “waters” under the
CWA. To hold otherwise would require implausibly concluding that
Congress tucked an important expansion to the reach of the CWA into
convoluted language in a relatively obscure provision concerning state
permitting programs. Understanding the CWA to apply to wetlands
that are distinguishable from otherwise covered “waters of the United
States” would substantially broaden §1362(7) to define “navigable wa-
ters” as “waters of the United States and adjacent wetlands.” But
§1344(g)(1)’s use of the term “including” makes clear that it does not
purport to do any such thing. It merely reflects Congress’s assumption
that certain “adjacent” wetlands are part of the “waters of the United
States.”
To determine when a wetland is part of adjacent “waters of the
United States,” the Court agrees with the Rapanos plurality that the
use of “waters” in §1362(7) may be fairly read to include only wetlands
that are “indistinguishable from waters of the United States.” This
occurs only 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.” 547
U. S., at 742.
In sum, the CWA extends to only wetlands that are “as a practical
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Syllabus

matter indistinguishable from waters of the United States.” This re-
quires the party asserting jurisdiction to establish “first, that the ad-
jacent [body of water constitutes] . . . ‘water[s] of the United States’
(i.e., a relatively permanent body of water connected to traditional in-
terstate navigable waters); and second, that the wetland has a contin-
uous surface connection with that water, making it difficult to deter-
mine where the ‘water’ ends and the ‘wetland’ begins.” Rapanos, 547
U. S., at 755, 742. Pp. 18–22.
(c) The EPA asks the Court to defer to its most recent rule providing
that “adjacent wetlands are covered by the [CWA] if they ‘possess a
significant nexus to’ traditional navigable waters” and that wetlands
are “adjacent” when they are “neighboring” to covered waters. Brief
for Respondents 32, 20. For multiple reasons, the EPA’s position lacks
merit. Pp. 22–27.
(1) The EPA’s interpretation is inconsistent with the CWA’s text
and structure and clashes with “background principles of construction”
that apply to the interpretation of the relevant provisions. Bond v.
United States, 572 U. S. 844, 857. First, “exceedingly clear language”
is required if Congress wishes to alter the federal/state balance or the
Government’s power over private property. United States Forest Ser-
vice v. Cowpasture River Preservation Assn., 590 U. S. ___, ___. The
Court has thus required a clear statement from Congress when deter-
mining the scope of “the waters of the United States.” Second, the
EPA’s interpretation gives rise to serious vagueness concerns in light
of the CWA’s criminal penalties, thus implicating the due process re-
quirement that penal statutes be defined “ ‘with sufficient definiteness
that ordinary people can understand what conduct is prohibited.’ ”
McDonnell v. United States, 579 U. S. 550, 576. Where penal statutes
could sweep broadly enough to render criminal a host of what might
otherwise be considered ordinary activities, the Court has been wary
about going beyond what “Congress certainly intended the statute to
cover.” Skilling v. United States, 561 U. S. 358, 404. Under these two
principles, the judicial task when interpreting “the waters of the
United States” is to ascertain whether clear congressional authoriza-
tion exists for the EPA’s claimed power. Pp. 22–25.
(2) The EPA claims that Congress ratified the EPA’s regulatory
definition of “adjacent” when it amended the CWA to include the ref-
erence to “adjacent” wetlands in §1344(g)(1). This argument fails for
at least three reasons. First, the text of §§1362(7) and 1344(g) shows
that “adjacent” cannot include wetlands that are merely nearby cov-
ered waters. Second, EPA’s argument cannot be reconciled with this
Court’s repeated recognition that §1344(g)(1) “ ‘does not conclusively
determine the construction to be placed on . . . the relevant definition
of “navigable waters.” ’ ” SWANCC, 531 U. S., at 171. Third, the EPA
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falls short of establishing the sort of “overwhelming evidence of acqui-
escence” necessary to support its argument in the face of Congress’s
failure to amend §1362(7). Finally, the EPA’s various policy argu-
ments about the ecological consequences of a narrower definition of
“adjacent” are rejected. Pp. 25–27.
8 F. 4th 1075, reversed and remanded.

ALITO, J., delivered the opinion of the Court, in which ROBERTS, C. J.,
and THOMAS, GORSUCH, and BARRETT, JJ., joined. THOMAS, J., filed a
concurring opinion, in which GORSUCH, J., joined. KAGAN, J., filed an
opinion concurring in the judgment, in which SOTOMAYOR and JACKSON,
JJ., joined. KAVANAUGH, J., filed an opinion concurring in the judgment,
in which SOTOMAYOR, KAGAN, and JACKSON, JJ., joined.
 Cite as: 598 U. S. ____ (2023) 1

Opinion of the Court

NOTICE: This opinion is subject to formal revision before publication in the
United States Reports. Readers are requested to notify the Reporter of
Decisions, Supreme Court of the United States, Washington, D. C. 20543,
pio@supremecourt.gov, of any typographical or other formal errors.

SUPREME COURT OF THE UNITED STATES
_________________

No. 21–454
_________________

MICHAEL SACKETT, ET UX., PETITIONERS v.
ENVIRONMENTAL PROTECTION
AGENCY, ET AL.
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE NINTH CIRCUIT
[May 25, 2023]

JUSTICE ALITO delivered the opinion of the Court.
This case concerns a nagging question about the outer
reaches of the Clean Water Act (CWA), the principal federal
law regulating water pollution in the United States.1 By all
accounts, the Act has been a great success. Before its en-
actment in 1972, many of the Nation’s rivers, lakes, and
streams were severely polluted, and existing federal legis-
lation had proved to be inadequate. Today, many formerly
fetid bodies of water are safe for the use and enjoyment of
the people of this country.
There is, however, an unfortunate footnote to this success
story: the outer boundaries of the Act’s geographical reach
have been uncertain from the start. The Act applies to “the
waters of the United States,” but what does that phrase
mean? Does the term encompass any backyard that is
soggy enough for some minimum period of time? Does it
reach “mudflats, sandflats, wetlands, sloughs, prairie pot-
holes, wet meadows, [or] playa lakes?”2 How about ditches,
swimming pools, and puddles?
——————
1 86 Stat. 816, as amended, 33 U. S. C. §1251 et seq.
2 40 CFR §230.3(s)(3) (2008).
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Opinion of the Court

For more than a half century, the agencies responsible for
enforcing the Act have wrestled with the problem and
adopted varying interpretations. On three prior occasions,
this Court has tried to clarify the meaning of “the waters of
the United States.” But the problem persists. When we
last addressed the question 17 years ago, we were unable to
agree on an opinion of the Court.3 Today, we return to the
problem and attempt to identify with greater clarity what
the Act means by “the waters of the United States.”
I
A
For most of this Nation’s history, the regulation of water
pollution was left almost entirely to the States and their
subdivisions. The common law permitted aggrieved parties
to bring nuisance suits against polluters. But as industrial
production and population growth increased the quantity
and toxicity of pollution, States gradually shifted to enforce-
ment by regulatory agencies.4 Conversely, federal regula-
tion was largely limited to ensuring that “traditional navi-
gable waters”—that is, interstate waters that were either
navigable in fact and used in commerce or readily suscepti-
ble of being used in this way—remained free of impedi-
ments. See, e.g., Rivers and Harbors Act of 1899, 30 Stat.
1151; see also United States v. Appalachian Elec. Power Co.,
311 U. S. 377, 406–407 (1940); The Daniel Ball, 10 Wall.
557, 563 (1871).
Congress’s early efforts at directly regulating water pol-
lution were tepid. Although the Federal Water Pollution
Control Act of 1948 allowed federal officials to seek judicial
abatement of pollution in interstate waters, it imposed high
——————
3 See Rapanos v. United States, 547 U. S. 715 (2006). Neither party

contends that any opinion in Rapanos controls. We agree. See Nichols
v. United States, 511 U. S. 738, 745–746 (1994).
4 See N. Hines, Nor Any Drop To Drink: Public Regulation of Water

Quality, 52 Iowa L. Rev. 186, 196–207 (1966).
 Cite as: 598 U. S. ____ (2023) 3

Opinion of the Court

hurdles, such as requiring the consent of the State where
the pollution originated. See 62 Stat. 1156–1157. Despite
repeated amendments over the next two decades, few ac-
tions were brought under this framework.5
Congress eventually replaced this scheme in 1972 with
the CWA. See 86 Stat. 816. The Act prohibits “the dis-
charge of any pollutant” into “navigable waters.” 33
U. S. C. §§1311(a), 1362(12)(A). It broadly defines the term
“ ‘pollutant’ ” to include not only contaminants like “chemi-
cal wastes,” but also more mundane materials like “rock,
sand,” and “cellar dirt.” §1362(6).
The CWA is a potent weapon. It imposes what have been
described as “crushing” consequences “even for inadvertent
violations.” Army Corps of Engineers v. Hawkes Co., 578
U. S. 590, 602 (2016) (Kennedy, J., concurring). Property
owners who negligently discharge “pollutants” into covered
waters may face severe criminal penalties including impris-
onment. §1319(c). These penalties increase for knowing
violations. Ibid. On the civil side, the CWA imposes over
$60,000 in fines per day for each violation. See Note follow-
ing 28 U. S. C. §2461; 33 U. S. C. §1319(d); 88 Fed. Reg. 989
(2023) (to be codified in 40 CFR §19.4). And due to the Act’s
5-year statute of limitations, 28 U. S. C. §2462, and expan-
sive interpretations of the term “violation,” these civil pen-
alties can be nearly as crushing as their criminal counter-
parts, see, e.g., Borden Ranch Partnership v. United States
Army Corps of Engineers, 261 F. 3d 810, 813, 818 (CA9
2001) (upholding Agency decision to count each of 348
passes of a plow by a farmer through “jurisdictional” soil on
his farm as a separate violation), aff ’d by an equally divided
Court, 537 U. S. 99 (2002) (per curiam).
The Environmental Protection Agency (EPA) and the
——————
5 See Hearings on Activities of the Federal Water Pollution Control Ad-

ministration before the Subcommittee on Air and Water Pollution of the
Senate Committee on Public Works, 90th Cong., 1st Sess., 674 (1967)
(reporting only one abatement suit between 1948 and 1967).
4 SACKETT v. EPA

Opinion of the Court

Army Corps of Engineers (Corps) jointly enforce the CWA.
The EPA is tasked with policing violations after the fact,
either by issuing orders demanding compliance or by bring-
ing civil actions. §1319(a). The Act also authorizes private
plaintiffs to sue to enforce its requirements. §1365(a). On
the front end, both agencies are empowered to issue permits
exempting activity that would otherwise be unlawful under
the Act. Relevant here, the Corps controls permits for the
discharge of dredged or fill material into covered waters.
See §1344(a). The costs of obtaining such a permit are “sig-
nificant,” and both agencies have admitted that “the per-
mitting process can be arduous, expensive, and long.”
Hawkes Co., 578 U. S., at 594–595, 601. Success is also far
from guaranteed, as the Corps has asserted discretion to
grant or deny permits based on a long, nonexclusive list of
factors that ends with a catchall mandate to consider “in
general, the needs and welfare of the people.” 33 CFR
§320.4(a)(1) (2022).
Due to the CWA’s capacious definition of “pollutant,” its
low mens rea, and its severe penalties, regulated parties
have focused particular attention on the Act’s geographic
scope. While its predecessor encompassed “interstate or
navigable waters,” 33 U. S. C. §1160(a) (1970 ed.), the CWA
prohibits the discharge of pollutants into only “navigable
waters,” which it defines as “the waters of the United
States, including the territorial seas,” 33 U. S. C. §§1311(a),
1362(7), (12)(A) (2018 ed.). The meaning of this definition
is the persistent problem that we must address.
B
Michael and Chantell Sackett have spent well over a dec-
ade navigating the CWA, and their voyage has been bumpy
and costly. In 2004, they purchased a small lot near Priest
Lake, in Bonner County, Idaho. In preparation for building
a modest home, they began backfilling their property with
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Opinion of the Court

dirt and rocks. A few months later, the EPA sent the Sack-
etts a compliance order informing them that their backfill-
ing violated the CWA because their property contained pro-
tected wetlands. The EPA demanded that the Sacketts
immediately “ ‘undertake activities to restore the Site’ ” pur-
suant to a “ ‘Restoration Work Plan’ ” that it provided. Sack-
ett v. EPA, 566 U. S. 120, 125 (2012). The order threatened
the Sacketts with penalties of over $40,000 per day if they
did not comply.
At the time, the EPA interpreted “the waters of the
United States” to include “[a]ll . . . waters” that “could affect
interstate or foreign commerce,” as well as “[w]etlands ad-
jacent” to those waters. 40 CFR §§230.3(s)(3), (7) (2008).
“[A]djacent” was defined to mean not just “bordering” or
“contiguous,” but also “neighboring.” §230.3(b). Agency
guidance instructed officials to assert jurisdiction over wet-
lands “adjacent” to non-navigable tributaries when those
wetlands had “a significant nexus to a traditional navigable
water.”6 A “significant nexus” was said to exist when “ ‘wet-
lands, either alone or in combination with similarly situ-
ated lands in the region, significantly affect the chemical,
physical, and biological integrity’ ” of those waters. 2007
Guidance 8 (emphasis added). In looking for evidence of a
“significant nexus,” field agents were told to consider a wide
range of open-ended hydrological and ecological factors.
See id., at 7.
According to the EPA, the “wetlands” on the Sacketts’ lot
are “adjacent to” (in the sense that they are in the same
neighborhood as) what it described as an “unnamed tribu-
tary” on the other side of a 30-foot road. App. 33. That
tributary feeds into a non-navigable creek, which, in turn,
feeds into Priest Lake, an intrastate body of water that the

——————
6 EPA & Corps, Clean Water Act Jurisdiction Following the U. S. Su-

preme Court’s Decision in Rapanos v. United States & Carabell v. United
States 7–11 (2007) (2007 Guidance).
6 SACKETT v. EPA

Opinion of the Court

EPA designated as traditionally navigable. To establish a
significant nexus, the EPA lumped the Sacketts’ lot to-
gether with the Kalispell Bay Fen, a large nearby wetland
complex that the Agency regarded as “similarly situated.”
According to the EPA, these properties, taken together,
“significantly affect” the ecology of Priest Lake. Therefore,
the EPA concluded, the Sacketts had illegally dumped soil
and gravel onto “the waters of the United States.”
The Sacketts filed suit under the Administrative Proce-
dure Act, 5 U. S. C. §702 et seq., alleging that the EPA
lacked jurisdiction because any wetlands on their property
were not “waters of the United States.” The District Court
initially dismissed the suit, reasoning that the compliance
order was not a final agency action, but this Court ulti-
mately held that the Sacketts could bring their suit under
the APA. See Sackett, 566 U. S., at 131. After seven years
of additional proceedings on remand, the District Court en-
tered summary judgment for the EPA. 2019 WL 13026870
(D Idaho, Mar. 31, 2019). The Ninth Circuit affirmed, hold-
ing that the CWA covers adjacent wetlands with a signifi-
cant nexus to traditional navigable waters and that the
Sacketts’ lot satisfied that standard. 8 F. 4th 1075, 1091–
1093 (2021).
We granted certiorari to decide the proper test for deter-
mining whether wetlands are “waters of the United States.”
595 U. S. ___ (2022).
II
A
In defining the meaning of “the waters of the United
States,” we revisit what has been “a contentious and diffi-
cult task.” National Assn. of Mfrs. v. Department of De-
fense, 583 U. S. ___, ___ (2018) (slip op., at 1). The phrase
has sparked decades of agency action and litigation. In or-
der to resolve the CWA’s applicability to wetlands, we begin
by reviewing this history.
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Opinion of the Court

The EPA and the Corps initially promulgated different
interpretations of “the waters of the United States.” The
EPA defined its jurisdiction broadly to include, for example,
intrastate lakes used by interstate travelers. 38 Fed. Reg.
13529 (1973). Conversely, the Corps, consistent with its
historical authority to regulate obstructions to navigation,
asserted jurisdiction over only traditional navigable waters.
39 Fed. Reg. 12119 (1974). But the Corps’ narrow definition
did not last. It soon promulgated new, much broader defi-
nitions designed to reach the outer limits of Congress’s com-
merce power. See 42 Fed. Reg. 37144, and n. 2 (1977); 40
Fed. Reg. 31324–31325 (1975).
Eventually the EPA and Corps settled on materially iden-
tical definitions. See 45 Fed. Reg. 33424 (1980); 47 Fed.
Reg. 31810–31811 (1982). These broad definitions encom-
passed “[a]ll . . . waters” that “could affect interstate or for-
eign commerce.” 40 CFR §230.3(s)(3) (2008). So long as the
potential for an interstate effect was present, the regulation
extended the CWA to, for example, “intrastate lakes, rivers,
streams (including intermittent streams), mudflats, sand-
flats, wetlands, sloughs, prairie potholes, wet meadows,
playa lakes, or natural ponds.” Ibid. The agencies likewise
took an expansive view of the CWA’s coverage of wetlands
“adjacent” to covered waters. §230.3(s)(7). As noted, they
defined “adjacent” to mean “bordering, contiguous, or
neighboring” and clarified that “adjacent” wetlands include
those that are separated from covered waters “by man-
made dikes or barriers, natural river berms, beach dunes
and the like.” §230.3(b). They also specified that “wet-
lands” is a technical term encompassing “those areas that
are inundated or saturated by surface or ground water at a
frequency and duration sufficient to support, and that un-
der normal conditions do support, a prevalence of vegeta-
tion typically adapted for life in saturated soil conditions.”
§230.3(t). The Corps released what would become a 143-
page manual to guide officers when they determine whether
8 SACKETT v. EPA

Opinion of the Court

property meets this definition.7
This Court first construed the meaning of “the waters of
the United States” in United States v. Riverside Bayview
Homes, Inc., 474 U. S. 121 (1985). There, we were con-
fronted with the Corps’ assertion of authority under the
CWA over wetlands that “actually abut[ted] on a navigable
waterway.” Id., at 135. Although we expressed concern
that wetlands seemed to fall outside “traditional notions of
‘waters,’ ” we nonetheless deferred to the Corps, reasoning
that “the transition from water to solid ground is not neces-
sarily or even typically an abrupt one.” Id., at 132–133.
The agencies responded to Riverside Bayview by expand-
ing their interpretations even further. Most notably, they
issued the “migratory bird rule,” which extended jurisdic-
tion to any waters or wetlands that “are or would be used
as [a] habitat” by migratory birds or endangered species.
See 53 Fed. Reg. 20765 (1988); 51 Fed. Reg. 41217 (1986).
As the Corps would later admit, “nearly all waters were ju-
risdictional under the migratory bird rule.”8
In Solid Waste Agency of Northern Cook Cty. v. Army
Corps of Engineers, 531 U. S. 159 (2001) (SWANCC), this
Court rejected the migratory bird rule, which the Corps had
used to assert jurisdiction over several isolated ponds lo-
cated wholly within the State of Illinois. Disagreeing with
the Corps’ argument that ecological interests supported its
jurisdiction, we instead held that the CWA does not “ex-
ten[d] to ponds that are not adjacent to open water.” Id., at
168 (emphasis deleted).
Days after our decision, the agencies issued guidance that
——————
7 See Corps, Wetlands Delineation Manual (Tech. Rep. Y–87–1, 1987)

(Wetlands Delineation Manual); see also, e.g., Corps, Regional Supple-
ment to the Corps of Engineers Wetland Delineation Manual: Alaska Re-
gion (Version 2.0) (ERDC/EL Tr–07–24, 2007).
8 GAO, Waters and Wetlands: Corps of Engineers Needs To Evaluate

Its District Office Practices in Determining Jurisdiction 26 (GAO–04–
297, 2004) (GAO Report).
 Cite as: 598 U. S. ____ (2023) 9

Opinion of the Court

sought to minimize SWANCC’s impact. They took the view
that this Court’s holding was “strictly limited to waters that
are ‘nonnavigable, isolated, and intrastate’ ” and that “field
staff should continue to exercise CWA jurisdiction to the
full extent of their authority” for “any waters that fall out-
side of that category.”9 The agencies never defined exactly
what they regarded as the “full extent of their authority.”
They instead encouraged local field agents to make deci-
sions on a case-by-case basis.
What emerged was a system of “vague” rules that de-
pended on “locally developed practices.” GAO Report 26.
Deferring to the agencies’ localized decisions, lower courts
blessed an array of expansive interpretations of the CWA’s
reach. See, e.g., United States v. Deaton, 332 F. 3d 698, 702
(CA4 2003) (holding that a property owner violated the
CWA by piling soil near a ditch 32 miles from navigable wa-
ters). Within a few years, the agencies had “interpreted
their jurisdiction over ‘the waters of the United States’ to
cover 270-to-300 million acres” of wetlands and “virtually
any parcel of land containing a channel or conduit . . .
through which rainwater or drainage may occasionally or
intermittently flow.” Rapanos v. United States, 547 U. S.
715, 722 (2006) (plurality opinion).
It was against this backdrop that we granted review in
Rapanos v. United States. The lower court in the principal
case before us had held that the CWA covered wetlands
near ditches and drains that eventually emptied into navi-
gable waters at least 11 miles away, a theory that had sup-
ported the petitioner’s conviction in a related prosecution.
Id., at 720, 729. Although we vacated that decision, no po-
sition commanded a majority of the Court. Four Justices
concluded that the CWA’s coverage did not extend beyond
two categories: first, certain relatively permanent bodies of
——————
9 EPA & Corps, Memorandum, Supreme Court Ruling Concerning

CWA Jurisdiction Over Isolated Waters 3 (2001) (alteration omitted).
10 SACKETT v. EPA

Opinion of the Court

water connected to traditional interstate navigable waters
and, second, wetlands with such a close physical connection
to those waters that they were “as a practical matter indis-
tinguishable from waters of the United States.” Id., at 742,
755 (emphasis deleted). Four Justices would have deferred
to the Government’s determination that the wetlands at is-
sue were covered under the CWA. Id., at 788 (Stevens, J.,
dissenting). Finally, one Justice concluded that jurisdiction
under the CWA requires a “significant nexus” between wet-
lands and navigable waters and that such a nexus exists
where “the wetlands, either alone or in combination with
similarly situated lands in the region, significantly affect
the chemical, physical, and biological integrity” of those wa-
ters. Id., at 779–780 (Kennedy, J., concurring in judgment).
In the decade following Rapanos, the EPA and the Corps
issued guidance documents that “recognized larger grey ar-
eas and called for more fact-intensive individualized deter-
minations in those grey areas.”10 As discussed, they in-
structed agency officials to assert jurisdiction over
wetlands “adjacent” to non-navigable tributaries based on
fact-specific determinations regarding the presence of a sig-
nificant nexus. 2008 Guidance 8. The guidance further ad-
vised officials to make this determination by considering a
lengthy list of hydrological and ecological factors. Ibid.
Echoing what they had said about the migratory bird rule,
the agencies later admitted that “almost all waters and wet-
lands across the country theoretically could be subject to a
case-specific jurisdictional determination” under this guid-
ance. 80 Fed. Reg. 37056 (2015); see, e.g., Hawkes Co., 578
U. S., at 596 (explaining that the Corps found a significant
nexus between wetlands and a river “some 120 miles
——————
10 N. Parrillo, Federal Agency Guidance and the Power To Bind: An

Empirical Study of Agencies and Industries, 36 Yale J. on Reg. 165, 231
(2019); see 2007 Guidance 7–11; EPA & Corps, Clean Water Act Juris-
diction Following the U. S. Supreme Court’s Decision in Rapanos v.
United States & Carabell v. United States 8–12 (2008) (2008 Guidance).
 Cite as: 598 U. S. ____ (2023) 11

Opinion of the Court

away”).
More recently, the agencies have engaged in a flurry of
rulemaking defining “the waters of the United States.” In
a 2015 rule, they offered a muscular approach that would
subject “the vast majority of the nation’s water features” to
a case-by-case jurisdictional analysis.11 Although the rule
listed a few examples of “waters” that were excluded from
regulation like “[p]uddles” and “swimming pools,” it cate-
gorically covered other waters and wetlands, including any
within 1,500 feet of interstate or traditional navigable wa-
ters. 80 Fed. Reg. 37116–37117. And it subjected a wider
range of other waters, including any within 4,000 feet of in-
direct tributaries of interstate or traditional navigable wa-
ters, to a case-specific determination for significant nexus.
Ibid.
The agencies repealed this sweeping rule in 2019. 84
Fed. Reg. 56626. Shortly afterwards, they replaced it with
a narrower definition that limited jurisdiction to traditional
navigable waters and their tributaries, lakes, and “adja-
cent” wetlands. 85 Fed. Reg. 22340 (2020). They also nar-
rowed the definition of “[a]djacent,” limiting it to wetlands
that “[a]but” covered waters, are flooded by those waters, or
are separated from those waters by features like berms or
barriers. Ibid. This rule too did not last. After granting
the EPA’s voluntary motion to remand, a District Court va-
cated the rule. See Pascua Yaqui Tribe v. EPA, 557
F. Supp. 3d 949, 957 (D Ariz. 2021).
The agencies recently promulgated yet another rule at-
tempting to define waters of the United States. 88 Fed.
Reg. 3004 (2023) (to be codified in 40 CFR §120.2). Under
that broader rule, traditional navigable waters, interstate
waters, and the territorial seas, as well as their tributaries
and adjacent wetlands, are waters of the United States. 88
——————
11 EPA & Dept. of the Army, Economic Analysis of the EPA-Army

Clean Water Rule 11 (2015).
12 SACKETT v. EPA

Opinion of the Court

Fed. Reg. 3143. So are any “[i]ntrastate lakes and ponds,
streams, or wetlands” that either have a continuous surface
connection to categorically included waters or have a signif-
icant nexus to interstate or traditional navigable waters.
Id., at 3006, 3143. Like the post-Rapanos guidance, the
rule states that a significant nexus requires consideration
of a list of open-ended factors. 88 Fed. Reg. 3006, 3144. Fi-
nally, the rule returns to the broad pre-2020 definition of
“adjacent.” Ibid.; see supra, at 7. Acknowledging that
“[f ]ield work is often necessary to confirm the presence of a
wetland” under these definitions, the rule instructs local
agents to continue using the Corps’ Wetlands Delineation
Manual. 88 Fed. Reg. 3117.
B
With the benefit of a half century of practice under the
CWA, it is worth taking stock of where things stand. The
agencies maintain that the significant-nexus test has been
and remains sufficient to establish jurisdiction over “adja-
cent” wetlands. And by the EPA’s own admission, “almost
all waters and wetlands” are potentially susceptible to reg-
ulation under that test. 80 Fed. Reg. 37056. This puts
many property owners in a precarious position because it is
“often difficult to determine whether a particular piece of
property contains waters of the United States.” Hawkes
Co., 578 U. S., at 594; see 40 CFR §230.3(t) (2008). Even if
a property appears dry, application of the guidance in a
complicated manual ultimately decides whether it contains
wetlands. See 88 Fed. Reg. 3117; Wetlands Delineation
Manual 84–85 (describing “not . . . atypical” examples of
wetlands that periodically lack wetlands indicators); see
also Hawkes Co. v. United States Army Corps of Engineers,
782 F. 3d 994, 1003 (CA8 2015) (Kelly, J., concurring) (“This
is a unique aspect of the CWA; most laws do not require the
hiring of expert consultants to determine if they even apply
to you or your property”). And because the CWA can sweep
 Cite as: 598 U. S. ____ (2023) 13

Opinion of the Court

broadly enough to criminalize mundane activities like mov-
ing dirt, this unchecked definition of “the waters of the
United States” means that a staggering array of landown-
ers are at risk of criminal prosecution or onerous civil pen-
alties.
What are landowners to do if they want to build on their
property? The EPA recommends asking the Corps for a ju-
risdictional determination, which is a written decision on
whether a particular site contains covered waters. Tr. of
Oral Arg. 86; see Corps, Regulatory Guidance Letter No.
16–01, at 1 (2016) (RGL 16–01); 33 CFR §§320.1(a)(6),
331.2. But the Corps maintains that it has no obligation to
provide jurisdictional determinations, RGL 16–01, at 2, and
it has already begun announcing exceptions to the legal ef-
fect of some previous determinations, see 88 Fed. Reg. 3136.
Even if the Corps is willing to provide a jurisdictional de-
termination, a property owner may find it necessary to re-
tain an expensive expert consultant who is capable of put-
ting together a presentation that stands a chance of
persuading the Corps.12 And even then, a landowner’s
chances of success are low, as the EPA admits that the
Corps finds jurisdiction approximately 75% of the time. Tr.
of Oral Arg. 110.
If the landowner is among the vast majority who receive
adverse jurisdictional determinations, what then? It would
be foolish to go ahead and build since the jurisdictional de-
termination might form evidence of culpability in a prose-
cution or civil action. The jurisdictional determination
could be challenged in court, but only after the delay and
expense required to exhaust the administrative appeals
——————
12 See 88 Fed. Reg. 3134; Corps, Questions and Answers for Rapanos

and Carabell Decision 16 (2007); J. Finkle, Jurisdictional Determina-
tions: An Important Battlefield in the Clean Water Act Fight, 43 Ecology
L. Q. 301, 314–315 (2016); K. Gould, Drowning in Wetlands Jurisdic-
tional Determination Process: Implementation of Rapanos v. United
States, 30 U. Ark. Little Rock L. Rev. 413, 440 (2008).
14 SACKETT v. EPA

Opinion of the Court

process. See 33 CFR §331.7(d). And once in court, the land-
owner would face an uphill battle under the deferential
standards of review that the agencies enjoy. See 5 U. S. C.
§706. Another alternative would be simply to acquiesce and
seek a permit from the Corps. But that process can take
years and cost an exorbitant amount of money. Many land-
owners faced with this unappetizing menu of options would
simply choose to build nothing.
III
With this history in mind, we now consider the extent of
the CWA’s geographical reach.
A
We start, as we always do, with the text of the CWA. Bar-
tenwerfer v. Buckley, 598 U. S. 69, 74 (2023). As noted, the
Act applies to “navigable waters,” which had a well-estab-
lished meaning at the time of the CWA’s enactment. But
the CWA complicates matters by proceeding to define “nav-
igable waters” as “the waters of the United States,”
§1362(7), which was decidedly not a well-known term of art.
This frustrating drafting choice has led to decades of litiga-
tion, but we must try to make sense of the terms Congress
chose to adopt. And for the reasons explained below, we
conclude that the Rapanos plurality was correct: the CWA’s
use of “waters” encompasses “only those relatively perma-
nent, standing or continuously flowing bodies of water
‘forming geographic[al] features’ that are described in ordi-
nary parlance as ‘streams, oceans, rivers, and lakes.’ ” 547
U. S., at 739 (quoting Webster’s New International Diction-
ary 2882 (2d ed. 1954) (Webster’s Second); original altera-
tions omitted).
This reading follows from the CWA’s deliberate use of the
plural term “waters.” See 547 U. S., at 732–733. That term
typically refers to bodies of water like those listed above.
See, e.g., Webster’s Second 2882; Black’s Law Dictionary
 Cite as: 598 U. S. ____ (2023) 15

Opinion of the Court

1426 (5th ed. 1979) (“especially in the plural, [water] may
designate a body of water, such as a river, a lake, or an
ocean, or an aggregate of such bodies of water, as in the
phrases ‘foreign waters,’ ‘waters of the United States,’ and
the like” (emphasis added)); Random House Dictionary of
the English Language 2146 (2d ed. 1987) (Random House
Dictionary) (defining “waters” as “a. flowing water, or water
moving in waves: The river’s mighty waters. b. the sea or
seas bordering a particular country or continent or located
in a particular part of the world” (emphasis deleted)). This
meaning is hard to reconcile with classifying “ ‘ “lands,” wet
or otherwise, as “waters.” ’ ” Rapanos, 547 U. S., at 740 (plu-
rality opinion) (quoting Riverside Bayview, 474 U. S., at
132).
This reading also helps to align the meaning of “the wa-
ters of the United States” with the term it is defining: “nav-
igable waters.” See Bond v. United States, 572 U. S. 844,
861 (2014) (“In settling on a fair reading of a statute, it is
not unusual to consider the ordinary meaning of a defined
term, particularly when there is dissonance between that
ordinary meaning and the reach of the definition”). Alt-
hough we have acknowledged that the CWA extends to
more than traditional navigable waters, we have refused to
read “navigable” out of the statute, holding that it at least
shows that Congress was focused on “its traditional juris-
diction over waters that were or had been navigable in fact
or which could reasonably be so made.” SWANCC, 531
U. S., at 172; see also Appalachian Electric, 311 U. S., at
406–407; The Daniel Ball, 10 Wall., at 563. At a minimum,
then, the use of “navigable” signals that the definition prin-
cipally refers to bodies of navigable water like rivers, lakes,
and oceans. See Rapanos, 547 U. S., at 734 (plurality opin-
ion).
More broadly, this reading accords with how Congress
has employed the term “waters” elsewhere in the CWA and
16 SACKETT v. EPA

Opinion of the Court

in other laws. The CWA repeatedly uses “waters” in con-
texts that confirm the term refers to bodies of open water.
See 33 U. S. C. §1267(i)(2)(D) (“the waters of the Chesa-
peake Bay”); §1268(a)(3)(I) (“the open waters of each of the
Great Lakes”); §1324(d)(4)(B)(ii) (“lakes and other surface
waters”); §1330(g)(4)(C)(vii) (“estuarine waters”);
§1343(c)(1) (“the waters of the territorial seas, the contigu-
ous zone, and the oceans”); §§1346(a)(1), 1375a(a) (“coastal
recreation waters”); §1370 (state “boundary waters”). The
use of “waters” elsewhere in the U. S. Code likewise corre-
lates to rivers, lakes, and oceans.13
Statutory history points in the same direction. The
CWA’s predecessor statute covered “interstate or navigable
waters” and defined “interstate waters” as “all rivers, lakes,
and other waters that flow across or form a part of State
boundaries.” 33 U. S. C. §§1160(a), 1173(e) (1970 ed.) (em-
phasis added); see also Rivers and Harbors Act of 1899, 30
Stat. 1151 (codified, as amended, at 33 U. S. C. §403) (pro-
hibiting unauthorized obstructions “to the navigable capac-
ity of any of the waters of the United States”).
This Court has understood the CWA’s use of “waters” in
the same way. Even as Riverside Bayview grappled with
whether adjacent wetlands could fall within the CWA’s cov-
erage, it acknowledged that wetlands are not included in
“traditional notions of ‘waters.’ ” 474 U. S., at 133. It ex-
plained that the term conventionally refers to “hydro-
graphic features” like “rivers” and “streams.” Id., at 131.
SWANCC went even further, repeatedly describing the
“waters” covered by the Act as “open water” and suggesting
——————
13 See, e.g., 16 U. S. C. §745 (“the waters of the seacoast . . . the waters

of the lakes”); §4701(a)(7) (“waters of the Chesapeake Bay”); 33 U. S. C.
§4 (“the waters of the Mississippi River and its tributaries”); 43 U. S. C.
§390h–8(a) (“the waters of Lake Cheraw, Colorado . . . the waters of the
Arkansas River”); 46 U. S. C. §70051 (allowing the Coast Guard to take
control of particular vessels during an emergency in order to “prevent
damage or injury to any harbor or waters of the United States”).
 Cite as: 598 U. S. ____ (2023) 17

Opinion of the Court

that “the waters of the United States” principally refers to
traditional navigable waters. 531 U. S., at 168–169, 172.
That our CWA decisions operated under this assumption is
unsurprising. Ever since Gibbons v. Ogden, 9 Wheat. 1
(1824), this Court has used “waters of the United States” to
refer to similar bodies of water, almost always in relation to
ships. Id., at 218 (discussing a vessel’s “conduct in the wa-
ters of the United States”).14
The EPA argues that “waters” is “naturally read to en-
compass wetlands” because the “presence of water is ‘uni-
versally regarded as the most basic feature of wetlands.’ ”
Brief for Respondents 19. But that reading proves too
much. Consider puddles, which are also defined by the or-
dinary presence of water even though few would describe
them as “waters.” This argument is also tough to square
with SWANCC, which held that the Act does not cover iso-
lated ponds, see 531 U. S., at 171, or Riverside Bayview,
which would have had no need to focus so extensively on the
adjacency of wetlands to covered waters if the EPA’s read-
ing were correct, see 474 U. S., at 131–135, and n. 8. Fi-
nally, it is also instructive that the CWA expressly “pro-
tect[s] the primary responsibilities and rights of States to
prevent, reduce, and eliminate pollution” and “to plan the
development and use . . . of land and water resources.”
——————
14 See, e.g., United States v. Alvarez-Machain, 504 U. S. 655, 661, n. 7

(1992) (discussing a treaty “to allow British passenger ships to carry liq-
uor while in the waters of the United States”); Kent v. Dulles, 357 U. S.
116, 123 (1958) (discussing a prohibition on boarding “vessels of the en-
emy on waters of the United States”); New Jersey v. New York City, 290
U. S. 237, 240 (1933) (enjoining employees of New York City from dump-
ing garbage “into the ocean, or waters of the United States, off the coast
of New Jersey”); Cunard S. S. Co. v. Mellon, 262 U. S. 100, 127 (1923)
(holding that the National Prohibition Act did not apply to “merchant
ships when outside the waters of the United States”); Keck v. United
States, 172 U. S. 434, 444–445 (1899) (holding that concealing imported
goods on vessels “at the time of entering the waters of the United States,”
without more, did not constitute smuggling).
18 SACKETT v. EPA

Opinion of the Court

§1251(b). It is hard to see how the States’ role in regulating
water resources would remain “primary” if the EPA had ju-
risdiction over anything defined by the presence of water.
See County of Maui v. Hawaii Wildlife Fund, 590 U. S. ___,
___ (2020) (slip op., at 7); Rapanos, 547 U. S., at 737 (plu-
rality opinion).
B
Although the ordinary meaning of “waters” in §1362(7)
might seem to exclude all wetlands, we do not view that
provision in isolation. The meaning of a word “may only
become evident when placed in context,” FDA v. Brown &
Williamson Tobacco Corp., 529 U. S. 120, 132 (2000), and
statutory context shows that some wetlands qualify as “wa-
ters of the United States.”
In 1977, Congress amended the CWA and added
§1344(g)(1), which authorizes States to apply to the EPA for
permission to administer programs to issue permits for the
discharge of dredged or fill material into some bodies of wa-
ter. In simplified terms, the provision specifies that state
permitting programs may regulate discharges into (1) any
waters of the United States, (2) except for traditional navi-
gable waters, (3) “including wetlands adjacent thereto.”15
When this convoluted formulation is parsed, it tells us
that at least some wetlands must qualify as “waters of the
——————
15 This provision states in relevant part: “The Governor of any State

desiring to administer its own individual and general permit program for
the discharge of dredged or fill material into the navigable waters (other
than those waters which are presently used, or are susceptible to use in
their natural condition or by reasonable improvement as a means to
transport interstate or foreign commerce shoreward to their ordinary
high water mark, including all waters which are subject to the ebb and
flow of the tide shoreward to their mean high water mark, or mean
higher high water mark on the west coast, including wetlands adjacent
thereto) within its jurisdiction may submit to the Administrator a full
and complete description of the program it proposes to establish and ad-
minister under State law or under an interstate compact.” 33 U. S. C.
§1344(g)(1).
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Opinion of the Court

United States.” The provision begins with a broad category,
“the waters of the United States,” which we may call cate-
gory A. The provision provides that States may permit dis-
charges into these waters, but it then qualifies that States
cannot permit discharges into a subcategory of A: tradi-
tional navigable waters (category B). Finally, it states that
a third category (category C), consisting of wetlands “adja-
cent” to traditional navigable waters, is “includ[ed]” within
B. Thus, States may permit discharges into A minus B,
which includes C. If C (adjacent wetlands) were not part of
A (“the waters of the United States”) and therefore subject
to regulation under the CWA, there would be no point in
excluding them from that category. See Riverside Bayview,
474 U. S., at 138, n. 11 (recognizing that §1344(g) “at least
suggest[s] strongly that the term ‘waters’ as used in the Act
does not necessarily exclude ‘wetlands’ ”); Rapanos, 547
U. S., at 768 (opinion of Kennedy, J.). Thus, §1344(g)(1)
presumes that certain wetlands constitute “waters of the
United States.”
But what wetlands does the CWA regulate? Section
1344(g)(1) cannot answer that question alone because it is
not the operative provision that defines the Act’s reach.
See Riverside Bayview, 474 U. S., at 138, n. 11. Instead, we
must harmonize the reference to adjacent wetlands in
§1344(g)(1) with “the waters of the United States,”
§1362(7), which is the actual term we are tasked with inter-
preting. The formulation discussed above tells us how: be-
cause the adjacent wetlands in §1344(g)(1) are “includ[ed]”
within “the waters of the United States,” these wetlands
must qualify as “waters of the United States” in their own
right. In other words, they must be indistinguishably part
of a body of water that itself constitutes “waters” under the
CWA. See supra, at 14.
This understanding is consistent with §1344(g)(1)’s use of
“adjacent.” Dictionaries tell us that the term “adjacent”
may mean either “contiguous” or “near.” Random House
20 SACKETT v. EPA

Opinion of the Court

Dictionary 25; see Webster’s Third New International Dic-
tionary 26 (1976); see also Oxford American Dictionary &
Thesaurus 16 (2d ed. 2009) (listing “adjoining” and “neigh-
boring” as synonyms of “adjacent”). But “construing statu-
tory language is not merely an exercise in ascertaining ‘the
outer limits of a word’s definitional possibilities,’ ” FCC v.
AT&T Inc., 562 U. S. 397, 407 (2011) (alterations omitted),
and here, “only one . . . meanin[g] produces a substantive
effect that is compatible with the rest of the law,” United
Sav. Assn. of Tex. v. Timbers of Inwood Forest Associates,
Ltd., 484 U. S. 365, 371 (1988). Wetlands that are separate
from traditional navigable waters cannot be considered
part of those waters, even if they are located nearby.
In addition, it would be odd indeed if Congress had tucked
an important expansion to the reach of the CWA into con-
voluted language in a relatively obscure provision concern-
ing state permitting programs. We have often remarked
that Congress does not “hide elephants in mouseholes” by
“alter[ing] the fundamental details of a regulatory scheme
in vague terms or ancillary provisions.” Whitman v. Amer-
ican Trucking Assns., Inc., 531 U. S. 457, 468 (2001). We
cannot agree with such an implausible interpretation here.
If §1344(g)(1) were read to mean that the CWA applies to
wetlands that are not indistinguishably part of otherwise
covered “waters of the United States,” see supra, at 14, it
would effectively amend and substantially broaden
§1362(7) to define “navigable waters” as “waters of the
United States and adjacent wetlands.” But §1344(g)(1)’s
use of the term “including” makes clear that it does not pur-
port to do—and in fact, does not do—any such thing. See
National Assn. of Home Builders v. Defenders of Wildlife,
551 U. S. 644, 662–664, and n. 8 (2007) (recognizing that
implied amendments require “ ‘clear and manifest’ ” evi-
dence of congressional intent). It merely reflects Congress’s
assumption that certain “adjacent” wetlands are part of
“waters of the United States.”
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Opinion of the Court

This is the thrust of observations in decisions going all
the way back to Riverside Bayview. In that case, we de-
ferred to the Corps’ decision to regulate wetlands actually
abutting a navigable waterway, but we recognized “the in-
herent difficulties of defining precise bounds to regulable
waters.” 474 U. S., at 134; see also id., at 132 (noting that
“the transition from water to solid ground is not necessarily
or even typically an abrupt one” due to semi-aquatic fea-
tures like shallows and swamps). In such a situation, we
concluded, the Corps could reasonably determine that wet-
lands “adjoining bodies of water” were part of those waters.
Id., at 135, and n. 9; see also SWANCC, 531 U. S., at 167
(recognizing that Riverside Bayview “held that the Corps
had . . . jurisdiction over wetlands that actually abutted on
a navigable waterway”).
In Rapanos, the plurality spelled out clearly when adja-
cent wetlands are part of covered waters. It explained that
“waters” may fairly be read to include only those wetlands
that are “as a practical matter indistinguishable from wa-
ters of the United States,” such that it is “difficult to deter-
mine where the ‘water’ ends and the ‘wetland’ begins.” 547
U. S., at 742, 755 (emphasis deleted). 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.” Id., at 742; cf. 33 U. S. C. §2802(5) (defining
“coastal waters” to include wetlands “having unimpaired
connection with the open sea up to the head of tidal influ-
ence”). We agree with this formulation of when wetlands
are part of “the waters of the United States.” We also
acknowledge that temporary interruptions in surface con-
nection may sometimes occur because of phenomena like
low tides or dry spells.16
——————
16 Although a barrier separating a wetland from a water of the United

States would ordinarily remove that wetland from federal jurisdiction, a
22 SACKETT v. EPA

Opinion of the Court

In sum, we hold that the CWA extends to only those wet-
lands that are “as a practical matter indistinguishable from
waters of the United States.” Rapanos, 547 U. S., at 755
(plurality opinion) (emphasis deleted). This requires the
party asserting jurisdiction over adjacent wetlands to es-
tablish “first, that the adjacent [body of water constitutes]
. . . ‘water[s] of the United States,’ (i.e., a relatively perma-
nent body of water connected to traditional interstate nav-
igable waters); and second, that the wetland has a continu-
ous surface connection with that water, making it difficult
to determine where the ‘water’ ends and the ‘wetland’ be-
gins.” Id., at 742.
IV
The EPA resists this reading of §1362(7) and instead asks
us to defer to its understanding of the CWA’s jurisdictional
reach, as set out in its most recent rule defining “the waters
of the United States.” See 88 Fed. Reg. 3004. This rule, as
noted, provides that “adjacent wetlands are covered by the
Act if they ‘possess a “significant nexus” to’ traditional nav-
igable waters.” Brief for Respondents 32 (quoting Rapanos,
547 U. S., at 759 (opinion of Kennedy, J.)); see 88 Fed. Reg.
3143. And according to the EPA, wetlands are “adjacent”
when they are “neighboring” to covered waters, even if they
are separated from those waters by dry land. Brief for Re-
spondents 20; 88 Fed. Reg. 3144.
A
For reasons already explained, this interpretation is in-
consistent with the text and structure of the CWA. Beyond
that, it clashes with “background principles of construction”

——————
landowner cannot carve out wetlands from federal jurisdiction by ille-
gally constructing a barrier on wetlands otherwise covered by the CWA.
Whenever the EPA can exercise its statutory authority to order a bar-
rier’s removal because it violates the Act, see 33 U. S. C. §§1319(a)–(b),
that unlawful barrier poses no bar to its jurisdiction.
 Cite as: 598 U. S. ____ (2023) 23

Opinion of the Court

that apply to the interpretation of the relevant statutory
provisions. Bond, 572 U. S., at 857. Under those presump-
tions, the EPA must provide clear evidence that it is author-
ized to regulate in the manner it proposes.
1
First, this Court “require[s] Congress to enact exceed-
ingly clear language if it wishes to significantly alter the
balance between federal and state power and the power of
the Government over private property.” United States For-
est Service v. Cowpasture River Preservation Assn., 590
U. S. ___, ___–___ (2020) (slip op., at 15–16); see also Bond,
572 U. S., at 858. Regulation of land and water use lies at
the core of traditional state authority. See, e.g., SWANCC,
531 U. S., at 174 (citing Hess v. Port Authority Trans-Hud-
son Corporation, 513 U. S. 30, 44 (1994)); Tarrant Regional
Water Dist. v. Herrmann, 569 U. S. 614, 631 (2013). An
overly broad interpretation of the CWA’s reach would im-
pinge on this authority. The area covered by wetlands
alone is vast—greater than the combined surface area of
California and Texas. And the scope of the EPA’s concep-
tion of “the waters of the United States” is truly staggering
when this vast territory is supplemented by all the addi-
tional area, some of which is generally dry, over which the
Agency asserts jurisdiction. Particularly given the CWA’s
express policy to “preserve” the States’ “primary” authority
over land and water use, §1251(b), this Court has required
a clear statement from Congress when determining the
scope of “the waters of the United States.” SWANCC, 531
U. S., at 174; accord, Rapanos, 547 U. S., at 738 (plurality
opinion).
The EPA, however, offers only a passing attempt to
square its interpretation with the text of §1362(7), and its
“significant nexus” theory is particularly implausible. It
suggests that the meaning of “the waters of the United
24 SACKETT v. EPA

Opinion of the Court

States” is so “broad and unqualified” that, if viewed in iso-
lation, it would extend to all water in the United States.
Brief for Respondents 32. The EPA thus turns to the “sig-
nificant nexus” test in order to reduce the clash between its
understanding of “the waters of the United States” and the
term defined by that phrase, i.e., “navigable waters.” As
discussed, however, the meaning of “waters” is more limited
than the EPA believes. See supra, at 14. And, in any event,
the CWA never mentions the “significant nexus” test, so the
EPA has no statutory basis to impose it. See Rapanos, 547
U. S., at 755–756 (plurality opinion).
2
Second, the EPA’s interpretation gives rise to serious
vagueness concerns in light of the CWA’s criminal penal-
ties. Due process requires Congress to define penal statutes
“ ‘with sufficient definiteness that ordinary people can un-
derstand what conduct is prohibited’ ” and “ ‘in a manner
that does not encourage arbitrary and discriminatory en-
forcement.’ ” McDonnell v. United States, 579 U. S. 550, 576
(2016) (quoting Skilling v. United States, 561 U. S. 358,
402–403 (2010)). Yet the meaning of “waters of the United
States” under the EPA’s interpretation remains “hopelessly
indeterminate.” Sackett, 566 U. S., at 133 (ALITO, J., con-
curring); accord, Hawkes Co., 578 U. S., at 602 (opinion of
Kennedy, J.).
The EPA contends that the only thing preventing it from
interpreting “waters of the United States” to “conceivably
cover literally every body of water in the country” is the
significant-nexus test. Tr. of Oral Arg. 70–71; accord, Brief
for Respondents 32. But the boundary between a “signifi-
cant” and an insignificant nexus is far from clear. And to
add to the uncertainty, the test introduces another vague
concept—“similarly situated” waters—and then assesses
the aggregate effect of that group based on a variety of
open-ended factors that evolve as scientific understandings
 Cite as: 598 U. S. ____ (2023) 25

Opinion of the Court

change. This freewheeling inquiry provides little notice to
landowners of their obligations under the CWA. Facing se-
vere criminal sanctions for even negligent violations, prop-
erty owners are “left ‘to feel their way on a case-by-case ba-
sis.’ ” Sackett, 566 U. S., at 124 (quoting Rapanos, 547 U. S.,
at 758 (ROBERTS, C. J., concurring)). Where a penal statute
could sweep so broadly as to render criminal a host of what
might otherwise be considered ordinary activities, we have
been wary about going beyond what “Congress certainly in-
tended the statute to cover.” Skilling, 561 U. S., at 404.
Under these two background principles, the judicial task
when interpreting “the waters of the United States” is to
ascertain whether clear congressional authorization exists
for the EPA’s claimed power. The EPA’s interpretation falls
far short of that standard.
B
While mustering only a weak textual argument, the EPA
justifies its position on two other grounds. It primarily
claims that Congress implicitly ratified its interpretation of
“adjacent” wetlands when it adopted §1344(g)(1). Thus, it
argues that “waters of the United States” covers any wet-
lands that are “bordering, contiguous, or neighboring” to
covered waters. 88 Fed. Reg. 3143. The principal opinion
concurring in the judgment adopts the same position. See
post, at 10–12 (KAVANAUGH, J., concurring in judgment).
The EPA notes that the Corps had promulgated regulations
adopting that interpretation before Congress amended the
CWA in 1977 to include the reference to “adjacent” wet-
lands in §1344(g)(1). See 42 Fed. Reg. 37144. This term,
the EPA contends, was “ ‘ “obviously transplanted from” ’ ”
the Corps’ regulations and thus incorporates the same def-
inition. Brief for Respondents 22 (quoting Taggart v. Lo-
renzen, 587 U. S. ___, ___ (2019) (slip op., at 5)).
This argument fails for at least three reasons. First, as
we have explained, the text of §§1362(7) and 1344(g)(1)
26 SACKETT v. EPA

Opinion of the Court

shows that “adjacent” cannot include wetlands that are not
part of covered “waters.” See supra, at 22.
Second, this ratification theory cannot be reconciled with
our cases. We have repeatedly recognized that §1344(g)(1)
“ ‘does not conclusively determine the construction to be
placed on . . . the relevant definition of “navigable wa-
ters.” ’ ” SWANCC, 531 U. S., at 171 (quoting Riverside
Bayview, 474 U. S., at 138, n. 11); accord, Rapanos, 547
U. S., at 747–748, n. 12 (plurality opinion). Additionally,
SWANCC rejected the closely analogous argument that
Congress ratified the Corps’ definition of “waters of the
United States” by including “ ‘other . . . waters’ ” in
§1344(g)(1). 531 U. S., at 168–171. And yet, the EPA’s ar-
gument would require us to hold that §1344(g)(1) actually
did amend the definition of “navigable waters” precisely for
the reasons we rejected in SWANCC.
Third, the EPA cannot provide the sort of “overwhelming
evidence of acquiescence” necessary to support its argu-
ment in the face of Congress’s failure to amend §1362(7).
Id., at 169–170, n. 5. We will infer that a term was “ ‘trans-
planted from another legal source’ . . . only when a term’s
meaning was ‘well-settled’ before the transplantation.”
Kemp v. United States, 596 U. S. ___, ___–___ (2022) (slip
op., at 9–10). Far from being well settled, the Corps’ defini-
tion was promulgated mere months before the CWA became
law, and when the Corps adopted that definition, it can-
didly acknowledged the “rapidly changing nature of [its]
regulatory programs.” 42 Fed. Reg. 37122. Tellingly, even
the EPA would not adopt that definition for several more
years. See 45 Fed. Reg. 85345 (1980). This situation is a
far cry from any in which we have found ratification. See,
e.g., George v. McDonough, 596 U. S. ___, ___ (2022) (slip
op., at 5) (finding ratification when “Congress used an unu-
sual term that had a long regulatory history in [the] very
regulatory context” at issue).
The EPA also advances various policy arguments about
 Cite as: 598 U. S. ____ (2023) 27

Opinion of the Court

the ecological consequences of a narrower definition of ad-
jacent. But the CWA does not define the EPA’s jurisdiction
based on ecological importance, and we cannot redraw the
Act’s allocation of authority. See Rapanos, 547 U. S., at 756
(plurality opinion). “The Clean Water Act anticipates a
partnership between the States and the Federal Govern-
ment.” Arkansas v. Oklahoma, 503 U. S. 91, 101 (1992).
States can and will continue to exercise their primary au-
thority to combat water pollution by regulating land and
water use. See, e.g., Brief for Farm Bureau of Arkansas
et al. as Amici Curiae 17–27.
V
Nothing in the separate opinions filed by JUSTICE
KAVANAUGH and JUSTICE KAGAN undermines our analysis.
JUSTICE KAVANAUGH claims that we have “rewrit[ten]” the
CWA, post, at 12 (opinion concurring in judgment), and
JUSTICE KAGAN levels similar charges, post, at 3–4 (opinion
concurring in judgment). These arguments are more than
unfounded. We have analyzed the statutory language in
detail, but the separate opinions pay no attention whatso-
ever to §1362(7), the key statutory provision that limits the
CWA’s geographic reach to “the waters of the United
States.” Thus, neither separate opinion even attempts to
explain how the wetlands included in their interpretation
fall within a fair reading of “waters.” Textualist arguments
that ignore the operative text cannot be taken seriously.
VI
In sum, we hold that the CWA extends to only those “wet-
lands with a continuous surface connection to bodies that
are ‘waters of the United States’ in their own right,” so that
they are “indistinguishable” from those waters. Rapanos,
547 U. S., at 742, 755 (plurality opinion) (emphasis de-
leted); see supra, at 22. This holding compels reversal here.
The wetlands on the Sacketts’ property are distinguishable
28 SACKETT v. EPA

Opinion of the Court

from any possibly covered waters.
* * *
We reverse the judgment of the United States Court of
Appeals for the Ninth Circuit and remand the case for fur-
ther proceedings consistent with this opinion.

It is so ordered.
 Cite as: 598 U. S. ____ (2023) 1

THOMAS, J., concurring

SUPREME COURT OF THE UNITED STATES
_________________

No. 21–454
_________________

MICHAEL SACKETT, ET UX., PETITIONERS v.
ENVIRONMENTAL PROTECTION
AGENCY, ET AL.
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE NINTH CIRCUIT
[May 25, 2023]

JUSTICE THOMAS, with whom JUSTICE GORSUCH joins,
concurring.
I join the Court’s opinion in full. The Clean Water Act
(CWA) confines the Federal Government’s jurisdiction to
“ ‘navigable waters,’ ” defined as “the waters of the United
States.” 33 U. S. C. §§1311(a), 1362(7), (12). And the Court
correctly holds that the term “waters” reaches “ ‘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.” ’ ” Ante, at 14 (quoting Rapanos v. United States,
547 U. S. 715, 739 (2006) (plurality opinion)). It also cor-
rectly holds that for a wetland to fall within this definition,
it must share a “ ‘continuous surface connection to bodies
that are “waters of the United States” in their own right’ ”
such that “ ‘there is no clear demarcation between “waters”
and wetlands.’ ” Ante, at 21 (quoting Rapanos, 547 U. S., at
742 (plurality opinion)).
However, like the Rapanos plurality before it, the Court
focuses only on the term “waters”; it does not determine the
extent to which the CWA’s other jurisdictional terms—
“navigable” and “of the United States”—limit the reach of
the statute. Ante, at 14–18; Rapanos, 547 U. S., at 731 (plu-
rality opinion). I write separately to pick up where the
2 SACKETT v. EPA

THOMAS, J., concurring

Court leaves off.
I
The CWA’s jurisdictional terms have a long pedigree and
are bound up with Congress’ traditional authority over the
channels of interstate commerce. Solid Waste Agency of
Northern Cook Cty. v. Army Corps of Engineers, 531 U. S.
159, 168, and n. 3, 172, 173–174 (2001) (SWANCC). That
traditional authority was limited in two ways. First, the
water had to be capable of being used as a highway for in-
terstate or foreign commerce. Second, Congress could reg-
ulate such waters only for purposes of their navigability—
by, for example, regulating obstructions hindering naviga-
ble capacity. By the time of the CWA’s enactment, the New
Deal era arguably had relaxed the second limitation; Con-
gress could regulate navigable waters for a wider range of
purposes. But, critically, the statutory terms “navigable
waters,” “navigable waters of the United States,” and “wa-
ters of the United States” were still understood as invoking
only Congress’ authority over waters that are, were, or
could be used as highways of interstate or foreign com-
merce. The CWA was enacted, and must be understood,
against that key backdrop.
A
As the Court correctly states, “land and water use lies at
the core of traditional state authority.” Ante, at 23; see also
ante, at 2. Prior to Independence, the Crown possessed sov-
ereignty over navigable waters in the Colonies, sometimes
held in trust by colonial authorities. See R. Adler, The An-
cient Mariner of Constitutional Law: The Historical, Yet
Declining Role of Navigability, 90 Wash. U. L. Rev. 1643,
1656–1659 (2013); R. Walston, The Federal Commerce and
Navigation Powers: Solid Waste Agency of Northern Cook
County’s Undecided Constitutional Issue, 42 Santa Clara
L. Rev. 699, 721 (2002) (Walston). Upon Independence, this
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THOMAS, J., concurring

sovereignty was transferred to each of the 13 fully sovereign
States. See Martin v. Lessee of Waddell, 16 Pet. 367, 410
(1842) (“[W]hen the Revolution took place, the people of
each state became themselves sovereign; and in that char-
acter hold the absolute right to all their navigable waters
and the soils under them for their own common use, subject
only to the rights since surrendered by the Constitution to
the general government”). Thus, today, States enjoy pri-
mary sovereignty over their waters, including navigable
waters—stemming either from their status as independent
sovereigns following Independence, ibid., or their later ad-
mission to the Union on an equal footing with the original
States, see Lessee of Pollard v. Hagan, 3 How. 212, 230
(1845) (“The shores of navigable waters, and the soils under
them, were not granted by the Constitution to the United
States, but were reserved to the states respectively. . . . The
new states have the same rights, sovereignty, and jurisdic-
tion over this subject as the original states”); see also M.
Starr, Navigable Waters of the United States—State and
National Control, 35 Harv. L. Rev. 154, 169–170 (1921).
The Federal Government therefore possesses no authority
over navigable waters except that granted by the Constitu-
tion.
The Federal Government’s authority over certain naviga-
ble waters is granted and limited by the Commerce Clause,
which grants Congress power to “regulate Commerce with
foreign Nations, and among the several States, and with
the Indian Tribes.” Art. I, §8, cl. 3. From the beginning, it
was understood that “[t]he power to regulate commerce, in-
cludes the power to regulate navigation,” but only “as con-
nected with the commerce with foreign nations, and among
the states.” United States v. Coombs, 12 Pet. 72, 78 (1838)
(Story, J., for the Court); accord, Gibbons v. Ogden, 9
Wheat. 1, 190 (1824) (“All America understands . . . the
word ‘commerce,’ to comprehend navigation. It was so un-
4 SACKETT v. EPA

THOMAS, J., concurring

derstood, and must have been so understood, when the con-
stitution was framed”); see also R. Barnett, The Original
Meaning of the Commerce Clause, 68 U. Chi. L. Rev. 101,
125–126 (2001) (Barnett); R. Natelson, The Legal Meaning
of “Commerce” in the Commerce Clause, 80 St. John’s
L. Rev. 789, 807–810 (2006). In fact, “shipping . . . was at
that time the indispensable means for the movement of
goods.” Barnett 123. The Commerce Clause thus vests
Congress with a limited authority over what we now call
the “channels of interstate commerce.” United States v.
Lopez, 514 U. S. 549, 558–559 (1995); see also American
Trucking Assns., Inc. v. Los Angeles, 569 U. S. 641, 656–657
(2013) (THOMAS, J., concurring).
This federal authority, however, does not displace States’
traditional sovereignty over their waters. “The power to
regulate commerce comprehends the control for that pur-
pose, and to the extent necessary, of all the navigable wa-
ters of the United States which are accessible from a State
other than those in which they lie.” Gilman v. Philadel-
phia, 3 Wall. 713, 724–725 (1866) (emphasis added). And,
traditionally, this limited authority was confined to regula-
tion of the channels of interstate commerce themselves.
Corfield v. Coryell, 6 F. Cas. 546, 550–551 (No. 3,230) (CC
ED Pa. 1823) (Washington, J., for the Court). It encom-
passed only “the power to keep them open and free from any
obstruction to their navigation” and “to remove such ob-
structions when they exist.” Gilman, 3 Wall., at 725. Thus,
any activity that “interferes with, obstructs, or prevents
such commerce and navigation, though done on land, may
be punished by congress.” Coombs, 12 Pet., at 78. But, ac-
tivities that merely “affect” water-based commerce, such as
those regulated by “[i]nspection laws, quarantine laws,
health laws of every description, as well as laws for regu-
lating the internal commerce of a State,” are not within
Congress’ channels-of-commerce authority. Gibbons, 9
Wheat., at 203; see also Corfield, 6 F. Cas., at 550.
 Cite as: 598 U. S. ____ (2023) 5

THOMAS, J., concurring

This understanding of the limits of Congress’ channels-
of-commerce authority prevailed through the end of the
19th century. The Court’s cases consistently recognized
that Congress has authority over navigable waters for only
the limited “purpose of regulating and improving naviga-
tion.” Gibson v. United States, 166 U. S. 269, 271–272
(1897); see also Port of Seattle v. Oregon & Washington
R. Co., 255 U. S. 56, 63 (1921) (“The right of the United
States in the navigable waters within the several States is
limited to the control thereof for purposes of navigation”).
And, this Court was careful to reaffirm that “technical title
to the beds of the navigable rivers of the United States is
either in the States in which the rivers are situated, or in
the owners of the land bordering upon such rivers” as de-
termined by “local law.” United States v. Chandler-Dunbar
Water Power Co., 229 U. S. 53, 60 (1913).
The River and Harbor Acts of 1890, 1894, and 1899 illus-
trate the limits of the channels-of-commerce authority. The
1890 Act authorizes the Secretary of War to “prohibi[t]” “the
creation of any obstruction, not affirmatively authorized by
law, to the navigable capacity of any waters, in respect of
which the United States has jurisdiction.” §10, 26 Stat.
454. The 1894 Act made it unlawful to deposit matter into
“any harbor or river of the United States” that the Federal
Government has appropriated money to improve and pro-
hibited injuring improvements built by the United States
in “any of its navigable waters.” §6, 28 Stat. 363.
Congress consolidated and expanded these authorities in
the 1899 Act. Section 10 of the Act prohibits “[t]he creation
of any obstruction . . . to the navigable capacity of any of the
waters of the United States,” requires a permit to build
“structures in any . . . water of the United States,” and
makes it unlawful “to excavate or fill, or in any manner to
alter or modify the course, location, condition, or capacity”
of any water, “within the limits of any breakwater, or of the
channel of any navigable water of the United States.” 30
6 SACKETT v. EPA

THOMAS, J., concurring

Stat. 1151 (codified, as amended, at 33 U. S. C. §403). In
addition, §13 of the Act, sometimes referred to as the “Re-
fuse Act,” prohibits throwing, discharging, or depositing
“any refuse matter . . . into any navigable water of the
United States, or into any tributary of any navigable water
from which the same shall float or be washed into such nav-
igable water.” 30 Stat. 1152 (codified, as amended, at 33
U. S. C. §407). Section 13 also prohibits depositing mate-
rial “on the bank of any navigable water, or on the bank of
any tributary of any navigable water, where the same shall
be liable to be washed into such navigable water . . .
whereby navigation shall or may be impeded or obstructed.”
Ibid.
Three things stand out about these provisions. First,
they use the terms “navigable water,” “water of the United
States,” and “navigable water of the United States” inter-
changeably. 33 U. S. C. §§403 and 407; see also V. Albrecht
& S. Nickelsburg, Could SWANCC Be Right? A New Look
at the Legislative History of the Clean Water Act, 32 Env.
L. Rev. 11042, 11044 (2002) (Albrecht & Nickelsburg). As
a result, courts have done the same in decisions interpret-
ing the River and Harbor Acts. See, e.g., United States v.
Stoeco Homes, Inc., 498 F. 2d 597, 608–609 (CA3 1974);
New England Dredging Co. v. United States, 144 F. 932,
933–934 (CA1 1906); Blake v. United States, 181 F. Supp.
584, 587–588 (ED Va. 1960).
Second, Congress asserted its authority only to the extent
that obstructions or refuse matter could impede navigation
or navigable capacity. Thus, in United States v. Rio Grande
Dam & Irrigation Co., 174 U. S. 690 (1899), this Court rec-
ognized that any “act sought to be enjoined” under the 1890
Act must be “one which fairly and directly tends to obstruct
(that is, interfere with or diminish) the navigable capacity
of a stream.” Id., at 709; accord, Lake Shore & Michigan
Southern R. Co. v. Ohio, 165 U. S. 365, 369 (1897) (holding
 Cite as: 598 U. S. ____ (2023) 7

THOMAS, J., concurring

that federal jurisdiction over “navigable waters” was lim-
ited to preventing “interfering with commerce”). Similarly,
in Wisconsin v. Illinois, 278 U. S. 367 (1929), this Court in-
terpreted the 1899 Act in light of the constitutional prohi-
bition on Congress “arbitrarily destroy[ing] or impair[ing]
the rights of riparian owners by legislation which has no
real or substantial relation to the control of navigation or
appropriateness to that end.” Id., at 415.1 The touchstone,
thus, remained actual navigation.
Third, §13 of the Act requires some form of surface water
connection between a tributary and traditionally navigable
waters. See 33 U. S. C. §407 (prohibiting depositing refuse
“into any tributary of any navigable water from which the
same shall float or be washed into such navigable water”).
To be sure, the Refuse Act also prohibits leaving refuse “on
the bank of any navigable water, or on the bank of any trib-
utary of any navigable water, where the same shall be liable
to be washed into such navigable water.” Ibid. But, this
prohibition reflects nothing more than Congress’ tradi-
tional authority to regulate acts done on land that directly
impair the navigability of traditionally navigable waters.
See Rio Grande Dam & Irrigation Co., 174 U. S., at 708 (ex-
plaining that the Act reaches “any obstruction to the navi-
gable capacity, and anything, wherever done or however
——————
1 Courts had long carefully enforced limits on Congress’ navigation au-

thority in prosecutions brought under the Act of July 7, 1838, ch. 191, 5
Stat. 304 (Steamboat Acts of 1838), which prohibited the transportation
of goods “upon the bays, lakes, rivers, or other navigable waters of the
United States” by certain steamboats. See, e.g., The Seneca, 27 F. Cas.
1021 (No. 16,251) (DC Wis. 1861); see also The James Morrison, 26
F. Cas. 579, 582 (No. 15,465) (DC Mo. 1846) (holding that the 1838 Act
did not reach a ship whose “employment ha[d] no other than a remote
connection with ‘commerce or navigation among the several states;’ no
more connection than has the farmer who cultivates hemp, tobacco or
cotton for a market in other states—the miner who digs and smelts
lead—the manufacturer who manufactures for the same market, or the
traveler who intends purchasing any of these articles”).
8 SACKETT v. EPA

THOMAS, J., concurring

done, . . . which tends to destroy the navigable capacity of
one of the navigable waters of the United States”); see also
Northern Pacific R. Co. v. United States, 104 F. 691, 693
(CA8 1900); Coombs, 12 Pet., at 78. It does not mean that
the land itself is a navigable water.2
The history of federal regulation of navigable waters
demonstrates that Congress’ authority over navigation, as
traditionally understood, was narrow but deep. It only ap-
plied to a discrete set of navigable waters and could only be
used to keep those waters open for interstate commerce.
See Port of Seattle, 255 U. S., at 63; Rio Grande Dam & Ir-
rigation Co., 174 U. S., at 709. Yet, where Congress had
authority, it displaced the States’ traditional sovereignty
over their navigable waters and allowed Congress to regu-
late activities even on land that could directly cause ob-
structions to navigable capacity. Gilman, 3 Wall., at 724–
725; Coombs, 12 Pet., at 78.
In light of the depth of this new federal power, it was
carefully limited—mere “effects” on interstate commerce
were not sufficient to trigger Congress’ navigation author-
ity. As one District Court presciently observed in interpret-
ing the term “navigable waters of the United States” in the
Steamboat Act of 1838:
“To make a particular branch of commerce or trade
within a state, a part of the commerce among the sev-
eral states, it would not be sufficient that it was re-
motely connected with that commerce among the sev-
eral states; for almost everything and every occupation
and employment in life are remotely connected with
——————
2 The early 20th century also saw the Reclamation Act of 1902, ch.

1093, 32 Stat. 388; Federal Power Act, ch. 285, 41 Stat. 1063; Oil Pollu-
tion Act, 1924, ch. 316, 43 Stat. 604; and Flood Control Act of 1936, ch.
688, 49 Stat. 1570, all of which relied on navigability. See Walston 724–
726. Although the Acts were also designed to achieve incidental benefits
such as pollution control, Congress located its authority in preserving
navigation. Ibid.
 Cite as: 598 U. S. ____ (2023) 9

THOMAS, J., concurring

that commerce or navigation. And if congress has the
right to regulate every employment or pursuit thus re-
motely connected with that commerce, of which they
have the control, then it has the right to regulate nearly
the entire business and employment of the citizens of
the several states. . . . Yet, if congress has the power to
regulate all these employments, and a thousand others
equally connected with that commerce, then it can reg-
ulate nearly all the concerns of life, and nearly all the
employments of the citizens of the several states; and
the state governments might as well be abolished. It is
not sufficient, then, that navigation, or trade, or busi-
ness of any kind, within a state, be remotely connected,
or, perhaps, connected at all with ‘commerce with for-
eign nations, or among the several states, or with the
Indian tribes,’ it should be a part of that commerce, to
authorize congress to regulate it.” The James Morri-
son, 26 F. Cas. 579, 581 (No. 15,465) (DC Mo. 1846).
The Court’s observation that “federal regulation was
largely limited to ensuring that ‘traditional navigable wa-
ters’ . . . remained free of impediments,” ante, at 2, thus
does no more than reflect the original understanding of the
federal authority over navigable waters.
B
As noted above, the scope of Congress’ authority over wa-
ters was defined by the traditional concept of navigability,
imported with significant modifications from the English
common law.3 Thus, Congress could regulate only “naviga-

——————
3 The English rule tied navigability to the ebb and flow of the tides, but

began to be eroded in America as early as the Northwest Ordinance of
1787 due to the superior commercial capacity of American inland rivers.
See The Daniel Ball, 10 Wall. 557, 563 (1871); Propeller Genesee Chief v.
Fitzhugh, 12 How. 443, 454–457 (1852); see also Economy Light & Power
10 SACKETT v. EPA

THOMAS, J., concurring

ble waters.” Consistent with that backdrop, the term “nav-
igable waters”—used interchangeably with “waters of the
United States” and “navigable waters of the United
States”—referred to the waters subject to Congress’ tradi-
tional authority over navigable waters until the enactment
of the CWA.
1
The term “navigable waters” has been in use since the
founding to refer to the highways of commerce that were
key to the Nation’s development. Great cities like Philadel-
phia and St. Louis emerged at first as commercial ports
along these navigable waters. The Framers recognized that
“Providence has in a particular manner blessed” our coun-
try with “[a] succession of navigable waters” that “bind [the
Nation] together; while the most noble rivers in the world,
running at convenient distances, present [Americans] with
highways for the easy communication of friendly aids and
the mutual transportation and exchange of their various
commodities.” The Federalist No. 2, p. 38 (C. Rossiter ed.
1961) (J. Jay). These “vast rivers, stretching far inland”
have been of “transcendent importance” to our Nation’s eco-
nomic expansion by forming “great highways” for com-
merce. L. Houck, Law of Navigable Rivers xiii (1868).
This Court authoritatively set out the scope of the term
“navigable waters of the United States” in the seminal case
of The Daniel Ball, 10 Wall. 557 (1871). That case arose
under the Steamboat Act of 1838, which prohibited the
transportation of goods “upon the bays, lakes, rivers, or
other navigable waters of the United States.” §2, 5 Stat.

——————
Co. v. United States, 256 U. S. 113, 120 (1921) (“[I]t is curious and inter-
esting that the importance of these inland waterways, and the inappro-
priateness of the tidal test in defining our navigable waters, was thus
recognized by the Congress of the Confederation [in the Northwest Ordi-
nance] more than 80 years before this court decided The Daniel Ball . . .
and more than 60 years before The Propeller Genesee Chief ”).
 Cite as: 598 U. S. ____ (2023) 11

THOMAS, J., concurring

304. This Court held that the term “navigable” refers to
waters that are “navigable in fact,” meaning that “they are
used, or are susceptible of being used, in their ordinary con-
dition, as highways for commerce, over which trade and
travel are or may be conducted in the customary modes of
trade and travel on water.” The Daniel Ball, 10 Wall., at
563. The Court then explained that navigable waters are
“of the United States,” “in contradistinction from the navi-
gable waters of the States, when they form in their ordinary
condition by themselves, or by uniting with other waters, a
continued highway over which commerce is or may be car-
ried on with other States or foreign countries in the custom-
ary modes in which such commerce is conducted by water.”
Ibid.; see also The Montello, 11 Wall. 411, 415 (1871) (“If . . .
the river is not of itself a highway for commerce with other
States or foreign countries, or does not form such highway
by its connection with other waters, and is only navigable
between different places within the State, then it is not a
navigable water of the United States, but only a navigable
water of the State”). It is this “junction” between waters to
“for[m] a continued highway for commerce, both with other
States and with foreign countries,” that brings the water
“under the direct control of Congress in the exercise of its
commercial power.” The Daniel Ball, 10 Wall., at 564. The
definition of a “navigable water of the United States” was
thus linked directly to the limits on Congress’ commerce au-
thority: A navigable water of the United States was one
that was ordinarily used for interstate or foreign commerce.
Wetlands were generally excluded from this definition.
In Leovy v. United States, 177 U. S. 621 (1900), for example,
the Court employed the Daniel Ball test to hold that the
term “navigable waters of the United States,” as used in the
1890 River and Harbor Act, did not “prevent the exercise by
the State of Louisiana of its power to reclaim swamp and
overflowed lands by regulating and controlling the current
12 SACKETT v. EPA

THOMAS, J., concurring

of small streams not used habitually as arteries of inter-
state commerce.” 177 U. S., at 632. The Court observed
that applying the Act to wetlands reclamation “would ex-
tend the paramount jurisdiction of the United States over
all the flowing waters in the States.” Id., at 633. “If such
were the necessary construction of the” term “navigable wa-
ter,” the Court explained, the River and Harbor Act’s “va-
lidity might well be questioned.” Ibid. But, the Court de-
clined to interpret the Act to reach the wetlands, because it
recognized that the phrase “navigable waters of the United
States” encompassed only those waters reached by the tra-
ditional channels-of-commerce authority:
“When it is remembered that the source of the power of
the general government to act at all in this matter
arises out of its power to regulate commerce with for-
eign countries and among the States, it is obvious that
what the Constitution and the acts of Congress have in
view is the promotion and protection of commerce in its
international and interstate aspect, and a practical
construction must be put on these enactments as in-
tended for such large and important purposes.” Ibid.
The Court thus held that the mere use of a wetland by fish-
ermen was not sufficient to make the wetland a navigable
water of the United States; it “was not shown that passen-
gers were ever carried through it, or that freight destined
to any other State than Louisiana, or, indeed, destined for
any market in Louisiana, was ever, much less habitually,
carried through it.” Id., at 627.4

——————
4 Leovy v. United States also reflected the law’s longstanding hostility

to wetlands: “If there is any fact which may be supposed to be known by
everybody, and, therefore, by courts, it is that swamps and stagnant wa-
ters are the cause of malarial and malignant fevers, and that the police
power is never more legitimately exercised than in removing such nui-
sances.” 177 U. S., at 636. Traditionally, the only time wetlands were
the subject of federal legislation was to aid the States in draining them.
 Cite as: 598 U. S. ____ (2023) 13

THOMAS, J., concurring

The Daniel Ball test, with minor variations, marked the
limits of federal jurisdiction over waters up to the enact-
ment of the CWA. For instance, in Economy Light & Power
Co. v. United States, 256 U. S. 113 (1921), the Court applied
The Daniel Ball but expanded it to hold that the River and
Harbor Act of 1899 reaches waters that are not currently
capable of supporting interstate commerce, though they
once did. 256 U. S., at 123–124. And, in United States v.
Appalachian Elec. Power Co., 311 U. S. 377 (1940), the
Court applied The Daniel Ball to reach waters that could be
made navigable with reasonable and feasible improvement.
311 U. S., at 408–409. While these cases expanded the
outer boundaries of the term, creating an expanded form of
the Daniel Ball test, they reflect the Court’s longstanding
view that the statutory term “navigable water” required ap-
plication of the Daniel Ball test.
2
In the New Deal era, as is well known, this Court adopted
a greatly expanded conception of Congress’ commerce au-
thority by permitting Congress to regulate any private in-
trastate activity that substantially affects interstate com-
merce, either by itself or when aggregated with many
similar activities. See Wickard v. Filburn, 317 U. S. 111,
127–129 (1942); see also United States v. Darby, 312 U. S.
100, 119 (1941). Yet, this expansion did not fundamentally
change the Court’s understanding that the term “navigable
waters” referred to waters used for interstate commerce.
Thus, in Appalachian Elec., the Court continued to apply
the concept of navigability to determine the scope of Con-
gress’ Commerce Clause authority to require licenses under
——————
See, e.g., Swamp Land Act of 1850, ch. 84, 9 Stat. 519; see also S. John-
son, Wetlands Law: A Course Source 25–26 (2d ed. 2018). Wetlands
preservation only gained traction due, in large part, to advances in fire-
arms technology that made waterfowl hunting feasible. G. Baldassarre
& E. Bolen, Waterfowl Ecology and Management 10–14 (1994).
14 SACKETT v. EPA

THOMAS, J., concurring

the Federal Water Power Act for the construction of hydro-
electric dams in “navigable waters.” 311 U. S., at 406–410.
Only after applying the Daniel Ball definition to determine
that the river in question was navigable did the Court hold
that Congress had plenary authority over the erection of
structures in the river, regardless of whether the structure
actually impeded navigability. 311 U. S., at 423–426.
While this represented an expansive application of the old
concept that Congress can prevent obstructions to naviga-
ble capacity, see supra, at 4, 7–8, Appalachian Elec. made
clear that the term “navigable waters” remained tethered to
Congress’ traditional channels-of-commerce authority—not
to the broader conceptions of the commerce authority
adopted by the Court at that time.
The next year, in Oklahoma ex rel. Phillips v. Guy F. At-
kinson Co., 313 U. S. 508 (1941), the Court reaffirmed that
the term “navigable waters,” this time as used in the Flood
Control Act of 1936, was to be interpreted in light of the
expanded Daniel Ball test. 313 U. S., at 522–525. Signifi-
cantly, Oklahoma was decided mere months after Darby,
one of the most significant cases expanding the scope of the
commerce authority. 312 U. S., at 119. However, Okla-
homa did not so much as mention Darby in construing the
jurisdiction Congress conveyed in the term “navigable wa-
ters.” Instead, it cited Darby only in passing and to support
the argument that, once a river is deemed navigable under
the channels-of-commerce authority, Congress has author-
ity to protect “the nation’s arteries of commerce” by regulat-
ing intrastate activities on nonnavigable parts and tribu-
taries of the navigable river lest such activities “impai[r]
navigation itself.” Oklahoma, 313 U. S., at 525. This was
nothing more than an application of the principle that Con-
gress can regulate activities that obstruct navigable capac-
ity. Thus, even as the Court expanded the Commerce
Clause in other contexts, it continued to understand that
the term “navigable waters” refers solely to the aquatic
 Cite as: 598 U. S. ____ (2023) 15

THOMAS, J., concurring

channels of interstate commerce over which Congress tra-
ditionally exercised authority.
3
This understanding of the term “navigable waters”—i.e.,
as shorthand for waters subject to Congress’ authority un-
der the Daniel Ball test—persisted up to the enactment of
the CWA. See, e.g., Stoeco Homes, Inc., 498 F. 2d, at 608–
609; United States v. Joseph G. Moretti, Inc., 478 F. 2d 418,
428–429 (CA5 1973); see also D. Guinn, An Analysis of Nav-
igable Waters of the United States, 18 Baylor L. Rev. 559,
579 (1966) (“[T]he test of The Daniel Ball and Appalachian
Power Co. are religiously cited as being the basis for the
holding on the issue of navigability”). As a court observed
near the time of the CWA’s enactment, “[a]lthough the def-
inition of ‘navigability’ laid down in The Daniel Ball has
subsequently been modified and clarified, its definition of
‘navigable water of the United States,’ insofar as it requires
a navigable interstate linkage by water, appears to remain
unchanged.” Hardy Salt Co. v. Southern Pacific Transp.
Co., 501 F. 2d 1156, 1167 (CA10 1974) (citations omitted).
This Court’s cases, too, continued to apply traditional navi-
gability concepts in cases under the River and Harbor Acts
right up to the CWA’s enactment. See United States v.
Standard Oil Co., 384 U. S. 224, 226 (1966) (holding that
spilling oil in a navigable water was prohibited by the Re-
fuse Act (§13 of the 1899 Act) because “its presence in our
rivers and harbors is both a menace to navigation and a pol-
lutant”); United States v. Republic Steel Corp., 362 U. S.
482, 487–491 (1960) (“diminution of the navigable capacity
of a waterway” required for violation of the Refuse Act).
Thus, on the eve of the CWA’s enactment, the term “navi-
gable waters” meant those waters that are, were, or could
be used as highways of interstate or foreign commerce.
16 SACKETT v. EPA

THOMAS, J., concurring

II
This history demonstrates that Congress was not writing
on a blank slate in the CWA, which defines federal jurisdic-
tion using the same terms used in the River and Harbor
Acts: “navigable waters” and “the waters of the United
States,” 33 U. S. C. §§1311(a), 1362(7), (12). As explained
above, courts and Congress had long used the terms “navi-
gable water,” “navigable water of the United States,” and
“the waters of the United States” interchangeably to signify
those waters to which the traditional channels-of-commerce
authority extended. See supra, at 6. The terms “navigable
waters” and “waters of the United States” shared a core re-
quirement that the water be a “highway over which com-
merce is or may be carried,” with the term “of the United
States” doing the independent work of requiring that such
commerce “be carried on with other States or foreign coun-
tries.” The Daniel Ball, 10 Wall., at 563. The text of the
CWA thus reflects the traditional balance between federal
and state authority over navigable waters, as set out by The
Daniel Ball. It would be strange indeed if Congress sought
to effect a fundamental transformation of federal jurisdic-
tion over water through phrases that had been in use to de-
scribe the traditional scope of that jurisdiction for well over
a century and that carried a well-understood meaning.5
——————
5 In fact, when Congress has wished to depart from this traditional

meaning, it has done so expressly, as in parts of the Federal Power Act,
§23, 41 Stat. 1075 (requiring approval for dam construction “across,
along, over, or in any stream or part thereof, other than those defined
herein this chapter as navigable waters”); the Federal Water Pollution
Control Act, ch. 758, §2(a), 62 Stat. 1155 (as amended, 86 Stat. 816) (au-
thorizing federal-state cooperation to abate water pollution in “interstate
waters” and their tributaries); and the Water Quality Act of 1965, 79
Stat. 905–906 (authorizing grants to research abatement of pollution
into “any waters”); see Hardy Salt Co. v. Southern Pacific Transp. Co.,
501 F. 2d 1156, 1168 (CA10 1974) (noting that Congress only departs
from the expanded Daniel Ball test by using “clear and explicit lan-
guage,” as it did in parts of the Federal Power Act).
 Cite as: 598 U. S. ____ (2023) 17

THOMAS, J., concurring

The Army Corps of Engineers originally understood the
CWA in precisely this way. In its 1974 regulation estab-
lishing the first CWA §404 permitting program,6 the Corps
interpreted the term “the waters of the United States” to
establish jurisdiction over the traditional navigable waters
as determined by the expanded Daniel Ball test, noting also
that the term is limited by Congress’ navigation authority.
39 Fed. Reg. 12115. The Corps anchored its jurisdiction in
the expanded Daniel Ball test, defining “navigable waters”
to include “those waters of the United States which are sub-
ject to the ebb and flow of the tide, and/or are presently, or
have been in the past, or may be in the future susceptible
for use for purposes of interstate or foreign commerce.” 33
CFR §209.120(d)(1) (1974); see also §§209.260(d)(1)–(3) (re-
quiring “[p]ast, present, or potential presence of interstate
or foreign commerce,” “[p]hysical capabilities for use by
commerce,” and “[d]efined geographic limits of the water
body”). The regulations also made clear that traditional
navigability factors were the baseline for CWA jurisdiction:
“It is the water body’s capability of use by the public for
purposes of transportation or commerce which is the deter-
minative factor.” §209.260(e)(1).
Almost immediately, however, a few courts and the re-
cently created Environmental Protection Agency (EPA) re-
jected this interpretation. Instead, they interpreted the
CWA to assert the full extent of Congress’ New Deal era
authority to regulate anything that substantially affects in-
terstate commerce by itself or in the aggregate. See United
States v. Ashland Oil & Transp. Co., 504 F. 2d 1317, 1323–
1329 (CA6 1974); P. F. Z. Properties, Inc. v. Train, 393
F. Supp. 1370, 1381 (DC 1975); National Resource Defense
Council, Inc. v. Callaway, 392 F. Supp. 685, 686 (DC 1975);

——————
6 Section 404 authorizes the Corps to “issue permits . . . for the dis-

charge of dredged or fill material into the navigable waters at specified
disposal sites.” 33 U. S. C. §§1344(a), (d).
18 SACKETT v. EPA

THOMAS, J., concurring

United States v. Holland, 373 F. Supp. 665, 669, 672–674
(MD Fla. 1974); 40 CFR §125.1(o) (1974) (initial EPA CWA
definition). The courts that reached this conclusion relied
almost exclusively on legislative history and statutory pur-
pose. See, e.g., Holland, 373 F. Supp., at 672 (“The forego-
ing [legislative history] compels the Court to conclude that
the former test of navigability was indeed defined away in
the [CWA]”). But signals from legislative history cannot re-
but clear statutory text, and the text of the CWA employs
words that had long been universally understood to reach
only those waters subject to Congress’ channels-of-
commerce authority. See supra, at 15.
These courts and the EPA had only one textual hook for
their interpretation: In defining the term “navigable wa-
ters” as “the waters of the United States,” the CWA seemed
to drop the term “navigable” from the operative part of the
definition. Seizing on this phrasing, the EPA’s general
counsel asserted in 1973 that “the deletion of the word ‘nav-
igable’ eliminates the requirement of navigability. The only
remaining requirement, then, is that pollution of waters
covered by the bill must be capable of affecting interstate
commerce.” 1 EPA Gen. Counsel Op. 295 (1973). Similarly,
the District Court that vacated the Corps’ original CWA
definition held, without any analysis or citation, that the
term “the waters of the United States” in the CWA is “not
limited to the traditional tests of navigability.” National
Resource Defense Council, 392 F. Supp., at 671.
That interpretation cannot be right. For one, the terms
“navigable waters” and “the waters of the United States”
had long been used synonymously by courts and Congress.
The CWA simply used the terms in the same manner as the
River and Harbor Acts. Moreover, no source prior to the
CWA had ever asserted that the term “the waters of the
United States,” when not modified by “navigable,” reached
any water that may affect interstate commerce. Instead,
The Daniel Ball made clear that “[t]he phrase ‘waters of the
 Cite as: 598 U. S. ____ (2023) 19

THOMAS, J., concurring

United States, in contradistinction from the navigable wa-
ters of the States,’ . . . distinguishes interstate from intra-
state waters.” Albrecht & Nickelsburg 11049 (quoting The
Daniel Ball, 10 Wall., at 563); accord, 1 A. Knauth, Benedict
on Admiralty §44, p. 96 (6th ed. 1940) (“The inland lakes of
various States are navigable but, having no navigable out-
let linking them with our system of water-ways, have never
been held to be public waters of the United States” (empha-
sis added)). The text of the CWA extends jurisdiction to
“navigable waters,” and—precisely tracking The Daniel
Ball—clarifies that it reaches “the waters of the United
States,” rather than the navigable waters of the States.
Thus, the CWA’s use of the phrase “the waters of the
United States” reinforces, rather than lessens, the need for
a water to be at least part of “a continued highway over
which commerce is or may be carried on with other States
or foreign countries in the customary modes in which such
commerce is conducted by water.” The Daniel Ball, 10
Wall., at 563. At most, the omission of the word “navigable”
signifies that the CWA adopts the expanded Daniel Ball
test—that includes waters that are, have been, or can be
reasonably made navigable in fact—in its statutory provi-
sions. The Federal Government’s interpretation, by con-
trast, 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.” See Albrecht & Nickelsburg 11049 (“EPA’s conclu-
sion is ahistorical as well as illogical”).7 “[T]he waters of the
——————
7 To be sure, the CWA is more aggressive in regulating navigable wa-

ters than the River and Harbor Acts. But, the increased stringency is
not accomplished by expanding jurisdiction. The Acts use the same ju-
risdictional terms. Instead, the difference between them lies in the ex-
panded scope of activities that the CWA regulates and its shift from an
enforcement and injunctive regime to a previolation licensing regime.
See Albrecht & Nickelsburg 11046. I express no view on the constitu-
tionality of this regime as applied to navigable waters or on the Court’s
holding in United States v. Appalachian Elec. Power Co., 311 U. S. 377
20 SACKETT v. EPA

THOMAS, J., concurring

United States” does not mean any water in the United
States.
There would be little need to explain any of this if the
agencies had not effectively flouted our decision in
SWANCC, which restored navigability as the touchstone of
federal jurisdiction under the CWA, and rejected the key
arguments supporting an expansive interpretation of the
CWA’s text. We expressly held that Congress’ “use of the
phrase ‘waters of the United States’ ” in the CWA is not “a
basis for reading the term ‘navigable waters’ out of the stat-
ute”—directly contradicting the EPA’s 1973 interpretation,
upon which every subsequent expansion of its authority has
been based. 531 U. S., at 172. We also held that the Corps
did not “mist[ake] Congress’ intent” when it promulgated
its 1974 regulations, under which “ ‘the determinative fac-
tor’ ” for navigability was a “ ‘water body’s capability of use
by the public for purposes of transportation or commerce.’ ”
Id., at 168 (quoting 33 CFR §209.260(e)(1)). In doing so, we
rejected reliance on the CWA’s “ambiguous” legislative his-
tory, which the EPA had used “to expand the definition of
‘navigable waters’ ” to the outer limit of the commerce au-
thority as interpreted in the New Deal. 531 U. S., at 168,
n. 3.8 Instead, we made clear that Congress did not intend
——————
(1940), that Congress can regulate things in navigable waters for pur-
poses other than removing obstructions to navigable capacity. I note,
however, that before the New Deal era, courts consistently construed
statutes to authorize only federal actions preserving navigable capacity
in order to avoid exceeding Congress’ navigation authority. See supra,
at 8–13.
8 The historical context demonstrates that it was the Corps’ failure to

regulate to the full extent of Congress’ navigation power, not its com-
merce power generally, that led to the enactment of the CWA. See Al-
brecht & Nickelsburg, 11047 (explaining that the CWA’s legislative his-
tory is better interpreted “as the Supreme Court in SWANCC read it, to
mean simply that Congress intended to override previous, unduly nar-
row agency interpretations to assert its broadest constitutional authority
over the traditional navigable waters”); see also S. Bodine, Examining
the Term “Waters of the United States” in Its Historical Context, C.
 Cite as: 598 U. S. ____ (2023) 21

THOMAS, J., concurring

“to exert anything more than its commerce power over nav-
igation.” Ibid.; see also id., at 173 (rejecting the Govern-
ment’s argument that the CWA invokes “Congress’ power
to regulate intrastate activities that ‘substantially affect’
interstate commerce”).
SWANCC thus interpreted the text of the CWA as imple-
menting Congress’ “traditional jurisdiction over waters
that were or had been navigable in fact or which could rea-
sonably be so made”—i.e., the expanded Daniel Ball test.
531 U. S., at 172 (citing Appalachian Elec., 311 U. S., at
407–408).9 And, consistent with the traditional link be-
tween navigability and the limits of Congress’ regulatory

——————
Boyden Gray Center for the Study of the Administrative State Policy
Brief No. 4 (2022).
9 Section 404(g), added by the 1977 CWA Amendments, does not

demonstrate that the CWA departs from traditional conceptions of navi-
gability. That provision states that States may administer permit pro-
grams for discharges into “navigable waters (other than those waters
which are presently used, or are susceptible to use in their natural con-
dition or by reasonable improvement as a means to transport interstate
or foreign commerce . . . , including wetlands adjacent thereto).” 91 Stat.
1601 (codified, as amended, at 33 U. S. C. §1344(g)). This provision thus
authorizes States to establish their own permit programs over a discrete
class of traditionally navigable waters of the United States: those that
once were navigable waters of the United States, but are no longer nav-
igable in fact. See Economy Light & Power Co., 256 U. S., at 123–124.
Some have asserted that this nonjurisdictional provision—the function
of which in the statute is to expand state authority—signals that Con-
gress actually intended an unprecedented expansion of federal authority
over the States. Rapanos v. United States, 547 U. S. 715, 805–806 (2006)
(Stevens, J., dissenting); see also post, at 3–5 (KAVANAUGH, J., concurring
in judgment); post, at 1–3 (KAGAN, J., concurring in judgment). But, as
the Court explains, not only is §404(g) not the relevant definitional pro-
vision, its reference to “wetlands” is perfectly consistent with the com-
monsense recognition that some wetlands are indistinguishable from
navigable waters with which they have continuous surface connections.
Ante, at 18–22, 27. To infer Congress’ intent to upend over a century of
settled understanding and effect an unprecedented transfer of authority
over land and water to the Federal Government, based on nothing more
22 SACKETT v. EPA

THOMAS, J., concurring

authority, SWANCC noted that any broader interpretation
would raise “significant constitutional and federalism ques-
tions” and “result in a significant impingement of the
States’ traditional and primary authority over land and wa-
ter use.” 531 U. S., at 174. Both in its holdings and in its
mode of analysis, SWANCC cannot be reconciled with the
agencies’ sharp departure from the centuries-old under-
standing of navigability and the traditional limits of Con-
gress’ channels-of-commerce authority.
In sum, the plain text of the CWA and our opinion in
SWANCC demonstrate that the CWA must be interpreted
in light of Congress’ traditional authority over navigable
waters. See Albrecht & Nickelsburg 11055 (noting that
SWANCC “states more than once that Congress’ use of the
term ‘navigable waters’ signifies that Congress intended to
exercise its traditional authority over navigable waters,
and not its broader power over all things that substantially
affect commerce”). Yet, for decades, the EPA (of its own li-
cense) and the Corps (under the compulsion of an unrea-
soned and since discredited District Court order) have is-
sued substantively identical regulatory definitions of “the
waters of the United States” that completely ignore naviga-
bility and instead expand the CWA’s coverage to the outer
limits of the Court’s New Deal-era Commerce Clause prec-
edents.
III
This case demonstrates the unbounded breadth of the ju-
risdiction that the EPA and the Corps have asserted under
the CWA. The regulatory definition applied to the Sacketts’
property declares “intrastate” waters, wetlands, and vari-
ous other wet things to be “waters of the United States” if
their “use, degradation or destruction . . . could affect inter-

——————
than a negative inference from a parenthetical in a subsection that pre-
serves state authority, is counterintuitive to say the least.
 Cite as: 598 U. S. ____ (2023) 23

THOMAS, J., concurring

state or foreign commerce.” 40 CFR §230.3(s)(3) (2008) (em-
phasis added). To leave no doubt that the agencies have
entirely broken from traditional navigable waters, they give
several examples of qualifying waters: those that “are or
could be used by interstate or foreign travelers for recrea-
tional or other purposes,” those “[f]rom which fish or shell-
fish are or could be taken and sold in interstate or foreign
commerce,” those that “are used or could be used for indus-
trial purposes by industries in interstate commerce,”
“[t]ributaries of ” any such waters, and “[w]etlands adjacent
to” any such waters. §§230.3(s)(3)(i)–(iii), (5), (7). This def-
inition and others like it are premised on the fallacy repu-
diated in SWANCC: that the text of the CWA expands fed-
eral jurisdiction beyond Congress’ traditional “commerce
power over navigation.” 531 U. S., at 168, n. 3.
Nonetheless, under these boundless standards, the agen-
cies have “asserted jurisdiction over virtually any parcel of
land containing a channel or conduit . . . through which
rainwater or drainage may occasionally or intermittently
flow,” including “storm drains, roadside ditches, ripples of
sand in the desert that may contain water once a year, and
lands that are covered by floodwaters once every 100 years.”
Rapanos, 547 U. S., at 722 (plurality opinion). The agen-
cies’ definition “engulf[s] entire cities and immense arid
wastelands” alike. Ibid. Indeed, because “the entire land
area of the United States lies in some drainage basin, and
an endless network of visible channels furrows the entire
surface,” “any plot of land containing such a channel may
potentially be regulated.” Ibid.
If this interpretation were correct, the only prudent move
for any landowner in America would be to ask the Federal
Government for permission before undertaking any kind of
development. See Tr. of Oral Arg. 86, 116–117. This regime
turns Congress’ traditionally limited navigation authority
on its head. The baseline under the Constitution, the CWA,
and the Court’s precedents is state control of waters. See
24 SACKETT v. EPA

THOMAS, J., concurring

SWANCC, 531 U. S., at 174 (reaffirming “the States’ tradi-
tional and primary power over land and water use”); Leovy,
177 U. S., at 633 (repudiating an interpretation of the 1899
Act that would render practically every “creek or stream in
the entire country” a “navigable water of the United States”
and “subject the officers and agents of a State . . . to fine
and imprisonment” for draining a swamp “unless permis-
sion [was] first obtained from the Secretary of War”). By
contrast, the agencies’ interpretation amounts to a federal
police power, exercised in the most aggressive possible way.
Thankfully, applying well-established navigability rules
makes this a straightforward case. The “wetlands” on the
Sacketts’ property are not “waters of the United States” for
several independently sufficient reasons. First, for the rea-
sons set out by the Court, the Sacketts’ wetlands are not
“waters” because they lack a continuous surface connection
with a traditional navigable water. See ante, at 27. Second,
the nonnavigable so-called “tributary” (really, a roadside
ditch) across the street from the Sacketts’ property is not a
water of the United States because it is not, has never been,
and cannot reasonably be made a highway of interstate or
foreign commerce. See SWANCC, 531 U. S., at 172. Third,
the agencies have not attempted to establish that Priest
Lake is a navigable water under the expanded Daniel Ball
test. The lake is purely intrastate, and the agencies have
not shown that it is a highway of interstate or foreign com-
merce. Instead, the agencies rely primarily upon interstate
tourism and the lake’s attenuated connection to navigable
waters. See U. S. Army Corps of Engineers, G. Rayner,
Priest Lake Jurisdictional Determination (Feb. 27, 2007);
see also Brief for National Association of Home Builders of
the United States as Amicus Curiae 21–24. But, this is
likely insufficient under the traditional navigability tests to
which the CWA pegs jurisdiction. See supra, at 10–13; ac-
cord, Tr. of Oral Arg. 119 (EPA counsel conceding that Con-
gress “hasn’t used its full Commerce Clause authority” in
 Cite as: 598 U. S. ____ (2023) 25

THOMAS, J., concurring

the CWA). Finally, even assuming that a navigable water
is involved, the agencies have not established that the Sack-
etts’ actions would obstruct or otherwise impede navigable
capacity or the suitability of the water for interstate com-
merce. See Rio Grande Dam & Irrigation Co., 174 U. S., at
709.
This is not to say that determining whether a water qual-
ifies under the CWA is always easy. But, it is vital that we
ask the right question in determining what constitutes “the
waters of the United States”: whether the water is within
Congress’ traditional authority over the interstate channels
of commerce. Here, no elaborate analysis is required to
know that the Sacketts’ land is not a water, much less a
water of the United States.
IV
What happened to the CWA is indicative of deeper prob-
lems with the Court’s Commerce Clause jurisprudence.
The eclipse of Congress’ well-defined authority over the
channels of interstate commerce tracks the Court’s expan-
sion of Congress’ power “[t]o regulate Commerce with for-
eign Nations, and among the several States, and with the
Indian Tribes.” Art. I, §8, cl. 3. As I have explained at
length, the Court’s Commerce Clause jurisprudence has
significantly departed from the original meaning of the
Constitution. See Gonzales v. Raich, 545 U. S. 1, 58–59
(2005) (dissenting opinion); Lopez, 514 U. S., at 586–602
(concurring opinion). “The Clause’s text, structure, and his-
tory all indicate that, at the time of the founding, the term
‘ “commerce” consisted of selling, buying, and bartering, as
well as transporting for these purposes.’ ” Raich, 545 U. S.,
at 58. This meaning “stood in contrast to productive activ-
ities like manufacturing and agriculture,” and founding era
sources demonstrate that “the term ‘commerce’ [was] con-
sistently used to mean trade or exchange—not all economi-
cally gainful activity that has some attenuated connection
26 SACKETT v. EPA

THOMAS, J., concurring

to trade or exchange.” Ibid. (citing Lopez, 514 U. S., at 586–
587 (THOMAS, J., concurring); Barnett 112–125).10 By de-
parting from this limited meaning, the Court’s cases have
licensed federal regulatory schemes that would have been
“unthinkable” to the Constitution’s Framers and ratifiers.
Raich, 545 U. S., at 59 (opinion of THOMAS, J.).
Perhaps nowhere is this deviation more evident than in
federal environmental law, much of which is uniquely de-
pendent upon an expansive interpretation of the Commerce
Clause. See Hodel v. Virginia Surface Mining & Reclama-
tion Assn., Inc., 452 U. S. 264, 281–283 (1981); see also Brief
for Claremont Institute’s Center for Constitutional Juris-
prudence as Amicus Curiae 17–25. And many environmen-
tal regulatory schemes seem to push even the limits of the
Court’s New Deal era Commerce Clause precedents, see Ho-
del, 452 U. S., at 309–313 (Rehnquist, J., concurring in
judgment), to say nothing of the Court’s more recent prece-
dents reining in the commerce power. See, e.g., SWANCC,
531 U. S., at 173–174; cf. Rancho Viejo, LLC v. Norton, 334
F. 3d 1158, 1160 (CADC 2003) (Roberts, J., dissenting from
denial of rehearing en banc) (“The panel’s approach in this
case leads to the result that regulating the taking [under
the Endangered Species Act] of a hapless toad that, for rea-
sons of its own, lives its entire life in California constitutes
regulating ‘Commerce among the several States’ ” (ellipsis
omitted)).
——————
10 Further scholarship notes that the term “commerce” as originally

understood “was bound tightly with the Lex Mercatoria and the sort of
activities engaged in by merchants: buying and selling products made by
others (and sometimes land), associated finance and financial instru-
ments, navigation and other carriage, and intercourse across jurisdic-
tional lines.” R. Natelson, The Legal Meaning of “Commerce” in the
Commerce Clause, 80 St. John’s L. Rev. 789, 845 (2006). This “did not
include agriculture, manufacturing, mining, malum in se crime, or land
use. Nor did it include activities that merely ‘substantially affected’ com-
merce; on the contrary, the cases included wording explicitly distinguish-
ing such activities from commerce.” Ibid.
 Cite as: 598 U. S. ____ (2023) 27

THOMAS, J., concurring

The Court’s opinion today curbs a serious expansion of
federal authority that has simultaneously degraded States’
authority and diverted the Federal Government from its
important role as guarantor of the Nation’s great commer-
cial water highways into something resembling “a local zon-
ing board.” Rapanos, 547 U. S., at 738 (plurality opinion).
But, wetlands are just the beginning of the problems raised
by the agencies’ assertion of jurisdiction in this case. De-
spite our clear guidance in SWANCC that the CWA extends
only to the limits of Congress’ traditional jurisdiction over
navigable waters, the EPA and the Corps have continued to
treat the statute as if it were based on New Deal era con-
ceptions of Congress’ commerce power. But, while not all
environmental statutes are so textually limited, Congress
chose to tether federal jurisdiction under the CWA to its
traditional authority over navigable waters. The EPA and
the Corps must respect that decision.
 Cite as: 598 U. S. ____ (2023) 1

KAGAN, J., concurring in judgment

SUPREME COURT OF THE UNITED STATES
_________________

No. 21–454
_________________

MICHAEL SACKETT, ET UX., PETITIONERS v.
ENVIRONMENTAL PROTECTION
AGENCY, ET AL.
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE NINTH CIRCUIT
[May 25, 2023]

JUSTICE KAGAN, with whom JUSTICE SOTOMAYOR and
JUSTICE JACKSON join, concurring in the judgment.
Like JUSTICE KAVANAUGH, “I would stick to the text.”
Post, at 14 (opinion concurring in judgment). As he explains
in the principal concurrence, our normal method of constru-
ing statutes identifies which wetlands the Clean Water Act
covers—and the answer provided exceeds what the Court
says today. Because the Act covers “the waters of the
United States,” and those waters “includ[e]” all wetlands
“adjacent” to other covered waters, the Act extends to those
“adjacent” wetlands. 33 U. S. C. §§1362(7), 1344(g)(1). And
in ordinary language, one thing is adjacent to another not
only when it is touching, but also when it is nearby. See
post, at 4–5 (quoting multiple dictionaries). So, for exam-
ple, one house is adjacent to another even when a stretch of
grass and a picket fence separate the two. As applied here,
that means—as the EPA and Army Corps have recognized
for almost half a century—that a wetland comes within the
Act if (i) it is “contiguous to or bordering a covered water, or
(ii) if [it] is separated from a covered water only by a man-
made dike or barrier, natural river berm, beach dune, or the
like.” Post, at 14 (emphasis in original). In excluding all
the wetlands in category (ii), the majority’s “ ‘continuous
surface connection’ test disregards the ordinary meaning of
2 SACKETT v. EPA

KAGAN, J., concurring in judgment

‘adjacent.’ ” Post, at 9. The majority thus alters—more pre-
cisely, narrows the scope of—the statute Congress drafted.
And make no mistake: Congress wrote the statute it
meant to. The Clean Water Act was a landmark piece of
environmental legislation, designed to address a problem of
“crisis proportions.” R. Adler, J. Landman, & D. Cameron,
The Clean Water Act: 20 Years Later 5 (1993). How bad
was water pollution in 1972, when the Act passed? Just a
few years earlier, Ohio’s Cuyahoga River had “burst into
flames, fueled by oil and other industrial wastes.” Ibid.
And that was merely one of many alarms. Rivers, lakes,
and creeks across the country were unfit for swimming.
Drinking water was full of hazardous chemicals. Fish were
dying in record numbers (over 40 million in 1969); and those
caught were often too contaminated to eat (with mercury
and DDT far above safe levels). See id., at 5–6. So Congress
embarked on what this Court once understood as a “total
restructuring and complete rewriting” of existing water pol-
lution law. Milwaukee v. Illinois, 451 U. S. 304, 317 (1981)
(internal quotation marks omitted). The new Act estab-
lished “a self-consciously comprehensive” and “all-
encompassing program of water pollution regulation.” Id.,
at 318–319. Or said a bit differently, the Act created a pro-
gram broad enough to achieve the codified objective of “res-
tor[ing] and maintain[ing] the chemical, physical, and bio-
logical integrity of the Nation’s waters.” §1251(a). If you’ve
lately swum in a lake, happily drunk a glass of water
straight from the tap, or sat down to a good fish dinner, you
can appreciate what the law has accomplished.
Vital to the Clean Water Act’s project is the protection of
wetlands—both those contiguous to covered waters and
others nearby. As this Court (again, formerly) recognized,
wetlands “serve to filter and purify water draining into ad-
jacent bodies of water, and to slow the flow of surface runoff
into lakes, rivers, and streams.” United States v. Riverside
Bayview Homes, Inc., 474 U. S. 121, 134 (1985) (citation
 Cite as: 598 U. S. ____ (2023) 3

KAGAN, J., concurring in judgment

omitted). Wetlands thus “function as integral parts of the
aquatic environment”—protecting neighboring water if
themselves healthy, imperiling neighboring water if in-
stead degraded. Id., at 135. At the same time, wetlands
play a crucial part in flood control (if anything, more needed
now than when the statute was enacted). And wetlands
perform those functions, as JUSTICE KAVANAUGH explains,
not only when they are touching a covered water but also
when they are separated from it by a natural or artificial
barrier—say, a berm or dune or dike or levee. See post, at
12–13 (giving examples). Those barriers, as he says, “do not
block all water flow,” and in fact are usually evidence of a
significant connection between the wetland and the water.
Ibid. Small wonder, then, that the Act—as written, rather
than as read today—covers wetlands with that kind of con-
nection. Congress chose just the word needed to meet the
Act’s objective. A wetland is protected when it is “adjacent”
to a covered water—not merely when it is “adjoining” or
“contiguous” or “touching,” or (in the majority’s favorite
made-up locution) has a “continuous surface connection.”
See, e.g., ante, at 27.
Today’s majority, though, believes Congress went too far.
In the majority’s view, the Act imposes unjustifiably “crush-
ing consequences” for violations of its terms. Ante, at 3.
And many of those violations, it thinks, are of no real con-
cern, arising from “mundane” land-use conduct “like mov-
ing dirt.” Ante, at 13. Congress, the majority scolds, has
unleashed the EPA to regulate “swimming pools[ ] and pud-
dles,” wreaking untold havoc on “a staggering array of land-
owners.” Ante, at 1, 13. Surely something has to be done;
and who else to do it but this Court? It must rescue prop-
erty owners from Congress’s too-ambitious program of pol-
lution control.
So the majority shelves the usual rules of interpreta-
tion—reading the text, determining what the words used
there mean, and applying that ordinary understanding
4 SACKETT v. EPA

KAGAN, J., concurring in judgment

even if it conflicts with judges’ policy preferences. The ma-
jority’s first pass through the statute is, as JUSTICE
KAVANAUGH says, “unorthodox.” Post, at 9. “A minus B,
which includes C”? Ante, at 19. The majority could use
every letter of the alphabet, and graduate to quadratic
equations, and still not solve its essential problem. As the
majority concedes, the statute “tells us that at least some
wetlands must qualify as ‘waters of the United States.’ ”
Ante, at 18–19. More, the statute tells us what those “some
wetlands” are: the “adjacent” ones. And again, as JUSTICE
KAVANAUGH shows, “adjacent” does not mean adjoining.
See post, at 4–6; supra, at 1–2. So the majority proceeds to
its back-up plan. It relies as well on a judicially manufac-
tured clear-statement rule. When Congress (so says the
majority) exercises power “over private property”—particu-
larly, over “land and water use”—it must adopt “exceed-
ingly clear language.” Ante, at 23 (internal quotation
marks omitted). There is, in other words, a thumb on the
scale for property owners—no matter that the Act (i.e., the
one Congress enacted) is all about stopping property own-
ers from polluting. See supra, at 2.
Even assuming that thumb’s existence, the majority still
would be wrong. As JUSTICE KAVANAUGH notes, clear-
statement rules operate (when they operate) to resolve
problems of ambiguity and vagueness. See post, at 11; see
also Bond v. United States, 572 U. S. 844, 859 (2014);
United States v. Bass, 404 U. S. 336, 347 (1971). And no
such problems are evident here. One last time: “Adjacent”
means neighboring, whether or not touching; so, for exam-
ple, a wetland is adjacent to water on the other side of a
sand dune. That congressional judgment is as clear as clear
can be—which is to say, as clear as language gets. And so
a clear-statement rule must leave it alone. The majority
concludes otherwise because it is using its thumb not to re-
solve ambiguity or clarify vagueness, but instead to “cor-
rect” breadth. Those paying attention have seen this move
 Cite as: 598 U. S. ____ (2023) 5

KAGAN, J., concurring in judgment

before—actually, just last Term. In another case of envi-
ronmental regulation (involving clean air), the Court in-
voked another clear-statement rule (the so-called major
questions doctrine) to diminish another plainly expansive
term (“system of emission reduction”). See West Virginia v.
EPA, 597 U. S. ___, ___, ___ (2022) (slip op., at 2, 19).
“[C]ontra the majority,” I said then, “a broad term is not the
same thing as a ‘vague’ one.” Id., at ___ (dissenting opinion)
(slip op., at 8). And a court must treat the two differently.
A court may, on occasion, apply a clear-statement rule to
deal with statutory vagueness or ambiguity. But a court
may not rewrite Congress’s plain instructions because they
go further than preferred. That is what the majority does
today in finding that the Clean Water Act excludes many
wetlands (clearly) “adjacent” to covered waters.
And still more fundamentally, why ever have a thumb on
the scale against the Clean Water Act’s protections? The
majority first invokes federalism. See ante, at 23–24. But
as JUSTICE KAVANAUGH observes, “the Federal Govern-
ment has long regulated the waters of the United States,
including adjacent wetlands.” Post, at 11. The majority
next raises the specter of criminal penalties for “indetermi-
nate” conduct. See ante, at 24–25. But there is no peculiar
indeterminacy in saying—as regulators have said for nearly
a half century—that a wetland is covered both when it
touches a covered water and when it is separated by only a
dike, berm, dune, or similar barrier. (That standard is in
fact more definite than a host of criminal laws I could
name.) Today’s pop-up clear-statement rule is explicable
only as a reflexive response to Congress’s enactment of an
ambitious scheme of environmental regulation. It is an ef-
fort to cabin the anti-pollution actions Congress thought ap-
propriate. See ante, at 23 (complaining about Congress’s
protection of “vast” and “staggering” “additional area”).
And that, too, recalls last Term, when I remarked on special
canons “magically appearing as get-out-of-text-free cards”
6 SACKETT v. EPA

KAGAN, J., concurring in judgment

to stop the EPA from taking the measures Congress told it
to. See West Virginia, 597 U. S., at ___–___ (dissenting
opinion) (slip op., at 28–29). There, the majority’s non-tex-
tualism barred the EPA from addressing climate change by
curbing power plant emissions in the most effective way.
Here, that method prevents the EPA from keeping our
country’s waters clean by regulating adjacent wetlands.
The vice in both instances is the same: the Court’s appoint-
ment of itself as the national decision-maker on environ-
mental policy.
So I’ll conclude, sadly, by repeating what I wrote last
year, with the replacement of only a single word. “[T]he
Court substitutes its own ideas about policymaking for Con-
gress’s. The Court will not allow the Clean [Water] Act to
work as Congress instructed. The Court, rather than Con-
gress, will decide how much regulation is too much.” Id., at
___ (slip op., at 32). Because that is not how I think our
Government should work—more, because it is not how the
Constitution thinks our Government should work—I re-
spectfully concur in the judgment only.
 Cite as: 598 U. S. ____ (2023) 1

KAVANAUGH, J., concurring in judgment

SUPREME COURT OF THE UNITED STATES
_________________

No. 21–454
_________________

MICHAEL SACKETT, ET UX., PETITIONERS v.
ENVIRONMENTAL PROTECTION
AGENCY, ET AL.
ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
APPEALS FOR THE NINTH CIRCUIT
[May 25, 2023]

JUSTICE KAVANAUGH, with whom JUSTICE SOTOMAYOR,
JUSTICE KAGAN, and JUSTICE JACKSON join, concurring in
the judgment.
The Clean Water Act generally prohibits dumping
dredged or fill material without a permit into the “waters of
the United States.” 33 U. S. C. §§1311(a), 1344(a), 1362.
The “waters of the United States” include wetlands that are
“adjacent” to waters covered by the Act—for example,
wetlands that are adjacent to covered rivers or lakes.
§§1344(g), 1362(7). The question in this case is whether the
wetlands on the Sacketts’ residential property are adjacent
to covered waters and therefore covered under the Act.
The Ninth Circuit held that the wetlands on the Sacketts’
property are covered by the Clean Water Act because, as
relevant here, the wetlands have a “significant nexus” to
covered waters nearby. 8 F. 4th 1075, 1093 (2021). The
Court today reverses the Ninth Circuit’s judgment.
I agree with the Court’s reversal of the Ninth Circuit. In
particular, I agree with the Court’s decision not to adopt the
“significant nexus” test for determining whether a wetland
is covered under the Act. And I agree with the Court’s
bottom-line judgment that the wetlands on the Sacketts’
2 SACKETT v. EPA

KAVANAUGH, J., concurring in judgment

property are not covered by the Act and are therefore not
subject to permitting requirements.
I write separately because I respectfully disagree with
the Court’s new test for assessing when wetlands are
covered by the Clean Water Act. The Court concludes that
wetlands are covered by the Act only when the wetlands
have a “continuous surface connection” to waters of the
United States—that is, when the wetlands are “adjoining”
covered waters. Ante, at 20, 22 (internal quotation marks
omitted). In my view, the Court’s “continuous surface
connection” test departs from the statutory text, from 45
years of consistent agency practice, and from this Court’s
precedents. The Court’s test narrows the Clean Water Act’s
coverage of “adjacent” wetlands to mean only “adjoining”
wetlands. But “adjacent” and “adjoining” have distinct
meanings: Adjoining wetlands are contiguous to or
bordering a covered water, whereas adjacent wetlands
include both (i) those wetlands contiguous to or bordering a
covered water, and (ii) wetlands separated from a covered
water only by a man-made dike or barrier, natural river
berm, beach dune, or the like. By narrowing the Act’s
coverage of wetlands to only adjoining wetlands, the Court’s
new test will leave some long-regulated adjacent wetlands
no longer covered by the Clean Water Act, with significant
repercussions for water quality and flood control
throughout the United States. Therefore, I respectfully
concur only in the Court’s judgment.
I
The Clean Water Act generally prohibits dumping a
“pollutant”—including dredged or fill material—into
“navigable waters” without a permit. 33 U. S. C. §§1311(a),
1344(a), 1362. The Act defines “navigable waters” as “the
waters of the United States, including the territorial seas.”
§1362(7).
As the Court today ultimately agrees, see ante, at 19, and
 Cite as: 598 U. S. ____ (2023) 3

KAVANAUGH, J., concurring in judgment

the Sacketts acknowledge, see Tr. of Oral Arg. 7–8, 33–34,
56–57, the statutory term “waters of the United States”
covers wetlands “adjacent” to waters of the United States—
for example, wetlands adjacent to a river or lake that is
itself a water of the United States. 33 U. S. C. §1344(g).
As enacted in 1972, the Clean Water Act protected “the
waters of the United States.” §§1311(a), 1362(7), 1362(12).
In 1975, the Army Corps interpreted “waters of the United
States” to include wetlands “adjacent to other navigable
waters.” 40 Fed. Reg. 31324. In 1977, Congress expressly
adopted that same understanding of the Act, amending the
Act to make clear that only the Federal Government, and
not the States, may issue Clean Water Act permits for
dumping dredged or fill material into certain “waters of the
United States,” “including wetlands adjacent” to those
covered waters. Clean Water Act, 91 Stat. 1601; 33 U. S. C.
§1344(g). In that 1977 Act, Congress thus expressly
recognized “adjacent wetlands” as “waters of the United
States.”
Interpreting the text of the Act as amended in 1977, this
Court has long held that the Act covers “adjacent” wetlands.
See United States v. Riverside Bayview Homes, Inc., 474
U. S. 121, 134–135, 138 (1985) (“Congress expressly stated
that the term ‘waters’ included adjacent wetlands.”); see
also Rapanos v. United States, 547 U. S. 715, 742 (2006)
(plurality opinion) (wetlands that “are ‘adjacent to’ ” waters
of the United States are “covered by the Act”); Solid Waste
Agency of Northern Cook Cty. v. Army Corps of Engineers,
531 U. S. 159, 167, 172 (2001) (recognizing “Congress’
unequivocal” “approval of, the Corps’ regulations
interpreting the [Act] to cover wetlands adjacent to
navigable waters”). The Court has also ruled that the Act’s
coverage of adjacent wetlands does not extend to “isolated”
wetlands. Id., at 168–172.
So the question here becomes the meaning of “adjacent”
wetlands under the Clean Water Act. As a matter of
4 SACKETT v. EPA

KAVANAUGH, J., concurring in judgment

ordinary meaning and longstanding agency practice, a
wetland is “adjacent” to a covered water (i) if the wetland is
adjoining—that is, contiguous to or bordering—a covered
water—or (ii) if the wetland is separated from a covered
water only by a man-made dike or barrier, natural river
berm, beach dune, or the like.
The Court and I agree that wetlands in the first
category—that is, wetlands adjoining a covered water—are
covered as adjacent wetlands. Ante, at 19–22. But the
Court and I disagree about the second category—that is,
wetlands separated from a covered water only by a man-
made dike or barrier, natural river berm, beach dune, or the
like. The Court concludes that wetlands in that second
category are not covered as adjacent wetlands because
those wetlands do not have a continuous surface connection
to a covered water—in other words, those wetlands are not
adjoining the covered water. I disagree because the
statutory text (“adjacent”) does not require a continuous
surface connection between those wetlands and covered
waters.
The ordinary meaning of the term “adjacent” has not
changed since Congress amended the Clean Water Act in
1977 to expressly cover “wetlands adjacent” to waters of the
United States. 91 Stat. 1601; 33 U. S. C. §1344(g). Then as
now, “adjacent” means lying near or close to, neighboring,
or not widely separated. Indeed, the definitions of
“adjacent” are notably explicit that two things need not
touch each other in order to be adjacent. “Adjacent”
includes “adjoining” but is not limited to “adjoining.” See,
e.g., Black’s Law Dictionary 62 (rev. 4th ed. 1968) (defining
“adjacent” as “Lying near or close to; sometimes,
contiguous; neighboring; . . . may not actually touch”);
Black’s Law Dictionary 50 (11th ed. 2019) (defining
“adjacent” as “Lying near or close to, but not necessarily
touching”); see also, e.g., Webster’s Third New
International Dictionary 26 (1976) (defining “adjacent” as
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KAVANAUGH, J., concurring in judgment

“to lie near, border on”; “not distant or far off ”; “nearby but
not touching”).
By contrast to the Clean Water Act’s express inclusion of
“adjacent” wetlands, other provisions of the Act use the
narrower term “adjoining.” Compare 33 U. S. C. §1344(g)
with §§1321(b)–(c) (“adjoining shorelines” and “adjoining
shorelines to the navigable waters”); §1346(c) (“land
adjoining the coastal recreation waters”); see also
§1254(n)(4) (“estuary” includes certain bodies of water
“having unimpaired natural connection with open sea”);
§2802(5) (“ ‘coastal waters’ ” includes wetlands “having
unimpaired connection with the open sea up to the head of
tidal influence”). The difference in those two terms is
critical to this case. Two objects are “adjoining” if they “are
so joined or united to each other that no third object
intervenes.” 1968 Black’s 62 (comparing “adjacent” with
“adjoining”); see ibid. (“Adjoining” means “touching or
contiguous, as distinguished from lying near to or
adjacent”); see also Black’s Law Dictionary 38–39 (5th ed.
1979) (same); Webster’s Third 26–27 (similar). As applied
to wetlands, a marsh is adjacent to a river even if separated
by a levee, just as your neighbor’s house is adjacent to your
house even if separated by a fence or an alley.
In other contexts, this Court has recognized the
important difference in the meaning of the terms “adjacent”
and “adjoining” and has held that “adjacent” is broader
than “adjoining or actually contiguous.” United States v.
St. Anthony R. Co., 192 U. S. 524, 533 (1904). As an
example, the St. Anthony case concerned a federal statute
granting railroads the right to cut timber from “public lands
adjacent” to a railroad right of way. Id., at 526, n. 1, 530.
The Court held that timber could be taken from “adjacent”
sections of land that were not “contiguous to or actually
touching” the right of way. Id., at 538. The Court explained
that if “the word ‘adjoining’ had been used instead of
‘adjacent,’ ” a railroad could not have taken the relevant
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KAVANAUGH, J., concurring in judgment

timber. Ibid.
In short, the term “adjacent” is broader than “adjoining”
and does not require that two objects actually touch. We
must presume that Congress used the term “adjacent”
wetlands in 1977 to convey a different meaning than
“adjoining” wetlands. See Russello v. United States, 464
U. S. 16, 23 (1983).
II
Longstanding agency practice reinforces the ordinary
meaning of adjacency and demonstrates, contrary to the
Court’s conclusion today, that the term “adjacent” is
broader than “adjoining.”
After the Act was passed in 1972, a key question quickly
arose: Did “waters of the United States” include wetlands?
By 1975, the Army Corps concluded that the term “waters
of the United States” included “adjacent” wetlands. 40 Fed.
Reg. 31324. In 1977, Congress itself made clear that
“adjacent” wetlands were covered by the Act by amending
the Act and enacting §1344(g). 91 Stat. 1601.
Since 1977, when Congress explicitly included “adjacent”
wetlands within the Act’s coverage, the Army Corps has
adopted a variety of interpretations of its authority over
those wetlands—some more expansive and others less
expansive. But throughout those 45 years and across all
eight Presidential administrations, the Army Corps has
always included in the definition of “adjacent wetlands” not
only wetlands adjoining covered waters but also those
wetlands that are separated from covered waters by a man-
made dike or barrier, natural river berm, beach dune, or the
like.
 In 1977 and 1980, under President Carter, the Army
Corps and EPA defined “adjacent” wetlands as
including wetlands “separated from other waters of the
United States by man-made dikes or barriers, natural
river berms, beach dunes and the like.” 42 Fed. Reg.
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KAVANAUGH, J., concurring in judgment

37144; see 45 Fed. Reg. 85345.
 In 1986, under President Reagan, the Army Corps
adopted a new regulatory provision defining “waters of
the United States” and reaffirmed that “adjacent”
wetlands include wetlands “separated from other
waters of the United States by man-made dikes or
barriers, natural river berms, beach dunes and the
like.” 51 Fed. Reg. 41210, 41251.
 From 1986 until 2015, under Presidents Reagan,
George H. W. Bush, Clinton, George W. Bush, and
Obama, the regulations continued to cover wetlands
“separated from other waters of the United States by
man-made dikes or barriers, natural river berms,
beach dunes and the like.” See 33 CFR §328.3(c)
(1991); 40 CFR §230.3(b) (1991); 33 CFR §328.3(c)
(1998); 40 CFR §230.3(b) (1998); 33 CFR §328.3(c)
(2005); 40 CFR §230.3(b) (2005); 33 CFR §328.3(c)
(2010); 40 CFR §230.3(b) (2010).
 In 2015, under President Obama, the Army Corps and
EPA promulgated a new rule, which again specified
that “adjacent” wetlands include wetlands “separated
by constructed dikes or barriers, natural river berms,
beach dunes, and the like.” 80 Fed. Reg. 37105, 37116.
 In 2019 and 2020, under President Trump, the Army
Corps and EPA repealed the 2015 rule and issued a
new rule. But even following the repeal and new rule,
adjacent wetlands included wetlands that are
“physically separated” from certain covered waters
“only by a natural berm, bank, dune, or similar natural
feature” or “only by an artificial dike, barrier, or similar
artificial structure so long as that structure allows for
a direct hydrologic surface connection . . . in a typical
year, such as through a culvert, flood or tide gate,
pump, or similar artificial feature.” 85 Fed. Reg. 22338,
22340 (2020).
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 In 2023, under President Biden, the Army Corps and
EPA once again issued a new rule that defined
“adjacent” wetlands to include wetlands “separated
from other waters of the United States by man-made
dikes or barriers, natural river berms, beach dunes,
and the like.” 88 Fed. Reg. 3143–3144.
That longstanding and consistent agency interpretation
reflects and reinforces the ordinary meaning of the statute.
The eight administrations since 1977 have maintained
dramatically different views of how to regulate the
environment, including under the Clean Water Act. Some
of those administrations promulgated very broad
interpretations of adjacent wetlands. Others adopted far
narrower interpretations. Yet all of those eight different
administrations have recognized as a matter of law that the
Clean Water Act’s coverage of adjacent wetlands means
more than adjoining wetlands and also includes wetlands
separated from covered waters by man-made dikes or
barriers, natural river berms, beach dunes, or the like.
That consistency in interpretation is strong confirmation of
the ordinary meaning of adjacent wetlands.
III
The Act covers “adjacent” wetlands. And adjacent
wetlands is a broader category than adjoining wetlands.
But instead of adhering to the ordinary meaning of
“adjacent” wetlands, to the 45 years of consistent agency
practice, and to this Court’s precedents, the Court today
adopts a test under which a wetland is covered only if the
wetland has a “continuous surface connection” to a covered
water—in other words, if it adjoins a covered water. Ante,
at 22 (internal quotation marks omitted). The Court says
that the wetland and the covered water must be
“indistinguishable” from one another—in other words,
there must be no “clear demarcation” between wetlands and
covered waters. Ante, at 21 (internal quotation marks
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KAVANAUGH, J., concurring in judgment

omitted).
The Court’s “continuous surface connection” test
disregards the ordinary meaning of “adjacent.” The Court’s
mistake is straightforward: The Court essentially reads
“adjacent” to mean “adjoining.” As a result, the Court
excludes wetlands that the text of the Clean Water Act
covers—and that the Act since 1977 has always been
interpreted to cover.
In support of its narrower “continuous surface
connection” interpretation of covered wetlands, the Court
emphasizes that the 1972 Act’s overarching statutory term
is “waters of the United States.” Ante, at 19. And the Court
suggests that the term “waters of the United States” cannot
be interpreted to cover “adjacent wetlands” but only
“adjoining wetlands.” See ante, at 19–22. But in 1977,
Congress itself expressly made clear that the “waters of the
United States” include “adjacent” wetlands. 91 Stat. 1601.
And Congress would not have used the word “adjacent” in
1977 if Congress actually meant “adjoining,” particularly
because Congress used the word “adjoining” in several
other places in the Clean Water Act. 33 U. S. C. §§1321(b)–
(c), 1346(c); see also §§1254(n)(4), 2802(5).
To bolster its unorthodox statutory interpretation, the
Court resorts to a formula: “A minus B, which includes C.”
Ante, at 19. That just seems to be a fancier way of arguing
(against all indications of ordinary meaning) that
“adjacent” means “adjoining.” But again the Court is
imposing a restriction nowhere to be found in the text. In
the end, the Court has no good answer for why Congress
used the term “adjacent” instead of “adjoining” when
Congress enacted §1344(g) in 1977.1
——————
1 Perhaps recognizing the difficulty of reading the Act to mean

“adjoining” when it actually says “adjacent,” the Court at one point
suggests that “adjoining” is equivalent to “adjacent.” Ante, at 19–20. As
a matter of ordinary meaning, as explained at length above, that is
incorrect. Adjoining wetlands are a subset of adjacent wetlands, not the
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Recall again how the 1977 Act came about. In 1975, the
Army Corps concluded that the 1972 Act’s coverage of
“waters of the United States” included “adjacent” wetlands.
40 Fed. Reg. 31324. Then in 1977, Congress adopted a new
permitting program for a category of “waters of the United
States.” Congress allocated to the Federal Government
exclusive authority to issue Clean Water Act permits for
dumping dredged or fill material into certain “waters of the
United States,” “including wetlands adjacent thereto.” 91
Stat. 1601. Through that statutory text, Congress made
clear its understanding that “waters of the United States”
included “adjacent” wetlands—and indeed, Congress
designed important federal-state permitting authorities
around that precise understanding. Congress’s 1977
amendment did not “merely” express “an opinion” about the
meaning of the Clean Water Act; rather, it reflected what
Congress understood “its own prior acts to mean.” Bell v.
New Jersey, 461 U. S. 773, 785, n. 12 (1983) (internal
quotation marks omitted).
Moreover, Congress’s 1977 decision was no accident. As
this Court has previously recognized, “the scope of the
Corps’ asserted jurisdiction over wetlands”—including the
Corps’ decision to cover adjacent wetlands—“was
specifically brought to Congress’ attention” in 1977, “and
Congress rejected measures designed to curb the Corps’
jurisdiction.” United States v. Riverside Bayview Homes,
Inc., 474 U. S. 121, 137 (1985). Subsequently, this Court
has recognized that Congress’s 1977 amendment made
clear that the Act “cover[s] wetlands adjacent to navigable
waters.” Solid Waste Agency of Northern Cook Cty. v. Army
Corps of Engineers, 531 U. S. 159, 167 (2001); see Riverside
Bayview, 474 U. S., at 138 (“Congress expressly stated that
the term ‘waters’ included adjacent wetlands”).
Not surprisingly, in the years since 1977, no one has
——————
whole set of adjacent wetlands.
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KAVANAUGH, J., concurring in judgment

seriously disputed that the Act covers adjacent wetlands.
And in light of the text of the Act, eight consecutive
Presidential administrations have recognized that the Act
covers adjacent wetlands and that adjacent wetlands
include more than simply adjoining wetlands. The Court’s
analysis today therefore seems stuck in a bit of a time
warp—relitigating an issue that Congress settled in 1977
and that this Court has long treated as settled: The Act
covers adjacent wetlands. By adopting a test that
substitutes “adjoining” for “adjacent,” the Court today errs.
The Court also invokes federalism and vagueness
concerns. The Court suggests that ambiguities or
vagueness in federal statutes regulating private property
should be construed in favor of the property owner,
particularly given that States have traditionally regulated
private property rights. See ante, at 23–25; see also Solid
Waste Agency of Northern Cook Cty., 531 U. S., at 173–174.
To begin with, the Federal Government has long regulated
the waters of the United States, including adjacent
wetlands.
In any event, the decisive point here is that the term
“adjacent” in this statute is unambiguously broader than
the term “adjoining.” On that critical interpretive question,
there is no ambiguity. We should not create ambiguity
where none exists. And we may not rewrite “adjacent” to
mean the same thing as “adjoining,” as the Court does
today.
Finally, contrary to the Court’s suggestion otherwise, the
analysis in this separate opinion centers on the “operative”
text, “waters of the United States.” Ante, at 27. To recap:
The 1972 Act covered “waters of the United States.” In
1977, when Congress allocated permitting authority,
Congress expressly included “adjacent” wetlands within the
“waters of the United States.” Since then, the Executive
Branch and this Court have recognized that “waters of the
United States” covers “adjacent” wetlands. Based on the
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KAVANAUGH, J., concurring in judgment

text of the statute, as well as 45 years of consistent agency
practice and this Court’s precedents, I respectfully disagree
with the Court’s decision to interpret “waters of the United
States” to include only adjoining wetlands and not adjacent
wetlands.
IV
The difference between “adjacent” and “adjoining” in this
context is not merely semantic or academic. The Court’s
rewriting of “adjacent” to mean “adjoining” will matter a
great deal in the real world. In particular, the Court’s new
and overly narrow test may leave long-regulated and long-
accepted-to-be-regulable wetlands suddenly beyond the
scope of the agencies’ regulatory authority, with negative
consequences for waters of the United States. For example,
the Mississippi River features an extensive levee system to
prevent flooding. Under the Court’s “continuous surface
connection” test, the presence of those levees (the
equivalent of a dike) would seemingly preclude Clean
Water Act coverage of adjacent wetlands on the other side
of the levees, even though the adjacent wetlands are often
an important part of the flood-control project. See Brief for
Respondents 30. Likewise, federal protection of the
Chesapeake Bay might be less effective if fill can be dumped
into wetlands that are adjacent to (but not adjoining) the
bay and its covered tributaries. See id., at 35. Those are
just two of many examples of how the Court’s overly narrow
view of the Clean Water Act will have concrete impact.
As those examples reveal, there is a good reason why
Congress covered not only adjoining wetlands but also
adjacent wetlands. Because of the movement of water
between adjacent wetlands and other waters, pollutants in
wetlands often end up in adjacent rivers, lakes, and other
waters. Natural barriers such as berms and dunes do not
block all water flow and are in fact evidence of a regular
connection between a water and a wetland. 85 Fed. Reg.
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KAVANAUGH, J., concurring in judgment

22307; 88 Fed. Reg. 3095, 3118. Similarly, artificial
barriers such as dikes and levees typically do not block all
water flow, 85 Fed. Reg. 22312; 88 Fed. Reg. 3076, and
those artificial structures were often built to control the
surface water connection between the wetland and the
water. 85 Fed. Reg. 22315; 88 Fed. Reg. 3118. The
scientific evidence overwhelmingly demonstrates that
wetlands separated from covered waters by those kinds of
berms or barriers, for example, still play an important role
in protecting neighboring and downstream waters,
including by filtering pollutants, storing water, and
providing flood control. See 88 Fed. Reg. 3118; 33 CFR
§320.4(b)(2) (2022); see also United States v. Riverside
Bayview Homes, Inc., 474 U. S. 121, 134 (1985). In short,
those adjacent wetlands may affect downstream water
quality and flood control in many of the same ways that
adjoining wetlands can.
The Court’s erroneous test not only will create real-world
consequences for the waters of the United States, but also
is sufficiently novel and vague (at least as a single
standalone test) that it may create regulatory uncertainty
for the Federal Government, the States, and regulated
parties. As the Federal Government suggests, the
continuous surface connection test raises “a host of thorny
questions” and will lead to “potentially arbitrary results.”
Brief for Respondents 29. For example, how difficult does
it have to be to discern the boundary between a water and
a wetland for the wetland to be covered by the Clean Water
Act? How does that test apply to the many kinds of
wetlands that typically do not have a surface water
connection to a covered water year-round—for example,
wetlands and waters that are connected for much of the
year but not in the summer when they dry up to some
extent? How “temporary” do “interruptions in surface
connection” have to be for wetlands to still be covered?
Ante, at 21. How does the test operate in areas where
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KAVANAUGH, J., concurring in judgment

storms, floods, and erosion frequently shift or breach
natural river berms? Can a continuous surface connection
be established by a ditch, swale, pipe, or culvert? See 88
Fed. Reg. 3095. The Court covers wetlands separated from
a water by an artificial barrier constructed illegally, see
ante, at 21–22, n. 16, but why not also include barriers
authorized by the Army Corps at a time when it would not
have known that the barrier would cut off federal
authority? The list goes on.
Put simply, the Court’s atextual test—rewriting
“adjacent” to mean “adjoining”—will produce real-world
consequences for the waters of the United States and will
generate regulatory uncertainty. I would stick to the text.
There can be no debate, in my respectful view, that the key
statutory term is “adjacent” and that adjacent wetlands is
a broader category than adjoining wetlands. To be faithful
to the statutory text, we cannot interpret “adjacent”
wetlands to be the same thing as “adjoining” wetlands.
* * *
In sum, I agree with the Court’s decision not to adopt the
“significant nexus” test for adjacent wetlands. I
respectfully disagree, however, with the Court’s new
“continuous surface connection” test. In my view, the
Court’s new test is overly narrow and inconsistent with the
Act’s coverage of adjacent wetlands. The Act covers
adjacent wetlands, and a wetland is “adjacent” to a covered
water (i) if the wetland is contiguous to or bordering a
covered water, or (ii) if the wetland is separated from a
covered water only by a man-made dike or barrier, natural
river berm, beach dune, or the like. The wetlands on the
Sacketts’ property do not fall into either of those categories
and therefore are not covered under the Act as I would
interpret it. Therefore, like the Court, I would reverse the
judgment of the U. S. Court of Appeals for the Ninth Circuit
and remand for further proceedings. But I respectfully
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KAVANAUGH, J., concurring in judgment

concur only in the Court’s judgment.