Michael Sackett ; Chantell Sackett v. U.S. ENVIRONMENTAL PROTECTION AGENCY; MICHAEL S. REGAN, Administrator

FOR PUBLICATION
UNITED STATES COURT OF APPEALS
FOR THE NINTH CIRCUIT
M ICHAEL SACKETT ; CHANTELL
SACKETT ,
Plaintiffs-Appellants,
v.
U.S. ENVIRONMENTAL PROTECTION
AGENCY; M ICHAEL S. REGAN,
Administrator,*
Defendants-Appellees.
No. 19-35469
D.C. No.
2:08-cv-00185-
EJL
OPINION
Appeal from the United States District Court
for the District of Idaho
Edward J. Lodge, District Judge, Presiding
Argued and Submitted November 19, 2020
Submission Withdrawn December 1, 2020
Resubmitted August 9, 2021
Seattle, Washington
Filed August 16, 2021
* Michael S. Regan has been automatically substituted for former
Administrator Steven L. Johnson. Fed. R. App. P. 43(c)(2).

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2 SACKETT V. USEPA
Before: Ronald M. Gould and Michelle T. Friedland,
Circuit Judges, and Jill A. Otake,** District Judge.
Opinion by Judge Friedland
SUMMARY***
Mootness / Environmental Law
The panel affirmed the district court’s summary
judgment in favor of the Environmental Protection Agency
(“EPA”) in an action brought by plaintiff landowners,
challenging an EPA compliance order that stated that
plaintiffs’ property contained wetlands subject to protection
under the Clean Water Act (“CWA”) and that directed them
to remove fill and restore the property to its natural state.
When the parties were briefing this appeal, in a letter to
plaintiffs, EPA abruptly withdrew its compliance order. The
panel held that the EPA’s withdrawal of the order did not
moot this case. EPA’s stated intention not to enforce the
amended compliance order or issue a similar one in the
future did not bind the agency, and EPA could potentially
change positions under new leadership. In addition, the
letter did nothing to alter EPA’s litigation position that it has
authority to regulate the plaintiffs’ property. Accordingly,
the panel could not conclude that it was “absolutely clear”
** The Honorable Jill A. Otake, United States District Judge for the
District of Hawaii, sitting by designation.
*** This summary constitutes no part of the opinion of the court. It
has been prepared by court staff for the convenience of the reader.

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SACKETT V. USEPA 3
that EPA would not either reinstate the amended compliance
or issue a new one, and, therefore, this case was not moot.
The panel rejected EPA’s arguments to the contrary.
The panel next addressed the district court’s refusal to
strike a July 2008 Memo by EPA wetlands ecologist John
Olson from the administrative record. The Memo contained
observations and photographs from Olson’s visit to
plaintiffs’ property. The panel held, pursuant to its review
under the Administrative Procedure Act, that the district
court did not abuse its discretion in permitting EPA to
include the July 2008 Memo in the administrative record.
Turning to the entry of summary judgment on the merits,
the panel held that, under Northern California River Watch
v. City of Healdsburg, 496 F.3d 993, 999–1000 (9th Cir.
2007), Justice Kennedy’s understanding of “significant
nexus” in his concurring opinion in Rapanos v. United
States, 547 U.S. 715 (2006), provided the governing
standard for determining when wetlands are regulated under
the CWA. The panel rejected plaintiffs’ arguments that
Northern California River Watch v. City of Healdsburg was
no longer law of the circuit. Applying the significant nexus
standard, the panel held that the requirements of the
concurrence and the applicable regulations were satisfied
here. The panel concluded that EPA reasonably determined
that plaintiffs’ property contained wetlands. It further
determined that the record plainly supported EPA’s
conclusion that the wetlands on plaintiffs’ property were
adjacent to a jurisdictional tributary and that, together with a
similarly situated wetlands complex, they had a significant
nexus to Priest Lake, a traditional navigable water, such that
the property was regulable under the CWA and the relevant
regulations.

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4 SACKETT V. USEPA
COUNSEL
Anthony L. François (argued) and Damien M. Schiff, Pacific
Legal Foundation, Sacramento, California, for Plaintiffs-
Appellants.
Brian C. Toth (argued) and David Gunter, Attorneys; Eric
Grant, Deputy Assistant Attorney General; Jean E.
Williams, Acting Assistant Attorney General; Environment
and Natural Resources Division, United States Department
of Justice, Washington, D.C.; Karyn Wendelowski,
Attorney, United States Environmental Protection Agency,
Washington, D.C.; for Defendants-Appellees.
OPINION
FRIEDLAND, Circuit Judge:
Plaintiffs Chantell and Michael Sackett purchased a
soggy residential lot near Idaho’s Priest Lake in 2004. They
planned to build a home on the property, but the project
became entangled in a regulatory dispute. Shortly after the
Sacketts began placing sand and gravel fill on the lot, they
received an administrative compliance order from the
Environmental Protection Agency (“EPA”). The order
stated that the property contained wetlands subject to
protection under the Clean Water Act (“CWA”), and that the
Sacketts had to remove the fill and restore the property to its
natural state. Instead, the Sacketts sued EPA in 2008,
contending that the agency’s jurisdiction under the CWA
does not extend to their property. The case has been winding
its way through the federal courts ever since. When the
parties were briefing this appeal, EPA abruptly withdrew its
compliance order.

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SACKETT V. USEPA 5
We first consider whether EPA’s withdrawal of the
compliance order, twelve years after it first issued, moots
this case. We hold that it does not. We then decide whether
jurisdiction under the CWA extends to the Sacketts’ lot. We
hold that it does and thus affirm the district court’s grant of
summary judgment in EPA’s favor.
I.
A.
Congress enacted the CWA “to restore and maintain the
chemical, physical, and biological integrity of the Nation’s
waters.” 33 U.S.C. § 1251(a). The Act extends to all
“navigable waters,” defined as “waters of the United States,
including the territorial seas,” and it prohibits any person
who lacks a permit from discharging pollutants, including
rocks and sand, into those waters. Id. §§ 1311(a), 1362(6),
(7), (12). If EPA finds that a violation is occurring, one of
its enforcement options is to issue an administrative
compliance order—as was issued to the Sacketts. Id.
§ 1319(a). A compliance order describes the nature of the
violation and requires the recipient to cease the illegal
discharge activity. See id. To enforce a compliance order,
EPA may bring an enforcement action in federal district
court. Id. § 1319(b).
Since the CWA was enacted, agencies and courts have
struggled to identify the outer definitional limits of the
phrase “waters of the United States,” which in turn defines
the scope of the federal government’s regulatory jurisdiction
under the CWA. The U.S. Army Corps of Engineers (the
“Corps”) first issued regulations defining “waters of the
United States” in the 1970s, shortly after the CWA took
effect. Initially, the Corps determined that the CWA covered
only waters that were navigable in fact, see 39 Fed.

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6 SACKETT V. USEPA
Reg. 12,115, 12,119 (Apr. 3, 1974), but the Corps later
adopted different, broader interpretations that remained in
effect at the time the Sacketts received the compliance order,
see 42 Fed. Reg. 37,122, 37,144 (July 19, 1977); 51 Fed.
Reg. 41,206, 41,250–51 (Nov. 13, 1986); 53 Fed. Reg.
20,764, 20,774 (June 6, 1988).
As relevant here, the regulations defined “waters of the
United States” to include “wetlands” that are “adjacent” to
traditional navigable waters and their tributaries. See
33 C.F.R. § 328.3(a)(1), (a)(5), (a)(7) (2008). “Wetlands”
were defined as “areas that are inundated or saturated by
surface or ground water at a frequency and duration
sufficient to support, and that under normal circumstances
do support, a prevalence of vegetation typically adapted for
life in saturated soil conditions.” Id. § 328.3(b). “Adjacent”
was defined as “bordering, contiguous, or neighboring,” and
the regulations explicitly stated that “adjacent wetlands”
included wetlands separated from other waters of the United
States by artificial dikes or barriers. Id. § 328.3(c).1
1 In the years since the challenged compliance order issued, EPA
and the Corps have continued to revise the regulatory definition of
“waters of the United States” under the CWA. In 2015, the agencies
proposed the Clean Water Rule, 80 Fed. Reg. 37,054 (June 29, 2015).
But implementation of the Clean Water Rule was stayed pursuant to
multiple court challenges, and two courts eventually decided that the rule
was “unlawful” and remanded it to the agencies. See Georgia v.
Wheeler, 418 F. Supp. 3d 1336, 1372 (S.D. Ga. 2019); Texas v. EPA,
389 F. Supp. 3d 497, 504–06 (S.D. Tex. 2019). The agencies ultimately
repealed the Clean Water Rule and reinstated the pre-2015 regulatory
definition. See 84 Fed. Reg. 56,626, 56,659–60 (Oct. 22, 2019).
On January 23, 2020, EPA and the Corps promulgated yet another
regulatory definition of “waters of the United States.” See 85 Fed. Reg.
22,250, 22,273 (Apr. 21, 2020). The agencies, however, are currently

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SACKETT V. USEPA 7
In several decisions, the Supreme Court has grappled
with the proper interpretation of 33 U.S.C. § 1362(7)’s
phrase “the waters of the United States.” In United States v.
Riverside Bayview Homes, Inc., 474 U.S. 121 (1985), the
Court held that the Corps’ interpretation of that phrase as
including wetlands that were not themselves navigable, but
which “actually abut[ted] on” traditional navigable
waterways, was “a permissible interpretation” of the CWA.
Id. at 131–35. Then, in Solid Waste Agency of Northern
Cook County v. U.S. Army Corps of Engineers, 531 U.S. 159
(2001), the Court rejected the Corps’ attempt to regulate
isolated sand and gravel pits that “seasonally ponded,”
holding that the term “waters of the United States” does not
include “nonnavigable, isolated, intrastate waters.” Id.
at 164, 172–174.
Finally, and most relevant here, in Rapanos v. United
States, 547 U.S. 715 (2006), the Court vacated two decisions
upholding the application of the CWA to wetlands connected
to distant navigable waters via ditches or artificial drains. Id.
at 757. In his plurality opinion, Justice Scalia, joined by
three other Justices, articulated one test for determining
whether wetlands could be regulated under the CWA, id.
at 739, while Justice Kennedy authored a concurrence
articulating a different test, id. at 779–80. The parties here
reevaluating that Rule, in keeping with President Biden’s executive order
Protecting Public Health and the Environment and Restoring Science to
Tackle the Climate Crisis, Exec. Order No. 13990, 86 Fed. Reg. 7037
(Jan. 20, 2021). See Definition of “Waters of the United States”: Rule
Status and Litigation Update, U.S. EPA, https://www.epa.gov/nwpr/def
inition-waters-united-states-rule-status-and-litigation-update (last
updated Apr. 23, 2021) (“Consistent with the Executive Order, EPA and
the [Corps] are reviewing the [2020] Rule.”).

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8 SACKETT V. USEPA
dispute which Rapanos opinion controls whether EPA has
jurisdiction over the Sacketts’ lot.
B.
In 2004, the Sacketts purchased a 0.63-acre lot near
Priest Lake, one of the largest lakes in Idaho. The property
is bounded by roads to the north and south. To the north,
across Kalispell Bay Road, lies the Kalispell Bay Fen, a large
wetlands complex that drains into an unnamed tributary.
That tributary feeds Kalispell Creek, which, in turn, flows
southwest of the Sacketts’ property and then empties into
Priest Lake. To the south, across another road, is a row of
homes fronting Priest Lake. The Sacketts’ property is
300 feet from the lake.
In May 2007, having obtained building permits from
their county, the Sacketts began backfilling the property with
sand and gravel to create a stable grade. EPA and Corps
officials soon visited the property and, believing the property
contained wetlands that might be subject to the CWA,
suggested that work stop absent a permit from the Corps.
Six months later, EPA issued the Sacketts a formal
administrative compliance order. The order stated that the
property contained wetlands subject to the CWA. It went on
to explain that the Sacketts’ placement of fill material onto
half an acre of their property without a discharge permit
constituted a violation of the CWA. The Sacketts were
ordered to “immediately undertake activities to restore the
Site” in keeping with a “Restoration Work Plan” provided
by EPA, and they were given five months to complete the
remediation. The order also informed the Sacketts that
failure to comply could result in civil and administrative
penalties of over $40,000 per day.

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SACKETT V. USEPA 9
C.
On April 28, 2008, shortly before the deadline for
compliance, the Sacketts sued EPA, seeking declaratory and
injunctive relief. The Complaint alleged that the agency’s
issuance of the compliance order was arbitrary and
capricious under the Administrative Procedure Act
(“APA”), 5 U.S.C. § 706(2), because it was premised on an
erroneous assertion of jurisdiction under the CWA.2
On May 15, 2008, EPA and the Corps again inspected
the site. EPA wetlands ecologist John Olson took field notes
on the property and its surroundings, and he completed a
seven-page jurisdictional determination (“JD”), in which he
concluded that the Sacketts’ lot contained wetlands subject
to regulation under the CWA.
That same day, after Olson reported his findings to his
superiors at the agency, EPA issued the Sacketts an amended
compliance order that extended the dates for compliance but
otherwise mirrored the original order. The amended order
reiterated that the property contained wetlands subject to
CWA regulation, that the Sacketts’ discharge of fill material
was pollution in violation of the CWA, and that their
continued noncompliance could result in significant
monetary sanctions. The amended compliance order
“supersede[d] and replace[d]” the original compliance order.
Six weeks later, on July 1, 2008, Olson authored a
memorandum (the “July 2008 Memo”), in which he
memorialized his observations from the May site visit. The
2 The Complaint also alleged violations of the Sacketts’ substantive
and procedural due process rights, but those claims were dropped in the
Amended Complaint and are not at issue in this appeal. See Sackett v.
EPA, 566 U.S. 120, 125 (2012).

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10 SACKETT V. USEPA
memo contains photographs from the visit that depict
flooded soils and wetland vegetation on the Sacketts’ lot in
areas not yet covered with fill. Two such photos are included
in an appendix to this opinion.
EPA moved to dismiss the Sacketts’ lawsuit, contending
that the original compliance order was not “final agency
action . . . subject to judicial review” under the APA.3
5 U.S.C. § 704. The district court granted the motion, and
our court affirmed, concluding that the CWA precludes pre-
enforcement judicial review of compliance orders. See
Sackett v. EPA, 622 F.3d 1139, 1147 (9th Cir. 2010). But
the Supreme Court granted certiorari and reversed, holding
that the original compliance order constituted “final agency
action” subject to judicial review under the APA. Sackett v.
EPA, 566 U.S. 120, 131 (2012).
On remand, the Sacketts amended their Complaint to
challenge the amended compliance order, and district court
proceedings continued for seven more years. In March
2019, the district court entered summary judgment in EPA’s
favor, holding that the agency’s issuance of the amended
compliance order was not arbitrary or capricious. In the
same order, the district court denied a motion by the Sacketts
to strike from the administrative record the July 2008 Memo
and materials referenced therein but also explained that
summary judgment would have been appropriate even if
those materials were not considered.
The Sacketts timely appealed both the grant of summary
judgment and the denial of the motion to strike. Following
3 Because the Sacketts filed their Complaint before the amended
compliance order issued, only the original compliance order was at issue
at this stage in the court proceedings.

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SACKETT V. USEPA 11
an unsuccessful attempt at mediation, the Sacketts filed their
opening brief in December 2019. After we granted EPA two
filing extensions for its opposition brief, the agency sent the
Sacketts a two-paragraph letter in March 2020, withdrawing
the amended compliance order issued twelve years prior. In
the letter, the agency explained that “several years ago EPA
decided to no longer enforce the [order] against you.” The
letter assured the Sacketts that “EPA does not intend to issue
a similar order to you in the future for this Site.”
EPA then moved to dismiss the appeal as moot.
According to the agency, its withdrawal of the amended
compliance order effectively granted the Sacketts complete
relief, which mooted the case. The Sacketts disagreed,
explaining that the status of their property remains unsettled
and that EPA did not withdraw the 2008 JD, in which Olson
concluded that the agency has authority under the CWA to
regulate the Sacketts’ property.4
II.
A.
We review de novo whether a case has become moot.
Biodiversity Legal Found. v. Badgley, 309 F.3d 1166, 1173
(9th Cir. 2002). “A case that becomes moot at any point
during the proceedings is ‘no longer a “Case” or
“Controversy” for purposes of Article III,’ and is outside the
4 In an unpublished order, a motions panel denied the motion to
dismiss without prejudice to EPA’s renewing the argument in
opposition, which EPA did. That prior ruling does not eliminate the need
for us to reassess this jurisdictional question. See Sanchez v. City of
Santa Ana, 936 F.2d 1027, 1032 n.3 (9th Cir. 1990) (explaining that a
merits panel has an independent duty to determine whether it has
jurisdiction, even if a motions panel already ruled on the issue).

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jurisdiction of the federal courts.” United States v. Sanchez-
Gomez, 138 S. Ct. 1532, 1537 (2018) (quoting Already, LLC
v. Nike, Inc., 568 U.S. 85, 91 (2013)). A party asserting
mootness “bears the heavy burden of establishing that there
remains no effective relief a court can provide.” Bayer v.
Neiman Marcus Grp., Inc., 861 F.3d 853, 862 (9th Cir.
2017). “‘The question is not whether the precise relief
sought at the time the case was filed is still available,’ but
‘whether there can be any effective relief.’” Id. (quoting
McCormack v. Herzog, 788 F.3d 1017, 1024 (9th Cir.
2015)).
The already “heavy burden” of establishing mootness is
even heavier for EPA here because its mootness argument
stems from its own voluntary conduct—namely its decision
to withdraw the amended compliance order. When a
defendant voluntarily ceases challenged conduct, mootness
follows only “if subsequent events [make] it absolutely clear
that the allegedly wrongful behavior could not reasonably be
expected to recur.” Friends of the Earth, Inc. v. Laidlaw
Env’t Servs. (TOC), Inc., 528 U.S. 167, 189 (2000)
(emphasis added) (quoting United States v. Concentrated
Phosphate Exp. Ass’n, 393 U.S. 199, 203 (1968)).
In deciding whether EPA has met its burden of
establishing that its letter withdrawing the amended
compliance order mooted this case, our decision in Porter v.
Bowen, 496 F.3d 1009 (9th Cir. 2007), is instructive. In
Porter, the operators of websites that encouraged interstate
“vote swapping” for the 2000 presidential election brought a
§ 1983 action against the California Secretary of State after
the Secretary had threatened one of them with criminal
prosecution. Id. at 1012. While the lawsuit was pending,
doubts apparently arose about whether California law
actually criminalized this activity, and the Secretary sent a

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SACKETT V. USEPA 13
letter to the Speaker of the California State Assembly
explaining that the State would not pursue prosecutions
unless the state legislature clarified the relevant election
laws. Id. at 1016.5 The district court held that this letter
from the Secretary rendered the plaintiffs’ claim for
prospective relief moot. Id.
We reversed, holding that the Secretary “fail[ed] to carry
the ‘heavy burden’ of establishing that it is ‘absolutely clear’
that California will not threaten to prosecute the owners of
[the websites] if they create vote-swapping websites in the
future.” Id. at 1017. We explained that the letter “d[id] not
suggest that it [wa]s binding on the Secretary of State,” and
that a new Secretary of State who had since entered office
“could initiate the prosecution of vote-swapping websites at
her discretion.” Id. Finally, we observed that “the Secretary
has maintained throughout the nearly seven years of
litigation . . . that [the Secretary] had the authority under
state law to threaten [the plaintiffs] with prosecution,” a
position that the plaintiffs believed violated their rights. Id.
The Sacketts’ situation is directly analogous. EPA’s
stated intention not to enforce the amended compliance order
or issue a similar one in the future does not bind the agency,
and EPA could potentially change positions under new
leadership. Further, the letter did nothing to alter EPA’s
position throughout this litigation that it has authority to
regulate the Sacketts’ property. Indeed, during oral
argument, counsel for the agency was unwilling to represent
that the agency lacked authority over the property and, even
after more than a decade of litigation, could not answer
questions about whether the Sacketts could develop their
land. The agency could have disavowed the JD, but it
5 Presumably this would have required a statutory amendment.

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14 SACKETT V. USEPA
declined to do so. Accordingly, because we cannot conclude
that it is “absolutely clear” that EPA will not either reinstate
the amended compliance order (or issue a new one), this case
is not moot.
EPA’s arguments to the contrary are unavailing. First,
EPA contends that the “inscribed-by-hand, unsigned, never-
issued” JD, which it refused to disavow, cannot be
considered “final agency action.” But this is a red herring.
Even if the 2008 JD itself would not constitute “final agency
action” required to bring an APA claim because it lacks the
“hallmarks of APA finality,” see Sackett, 566 U.S. at 126,
that is beside the point. The “final agency action”
requirement was already satisfied by the original compliance
order when the Sacketts filed this lawsuit, as the Supreme
Court specifically held. Id. at 131; see also United Steel,
Paper & Forestry, Rubber, Mfg., Energy, Allied Indus. &
Serv. Workers Int’l Union v. Shell Oil Co., 602 F.3d 1087,
1091–92 (9th Cir. 2010) (explaining that “post-filing
developments” do not defeat statutory requirements for
jurisdiction “if jurisdiction was properly invoked as of the
time of filing”). The question we now face is whether the
agency can end the litigation by voluntarily withdrawing the
challenged order. As the Supreme Court has emphasized,
whether a suit may be initiated and whether it may be
terminated as moot are different inquiries. Cf. Laidlaw,
528 U.S. at 190 (“[T]here are circumstances in which the
prospect that a defendant will engage in (or resume) harmful
conduct may be too speculative to support standing, but not
too speculative to overcome mootness.”).
Accordingly, we conclude that the JD is relevant not
because of its potential to serve as “final agency action,” but
rather because it demonstrates EPA’s refusal to concede that
it lacks the authority to regulate the Sacketts’ land. See Fikre

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SACKETT V. USEPA 15
v. FBI, 904 F.3d 1033, 1037 (9th Cir. 2018) (explaining that,
when asserting mootness due to voluntary cessation, the
government must “demonstrate that the change in its
behavior is ‘entrenched’ or ‘permanent’” (quoting
McCormack, 788 F.3d at 1025)). As long as EPA avoids
disclaiming authority to regulate the Sacketts’ property, the
core of this dispute is alive and well.
Second, EPA argues that the Sacketts already received
“full relief” when the agency withdrew its amended
compliance order. Again, we disagree. EPA’s argument
ignores the practical realities of the Sacketts’ predicament.
If we were to dismiss this case as moot, the Sacketts would
not have prevailed in any meaningful sense; rather, they
would be stuck in the same regulatory quagmire they have
been in for the past thirteen years. As we have explained,
nothing prevents the agency from reinstating the amended
compliance order, issuing a new one, or possibly even
pursuing another avenue of enforcement available to it under
the CWA. Withdrawal of the amended compliance order,
therefore, hardly affords the Sacketts “full relief.” See
United States v. Tanoue, 94 F.3d 1342, 1344 (9th Cir. 1996).
By contrast, if we were to side with the Sacketts on the merits
and grant the requested declaratory relief, they would finally
be on solid ground when resuming construction.
The fact that the Sacketts’ central legal challenge
remains unresolved distinguishes this case from the
authorities relied on by EPA. In Oregon Natural Resources
Council v. Grossarth, 979 F.2d 1377 (9th Cir. 1992), for
example, the plaintiffs challenged a proposed timber sale by
the U.S. Forest Service, alleging in part that the Forest
Service had failed to prepare a required Environmental
Impact Statement (“EIS”). Id. at 1378. While the case was
pending, the plaintiffs simultaneously pursued an

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16 SACKETT V. USEPA
administrative appeal and prevailed, causing the Forest
Service to halt the sale and order that an EIS be prepared. Id.
We held that this intervening administrative order mooted
the appeal. Id. at 1379–80. We reasoned that the Forest
Service’s cancellation of the sale and its decision to prepare
an EIS “was not a voluntary cessation within the meaning of
that doctrine, but was instead the result of [the plaintiffs’]
successful administrative appeal. Accordingly, [the
plaintiffs’] invocation of the voluntary cessation theory
[wa]s misplaced.” Id. at 1379. We further held that, even if
the Forest Service’s conduct could be considered voluntary
cessation, the record contained “no basis on which we could
form a ‘reasonable expectation’ that there [would] be a
recurrence of the same allegedly unlawful conduct by the
Forest Service in the future.” Id.
The situation facing the Sacketts is distinguishable in
both respects. EPA’s decision to withdraw the amended
compliance order was not the result of a judgment from an
intervening administrative proceeding. The agency
provided no explanation for why, “several years ago,” it
resolved not to enforce the amended compliance order
against the Sacketts, but it appears to have been a voluntary
agency decision. Moreover, there is evidence in the record
from which we could form a “reasonable expectation” that
the same allegedly unlawful conduct by EPA could recur,
given that the agency apparently still believes it has authority
under the CWA to regulate the Sacketts’ property.
Third, to bolster its claim that the case is moot, EPA
invokes the general presumption of good faith that the
government traditionally enjoys in the context of mootness
by voluntary cessation. See Am. Cargo Transp., Inc. v.
United States, 625 F.3d 1176, 1180 (9th Cir. 2010) (“The
government’s change of policy presents a special

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SACKETT V. USEPA 17
circumstance in the world of mootness. . . . [U]nlike in the
case of a private party, we presume the government is acting
in good faith.”). But this presumption is by no means
dispositive. In Fikre, for example, a district court had
dismissed as moot a plaintiff’s lawsuit challenging his
placement on the No Fly List after the FBI restored the
plaintiff’s flying privileges during the litigation. See
904 F.3d at 1036–37. We reversed, and although we
acknowledged that the FBI benefitted from a presumption of
good faith, we explained that the “government must still
demonstrate that the change in its behavior is ‘entrenched’
or ‘permanent’” to moot a case. Id. at 1037–38 (quoting
McCormack, 788 F.3d at 1025). We observed that the FBI’s
decision to remove the plaintiff from the list during the
litigation was “an individualized determination untethered to
any explanation or change in policy.” Id. at 1039–40. We
held that, absent an “explanation of [its] reasons . . . the
government has not repudiated the decision to add [him] to
the No Fly List and maintain him there for approximately
five years.” Id. at 1040. We further reasoned that “[b]ecause
there are neither procedural hurdles to reinstating [the
plaintiff] on the No Fly List . . . nor any renouncement by
the government of its . . . authority to do so, the voluntary
cessation doctrine applies . . . [and the plaintiff’s] due
process claims are not moot.” Id. at 1041.
Here, although we similarly presume EPA withdrew its
amended compliance order in good faith, the agency’s
conduct prevents that presumption from carrying the day.
As explained, we are not confident that the agency has
permanently ceased attempting to regulate the Sacketts’
land. In addition, we note that, although EPA represents that
it resolved “several years ago” not to enforce the amended
compliance order, it informed the Sacketts of this
development only on the eve of EPA’s filing deadline for its

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18 SACKETT V. USEPA
opposition brief—a deadline we had already extended twice,
in response to requests from the agency that had not
mentioned any change in the agency’s enforcement
intentions. Cf. id. at 1040. If we are to take EPA’s letter at
face value, the agency caused the Sacketts to litigate cross-
motions for summary judgment in the district court,
participate in mediation, and then pursue this appeal after the
agency had already concluded it would never enforce the
challenged compliance order. Forcing the Sacketts to
engage in years of litigation, under threat of tens of
thousands of dollars in daily fines, only to assert at the
eleventh hour that the dispute has actually been moot for a
long time, is not a litigation strategy we wish to encourage.
Lastly, EPA argues that the new definition of “waters of
the United States” it adopted in 2020, see 85 Fed. Reg.
22,250, 22,273 (Apr. 21, 2020), governs its authority over
wetlands such that any judicial decision regarding the prior
regulation “would be purely advisory.” But the Sacketts’
primary legal argument is that they “are entitled to prevail as
a matter of law based on the unambiguous text of the [CWA]
as interpreted by the Rapanos plurality, no matter what
regulatory interpretation EPA adopts.” Therefore, a decision
resolving whether the Sacketts’ interpretation of the CWA is
correct will not be purely advisory.
At bottom, the central dispute in this case remains
unresolved. The Sacketts are still, thirteen years later,
seeking an answer to whether EPA can prevent them from
developing their property. Accordingly, we hold that this
case is not moot.
B.
Before turning to the merits, we address the district
court’s refusal to strike Olson’s July 2008 Memo from the

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SACKETT V. USEPA 19
administrative record.6 We review that ruling for abuse of
discretion. Sw. Ctr. for Biological Diversity v. U.S. Forest
Serv., 100 F.3d 1443, 1447 (9th Cir. 1996).
A court reviews agency action under the APA by
considering the “whole record” that was before the agency
when it undertook the challenged action. 5 U.S.C. § 706; see
also Camp v. Pitts, 411 U.S. 138, 142 (1973) (per curiam)
(holding that “the focal point for judicial review” of whether
agency action is arbitrary and capricious “should be the
administrative record already in existence, not some new
record made initially in the reviewing court”). The Sacketts
contend that, because the July 2008 Memo postdated the
amended compliance order, it was wrongly included in the
administrative record.
We hold that the district court did not abuse its discretion
in permitting EPA to include the July 2008 Memo in the
administrative record. Although the memo postdates the
issuance of the amended compliance order by six weeks, it
simply memorializes the observations and conclusions that
Olson and a Corps official made during their May site visit
and attaches other information available to EPA before the
order issued. Specifically, the memo consists of photos
Olson took during the May site visit, historical aerial photos
that Olson had examined “[p]rior to visiting the site,” general
maps of the area, Olson’s observations from the May site
6 In the district court, the Sacketts moved to strike additional
documents that were cited in the July 2008 Memo. On appeal, however,
the Sacketts only provide argument on why the July 2008 Memo itself
should be stricken. We therefore consider only whether that memo was
appropriately included in the administrative record. See Miller v.
Fairchild Indus., Inc., 797 F.2d 727, 738 (9th Cir. 1986) (“The Court of
Appeals will not ordinarily consider matters on appeal that are not
specifically and distinctly argued in appellant’s opening brief.”).

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20 SACKETT V. USEPA
visit, and descriptions of the “[e]cology and hydrology of the
Sackett wetland” based on observations made during that
site visit. Thus, the memo does not contain the sort of “‘post
hoc’ rationalizations” that do not belong in an administrative
record. Citizens to Preserve Overton Park, Inc. v. Volpe,
401 U.S. 402, 419 (1971) (quoting Burlington Truck Lines
v. United States, 371 U.S. 156, 168 (1962)), abrogated on
other grounds by Califano v. Sanders, 430 U.S. 99 (1977).
Indeed, the record shows that the July 2008 Memo
repeats the observations that informed the challenged agency
action. Declarations from EPA officials establish that,
shortly after his site visit, Olson called EPA’s Regional
Counsel to relay his findings and his conclusion that the
Sackett property contained wetlands subject to the CWA.
The Regional Counsel then relayed Olson’s findings to
EPA’s Office of Ecosystems, Tribal, and Public Affairs, and
recommended based on those findings that the Office issue
the amended compliance order. Because the July 2008
Memo thus conveys the same information that the agency
considered and relied on in issuing the amended compliance
order, we cannot say the district court abused its discretion
in declining to strike it from the record. Cf. Thompson v.
United States Dep’t of Lab., 885 F.2d 551, 555 (9th Cir.
1989) (explaining that the “whole administrative record” for
purposes of judicial review of agency action includes
materials “directly or indirectly considered by agency
decision-makers” (emphasis omitted) (quoting Exxon Corp.
v. Dep’t of Energy, 91 F.R.D. 26, 33 (N.D. Tex. 1981))).
C.
We now turn to whether EPA was entitled to summary
judgment on the merits. We review the district court’s grant
of summary judgment de novo. Nw. Env’t Advocs. v. EPA,
537 F.3d 1006, 1014 (9th Cir. 2008). The Sacketts’ core

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SACKETT V. USEPA 21
argument is premised on interpreting Justice Scalia’s
plurality opinion in Rapanos v. United States, 547 U.S. 715
(2006), as providing the governing standard for determining
CWA jurisdiction over wetlands.7 In Rapanos, the Court
considered “whether four Michigan wetlands, which lie near
ditches or man-made drains that eventually empty into
7 The Sacketts also argue that EPA failed to comply with the Corps’
1987 Wetlands Delineation Manual when evaluating their property, and
that their property does not contain wetlands at all. We reject both
arguments. Even assuming the 1987 Manual was still operative, but see
Tin Cup, LLC v. U.S. Army Corp of Eng’rs, 904 F.3d 1068, 1072 (9th
Cir. 2018), EPA complied with the manual here. The manual identifies
a procedure for identifying wetlands in “atypical situations,” such as
when “recent human activities” have resulted in “removal of vegetation”
and “placement of dredged or fill material over hydric soils.” In this
circumstance, the agency is instructed to try and “determine the type of
vegetation that previously occurred,” including by consulting recent
aerial photography, conducting onsite inspections, and observing
adjacent vegetation. EPA did all of those things here.
As for EPA’s conclusion that there were in fact wetlands on the
property, we review the agency’s conclusion for substantial evidence.
Ctr. for Biological Diversity v. Esper, 958 F.3d 895, 910 (9th Cir. 2020).
That standard is easily satisfied. The applicable regulations define
wetlands as “those areas that are inundated or saturated by surface or
ground water at a frequency and duration sufficient to support, and that
under normal circumstances do support, a prevalence of vegetation
typically adapted for life in saturated soil conditions.” 33 C.F.R.
§ 328.3(b) (2008). During his May 2008 site visit, Olson “observed that
all portions of the Sackett property where native soil was removed but
fill material had not been placed . . . were inundated or ponded/saturated
to the surface.” Olson’s photos from the site visit corroborate these
observations. EPA’s inspection report from the prior year further
explained that “strips of excavated ground revealed wetland soils” on the
Sacketts’ lot and that the vegetation on the south end of the lot “consisted
of the wetland species.” Photos from the 2007 site visit reflect such
conditions. Representative photos from both the 2007 and 2008 site
visits are included in an appendix to this opinion. We therefore proceed
on the understanding that the Sacketts’ property contains wetlands.

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22 SACKETT V. USEPA
traditional navigable waters, constitute[d] ‘waters of the
United States’ within the meaning of the [CWA].” Id. at 729
(plurality opinion). The Sixth Circuit approved of the Corps’
assertion of jurisdiction under the applicable regulations,
which included as “waters of the United States” wetlands
that were “adjacent” to any tributary that fed a navigable
water. Id. at 729–30. The Court held that the Sixth Circuit
had applied the wrong legal standard to evaluate whether the
wetlands fell within the scope of the CWA, and that a
remand was necessary. Id. at 757.
No opinion garnered a majority. Justice Scalia, writing
for four Justices, rejected the regulatory definition of
“adjacency” and instead concluded that, under the statute,
“waters of the United States” extend only to “relatively
permanent, standing or flowing bodies of water” and to
wetlands with a “continuous surface connection” to such
permanent waters. Id. at 739, 742.
Justice Kennedy concurred in the judgment. He
accepted the regulatory definition of adjacency, id. at 775
(Kennedy, J., concurring in the judgment), but he rejected
the Corps’ position that wetlands are necessarily “waters of
the United States” any time they are “bordering, contiguous
[with], or neighboring” a tributary, 33 C.F.R. § 328.3(c)
(2008), “however remote and insubstantial, that eventually
may flow into traditional navigable waters.” Id. at 778.
Justice Kennedy interpreted the CWA as imposing an
additional requirement for regulatory jurisdiction over
wetlands: “jurisdiction over wetlands depends upon the
existence of a significant nexus between the wetlands in
question and navigable waters in the traditional sense.” Id.
at 779. This “significant nexus” inquiry would turn on
whether the wetlands, “either alone or in combination with
similarly situated lands in the region, significantly affect the

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SACKETT V. USEPA 23
chemical, physical, and biological integrity of other covered
waters more readily understood as ‘navigable.’”8 Id. at 780.
Although the Scalia plurality did not entirely reject the
concept of a “significant nexus,” which derived from earlier
Supreme Court caselaw, it opined that only wetlands with a
“physical connection” to traditional navigable waters had the
requisite nexus to qualify as “waters of the United States.”
Id. at 755 (plurality opinion).
The Sacketts argue that the Scalia plurality provides the
governing legal standard. They further argue that, because
their property does not contain wetlands with a continuous
surface connection to any “waters of United States,” the
agency’s assertion of jurisdiction over their property ran
afoul of the CWA and the APA.
In interpreting Rapanos to evaluate this argument, we are
not writing on a blank slate. In Northern California River
Watch v. City of Healdsburg, 496 F.3d 993 (9th Cir. 2007),
we concluded that “Justice Kennedy’s concurrence provides
the controlling rule of law” from Rapanos. Id. at 999–1000.
To reach this determination, we engaged in the inquiry the
Supreme Court established in Marks v. United States,
430 U.S. 188 (1977), under which the controlling holding of
a fractured decision is “the narrowest ground to which a
majority of the Justices would assent if forced to choose in
almost all cases.” Healdsburg, 496 F.3d at 999. In
determining that narrowest ground, we relied heavily on the
Seventh Circuit’s decision in United States v. Gerke
8 Consistent with Riverside Bayview Homes, Justice Kennedy infers
that this significant nexus requirement is satisfied when a wetland
directly abuts on a traditional navigable water. Rapanos, 547 U.S.
at 780.

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24 SACKETT V. USEPA
Excavating, Inc., 464 F.3d 723 (7th Cir. 2006) (per curiam),
which likewise applied Marks to conclude that the Kennedy
concurrence supplied the controlling rule in Rapanos.
Healdsburg, 496 F.3d at 999–1000. Under Healdsburg,
therefore, our circuit’s law is that Justice Kennedy’s
understanding of “significant nexus” provides the governing
standard for determining when wetlands are regulable under
the CWA.
The Sacketts contend that a later en banc decision of our
court fatally undermines Healdsburg such that it is no longer
law of the circuit. In United States v. Davis, 825 F.3d 1014
(9th Cir. 2016) (en banc), we clarified how we perform a
Marks analysis to interpret a fractured decision. We
reflected “that the Marks inquiry at times has ‘baffled and
divided the lower courts that have considered it,’” and we
observed that two approaches to applying Marks had come
to predominate: a reasoning-based approach and a results-
based approach. Id. at 1020–21 (quoting Nichols v. United
States, 511 U.S. 738, 746 (1994)). Under the reasoning-
based approach, courts “look to those opinions that
concurred in the judgment and determine whether one of
those opinions sets forth a rationale that is the logical subset
of other, broader opinions. When, however, no common
denominator of the Court’s reasoning exists, we are bound
only by the specific result.” Id. at 1028 (quotation marks
omitted). Under the results-based approach, the controlling
holding from the fractured case in question is the rule that
“would necessarily produce results with which a majority of
the Justices . . . would [have] agree[d].” Id. at 1021 (quoting
Planned Parenthood of Se. Pa. v. Casey, 947 F.2d 682, 694
(3d Cir. 1991), aff’d in part, rev’d in part, 505 U.S. 833
(1992)). Our court in Davis embraced the reasoning-based
approach, see id. at 1028, and we remain bound by that
holding.

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SACKETT V. USEPA 25
The Sacketts argue that the court in Healdsburg did not
employ a reasoning-based framework when performing its
Marks analysis of Rapanos, and they contend that
Healdsburg is therefore no longer good law after Davis. We
disagree.9 In our circuit, a three-judge panel may abandon
the holding of a prior panel only when intervening higher
authority is “clearly irreconcilable” with that earlier panel
opinion. Miller v. Gammie, 335 F.3d 889, 900 (9th Cir.
2003) (en banc). Therefore, we will disregard Healdsburg
only if it is clearly irreconcilable with our en banc decision
in Davis.
It is not. We explained in Davis that the narrowest
opinion for purposes of a Marks analysis is the opinion that
concurs in the judgment that is “the logical subset of other,
broader opinions,” and which therefore represents “a
common denominator of the Court’s reasoning.” Davis,
825 F.3d at 1028. In Healdsburg, our Marks analysis
consisted of a single paragraph that endorsed the Seventh
Circuit’s Marks analysis in Gerke. See Healdsburg,
496 F.3d at 999–1000.
Gerke, in turn, elaborated on why the Kennedy
concurrence articulated a narrower ground for reversing than
did the Scalia plurality such that “the Kennedy concurrence
is the least common denominator.” Gerke, 464 F.3d at 725.
9 A prior decision of our court considered this precise question. In
United States v. Robertson, 875 F.3d 1281 (9th Cir. 2017), we held that
Healdsburg was not clearly irreconcilable with Davis and therefore
remained law of the circuit. Id. at 1291–92. But the Supreme Court
summarily vacated the judgment in that case because the defendant died
while his petition for certiorari was pending. See Robertson v. United
States, 139 S. Ct. 1543 (2019) (Mem.) (granting writ of certiorari,
vacating the judgment, and remanding “for consideration of the question
whether the case is moot”).

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26 SACKETT V. USEPA
The two opinions begin on common ground, as Justice
Kennedy had himself expressed. Rapanos, 547 U.S. at 767
(Kennedy, J., concurring in the judgment) (“The plurality’s
opinion begins from a correct premise. As the plurality
points out . . . in enacting the [CWA] Congress intended to
regulate at least some waters that are not navigable in the
traditional sense.”). Gerke recognized that the plurality and
the concurrence also agreed that for wetlands to fall within
CWA jurisdiction, they had to share some connection with
traditional navigable waters. See 464 F.3d at 724–25. As
the Seventh Circuit further explained, “[t]he plurality
Justices thought that Justice Kennedy’s ground for reversing
was narrower than their own. . . . Justice Kennedy expressly
rejected two ‘limitations’ imposed by the plurality on federal
authority over wetlands under the Clean Water Act.” Id.
at 724 (quoting Rapanos, 547 U.S. at 768).
Admittedly, Gerke’s analysis does not fit neatly into
either a reasoning-based or a results-based Marks
framework, and portions of the opinion are consistent with
the results-based Marks analysis that we rejected in Davis.
See, e.g., id. (explaining that Justice Kennedy’s approach
will yield a result that will command five votes “in most
cases”) (emphasis omitted). The results-based aspects of
Gerke present some tension with Davis, but to be superseded
under Miller v. Gammie, “[i]t is not enough for there to be
some tension between the intervening higher authority and
prior circuit precedent, or for the intervening higher
authority to cast doubt on the prior circuit precedent.” Lair
v. Bullock, 697 F.3d 1200, 1207 (9th Cir. 2012) (citation and
quotation marks omitted). Thus, although Gerke is not a
paradigmatic example of a reasoning-based Marks analysis,
it is not “clearly irreconcilable” with such an approach. And
because Healdsburg adopted Gerke’s application of Marks,
we conclude that Healdsburg’s “theory or reasoning” was

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SACKETT V. USEPA 27
likewise not clearly undercut by Davis. Miller, 335 F.3d
at 900.
The Sacketts also contend that Healdsburg is clearly
irreconcilable with intervening authority in another way.
They argue that Healdsburg relied on the Rapanos dissent in
its Marks analysis, and that shortly after Davis, we held that
dissents could not be considered for purposes of a Marks
analysis. The Sacketts cite to our decision in Cardenas v.
United States, 826 F.3d 1164 (9th Cir. 2016), in which we
wrote that the “narrowest opinion must represent a common
denominator of the Court’s reasoning; it must embody a
position implicitly approved by at least five Justices who
support the judgment.” Id. at 1171 (emphasis added)
(quoting Davis, 825 F.3d at 1020). But this language in
Cardenas is no more than a direct quotation from Davis, a
decision in which we explicitly reserved judgment on the
very question that the Sacketts assert Cardenas decided.
Davis, 825 F.3d at 1025 (“Here, we assume but do not decide
that dissenting opinions may be considered in a Marks
analysis.”); id. at 1025 n.12 (“We note that . . . the D.C.
Circuit explicitly stated that it was not free to combine a
dissent with a concurrence to form a Marks majority. We
emphasize here, however, that we do not decide that issue.”
(quotation marks and citation omitted)). Thus, Davis cannot
stand for the proposition that dissents are off-limits in a
Marks inquiry, and neither can Cardenas, which cited Davis
only in passing and did not consider that question.10
10 We also note that a three-judge panel decision such as Cardenas
could not have superseded Healdsburg, an earlier decision of our court,
because it is not an intervening higher authority. See Miller, 335 F.3d
at 899.

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28 SACKETT V. USEPA
Moreover, the Sacketts’ argument mischaracterizes
Healdsburg because Healdsburg does not directly or
indirectly depend on the Rapanos dissent, even though
Healdsburg does cite to the dissent in its Marks analysis. As
explained above, Healdsburg relied heavily on Gerke.
Later, when rejecting an argument that Gerke improperly
used the Rapanos dissent in its Marks analysis, the Seventh
Circuit clarified that Gerke had not relied on the dissent. The
Seventh Circuit explained that, in Gerke, the operative
narrower-grounds inquiry compared the concurrence and the
plurality, and that, although Gerke did make “the same
narrower-grounds point in comparing the concurrence with
the dissenting opinion . . . that comparison was not necessary
to resolving the appeal, so it was dicta.” Gibson v. Am.
Cyanamid Co., 760 F.3d 600, 621 (7th Cir. 2014). Because
Healdsburg primarily relied on Gerke, we similarly
conclude that the mention of the Rapanos dissent in
Healdsburg does not indicate that Healdsburg relied on that
dissent.
For all these reasons, the Sacketts’ arguments fail, and
Healdsburg remains law of the circuit—meaning the
Kennedy concurrence is still the controlling opinion from
Rapanos.11
11 The Sacketts further contend that County of Maui v. Hawaii
Wildlife Fund, 140 S. Ct. 1462 (2020), makes clear that the Scalia
plurality provides the Court’s authoritative opinion on the meaning of
the CWA. It is true that in County of Maui, all four opinions refer only
to the Rapanos plurality when interpreting the CWA. See, e.g., id.
at 1478 (Kavanaugh, J., concurring) (noting that the majority’s reading
of “discharge” “adheres to the interpretation set forth in Justice Scalia’s
plurality opinion in Rapanos”). But County of Maui did not concern the
scope of “waters of the United States.” The question presented in County
of Maui was an entirely different one—the meaning of pollution from a

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SACKETT V. USEPA 29
D.
We therefore apply Justice Kennedy’s “significant
nexus” inquiry to evaluate whether EPA has jurisdiction to
regulate the Sacketts’ property. In answering this question,
we also use the regulations that were in effect when EPA
issued the amended compliance order.12 See United States
v. Lucero, 989 F.3d 1088, 1104–05 (9th Cir. 2021) (holding
that the definition of “waters of the United States” from the
regulation that was in place at the time of the defendant’s
conduct applied, despite the promulgation of a new
regulation that narrowed that definition while the case was
pending on appeal). The Sacketts’ only challenge to those
regulations is premised on the Scalia plurality being the
controlling opinion.
Under the APA, a court may set aside agency action if it
is “arbitrary, capricious . . . or otherwise not in accordance
with law.” 5 U.S.C. § 706(2)(A). “The scope of review
under the ‘arbitrary and capricious’ standard is narrow and a
point source under the CWA, id. at 1468 (majority opinion)—so there
was no reason to rely on the distinctions between the Scalia plurality and
the Kennedy concurrence in Rapanos. See Hawai‘i Wildlife Fund v.
County of Maui, 886 F.3d 737, 748 (9th Cir. 2018) (“In past cases, we
have recognized Justice Kennedy’s concurrence in Rapanos . . . as
controlling. But we have only done so in the context of ‘determin[ing]
whether a wetland that is not adjacent to and does not contain a
navigable-in-fact water is subject to the CWA.’” (quoting Robertson,
875 F.3d at 1288–89)), vacated and remanded, 140 S. Ct. 1462. County
of Maui is thus inapposite here and does not disturb our interpretation of
Rapanos.
12 The Sacketts object to the district court’s citation to agency
guidance issued after the amended compliance order. We need not
address this argument because we do not rely for any part of our analysis
on that agency guidance.

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30 SACKETT V. USEPA
court is not to substitute its judgment for that of the agency.”
Motor Vehicle Mfrs. Ass’n v. State Farm Mut. Auto. Ins. Co.,
463 U.S. 29, 43 (1983). “As a reviewing court, we must
consider whether the decision was based on a consideration
of the relevant factors and whether there has been a clear
error of judgment.” San Luis & Delta-Mendota Water Auth.
v. Jewell, 747 F.3d 581, 601 (9th Cir. 2014) (quotation marks
omitted). “Where the agency has relied on relevant evidence
. . . that a reasonable mind might accept as adequate to
support a conclusion, its decision is supported by substantial
evidence, and this court must affirm the agency’s finding.”
Ctr. for Biological Diversity v. Esper, 958 F.3d 895, 910
(9th Cir. 2020) (quotation marks and brackets omitted).
It is clear that the requirements of the Kennedy
concurrence and the applicable regulations are satisfied here.
The record plainly supports EPA’s conclusion that the
wetlands on the Sacketts’ property are adjacent to a
jurisdictional tributary and that, together with the similarly
situated Kalispell Bay Fen, they have a significant nexus to
Priest Lake, a traditional navigable water.
First, there was nothing arbitrary about EPA’s
determination that the Sacketts’ wetlands were adjacent to a
jurisdictional tributary, and thus fell into the relevant
regulatory definition of “waters of the United States.”
33 C.F.R. § 328.3(a)(1), (5), (7) (2008) (defining a wetland
that is adjacent to a tributary of a traditional navigable water
as a water of the United States). At the time of the
challenged compliance order, artificial barriers did not
defeat adjacency. See id. § 328.3(c) (“Wetlands separated
from other waters of the United States by man-made dikes
or barriers . . . and the like are ‘adjacent wetlands.’”); see
also Rapanos, 547 U.S. at 780. EPA therefore properly
concluded that the wetlands on the Sacketts’ lot were

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SACKETT V. USEPA 31
adjacent to the unnamed tributary to Kalispell Creek thirty
feet away, notwithstanding that Kalispell Bay Road lies in
between the property and the tributary.13 Officials from the
site visit also observed that the tributary is “relatively
permanent” based on U.S. Geological Survey mapping as
well as its flow, channel size, and form. Moreover, because
this unnamed tributary eventually flows into Priest Lake, a
traditional navigable water, via Kalispell Creek, the tributary
is jurisdictional—that is, it is itself a water of the United
States. See 33 C.F.R. § 328.3(a)(5) (explaining that
tributaries to jurisdictional waters are themselves
jurisdictional). Accordingly, EPA’s conclusion that the
Sacketts’ lot was adjacent to a jurisdictional tributary was
neither arbitrary nor capricious.
We turn next to Justice Kennedy’s “significant nexus”
inquiry: whether “the wetlands, either alone or in
combination with similarly situated lands in the region,
significantly affect the chemical, physical, and biological
integrity of other covered waters more readily understood as
‘navigable.’” Rapanos, 547 U.S. at 780 (Kennedy, J.,
concurring in the judgment).
At the time of the amended compliance order, EPA had
explained that “‘[s]imilarly situated’ wetlands include all
wetlands adjacent to the same tributary.” U.S. EPA & Army
Corps of Engineers, Clean Water Act Jurisdiction Following
the U.S. Supreme Court’s Decision in Rapanos v. United
States & Carabell v. United States (June 5, 2007),
13 EPA and Corps scientists who inspected the site concluded that a
“shallow subsurface flow is occurring” beneath the road, connecting the
Sacketts’ lot to the tributary and the Kalispell Bay Fen wetland system
to the north. This bolsters the agency’s conclusion that the road should
not defeat adjacency.

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32 SACKETT V. USEPA
https://www.epa.gov/sites/production/files/2016-04/docum
ents/rapanosguidance6507.pdf. Here, EPA appropriately
concluded based on the observations from the site visit and
maps of the area that, like the Sacketts’ wetlands, the
Kalispell Bay Fen is adjacent to the unnamed tributary to
Kalispell Creek.14 Therefore, the Sacketts’ wetlands and the
Fen are similarly situated for purposes of evaluating whether
they have a significant nexus to Priest Lake.
The record further supports EPA’s conclusion that these
wetlands, in combination, significantly affect the integrity of
Priest Lake. Water from these wetlands makes its way into
Priest Lake via the unnamed tributary and Kalispell Creek.
According to the July 2008 memo, these wetlands provide
important ecological and water quality benefits; indeed, the
memo identified this wetlands complex, which is one of the
five largest along the 62-mile Priest Lake shoreline, as
“especially important in maintaining the high quality of
Priest Lake’s water, fish, and wildlife.” The agency’s
conclusion that the Sacketts’ wetlands, combined with the
similarly situated Fen, “significantly affect the chemical,
physical, and biological integrity of” Priest Lake was a
reasonable one which we will not second-guess. Rapanos,
547 U.S. at 780 (Kennedy, J., concurring in the judgment);
see also San Luis & Delta-Mendota Water Auth., 747 F.3d
at 621 (emphasizing that “we do not sit as a panel of referees
on a professional scientific journal, but as a panel of
generalist judges obliged to defer to a reasonable judgment
by an agency” (brackets omitted) (quoting City of Los
14 The July 2008 Memo further explained that the Sacketts’ wetlands
and the Fen remain interconnected via a subsurface flow, and historical
aerial photographs establish that they used to be a single wetland
complex, both of which reinforce the agency’s conclusion that the two
are similarly situated.

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SACKETT V. USEPA 33
Angeles v. Dep’t of Transp., 165 F.3d 972, 977 (D.C. Cir.
1999))).
In sum, EPA reasonably determined that the Sacketts’
property contains wetlands that share a significant nexus
with Priest Lake, such that the lot was regulable under the
CWA and the relevant regulations.
III.
For the foregoing reasons, we affirm the district court’s
grant of summary judgment in EPA’s favor.
AFFIRMED.

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34 SACKETT V. USEPA
APPENDIX
View south from Kalispell Bay Road along east edge of
Sackett property, taken during 2008 site visit.

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SACKETT V. USEPA 35
View north from Old Schneiders Road of south and west
edges of property, taken during 2008 site visit.

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36 SACKETT V. USEPA
East side of the lot showing strip of excavated ground that
was being filled when EPA officials arrived, taken during
2007 site visit.

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