United States v. Nicholson ( 2009 )


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  •                    FOR PUBLICATION
    UNITED STATES COURT OF APPEALS
    FOR THE NINTH CIRCUIT
    UNITED STATES OF AMERICA, on its          
    own behalf and as trustee on
    behalf of the Lummi Nation,
    Plaintiff-Appellee,
    v.
    KEITH E. MILNER,
    Defendant,          No. 05-35802
    and                            D.C. No.
    CV-01-00809-RBL
    BRENT C. NICHOLSON; MARY K.
    NICHOLSON,
    Defendants-Appellants,
    v.
    LUMMI NATION,
    Plaintiff-intervener-Appellee.
    
    14457
    14458             UNITED STATES v. NICHOLSON
    UNITED STATES OF AMERICA, on its        
    own behalf and as trustee on
    behalf of the Lummi Nation,
    Plaintiff-Appellee,
    v.
    KEITH E. MILNER,
    Defendant-Appellant,
    SHIRLEY A. MILNER; MARY D.                    No. 05-36126
    
    SHARP; IAN C. BENNETT; MARCIA                   D.C. No.
    A. BOYD,                                    CV-01-00809-RBL
    Defendants-Appellants,
    OPINION
    and
    BRENT C. NICHOLSON; MARY K.
    NICHOLSON,
    Defendants,
    v.
    LUMMI NATION,
    Plaintiff-intervener.
    
    Appeal from the United States District Court
    for the Western District of Washington
    Ronald B. Leighton, District Judge, Presiding
    Argued March 13, 2008
    Submitted October 9, 2009
    Seattle, Washington
    Filed October 9, 2009
    UNITED STATES v. NICHOLSON                      14459
    Before: Betty B. Fletcher, Richard A. Paez and
    Richard C. Tallman,* Circuit Judges.
    Opinion by Judge B. Fletcher
    *Judge Tallman was drawn to replace Judge William W. Schwarzer,
    Senior United States District Judge for the Northern District of California,
    and has read the briefs, reviewed the record, and listened to a recording
    of oral arguments.
    UNITED STATES v. NICHOLSON           14463
    COUNSEL
    Richard M. Stephens, Groen Stephens & Klinge LLP, Belle-
    vue, Washington, for the defendants-appellants.
    Brian Kipnis, Office of the United States Attorney, Seattle,
    Washington, for the plaintiff-appellee.
    Harry L. Johnsen, Raas, Johnsen & Stuen, P.S., Bellingham,
    Washington, for the plaintiff-intervenor-appellee.
    Edgar B. Washburn, Morrison & Foerster LLP, San Fran-
    cisco, California, for Amicus Building Industry Legal
    Defense Foundation.
    John Briscoe, Briscoe Ivester & Bazel LLP, San Francisco,
    California, for Amicus Bay Planning Coalition.
    OPINION
    B. FLETCHER, Circuit Judge:
    In this appeal we decide whether a group of waterfront
    homeowners are liable for common law trespass and viola-
    tions of the Rivers and Harbors Appropriation Act of 1899
    14464                UNITED STATES v. NICHOLSON
    (RHA), 33 U.S.C. § 403, and the Clean Water Act (CWA), 33
    U.S.C. § 1311, because the ambulatory tideland property
    boundary has come to intersect shore defense structures the
    homeowners have erected. In a series of summary judgment
    rulings and after a bench trial, the district court found against
    the homeowners and ordered them to remove violating struc-
    tures and to pay a $1500 civil penalty. We affirm in part and
    reverse in part.
    I.
    In 1855, the United States executed the Treaty of Point
    Elliott with several Indian tribes, thereby acquiring a vast
    swath of what is now western Washington.1 Treaty Between
    the United States and the Dwámish, Suquámish, and Other
    Allied and Subordinate Tribes of Indians in Washington Ter-
    ritory, Jan. 22, 1855, 12 Stat. 927 (1859) (the “Treaty of Point
    Elliott” or the “Treaty”). Under the terms of the Treaty, the
    tribes were relegated to certain reserved areas, including “the
    island called Chah-choo-sen,” on which the Lummi Indian
    Reservation was created for the plaintiff-intervenor, the
    Lummi Nation. 
    Id. at 928.
    Although the Lummi initially occu-
    pied only the island, by an executive order, President Grant in
    1873 expanded the reservation to encompass portions of the
    mainland, including Sandy Point, a sandy spit, all in what is
    now Whatcom County, Washington. Exec. Order (Nov. 22,
    1873), reprinted in 1 Charles J. Kappler, Indian Affairs: Laws
    and Treaties 917 (1904), available at http://digital.library.
    okstate.edu/kappler/Vol1/ Images/v1p0917.jpg. Importantly,
    the order extended the reservation boundaries to “the low-
    water mark on the shore of the Gulf of Georgia.”2 
    Id. In other
      1
    The Treaty of Point Elliott is one of a series of treaties negotiated by
    Territorial Governor Isaac Stevens with various Pacific Northwest Indian
    tribes in the mid-1800s. See generally Washington v. Wash. State Com-
    mercial Passenger Fishing Vessel Ass’n, 
    443 U.S. 658
    , 661-62 (1979);
    Nez Perce Tribe v. Idaho Power Co., 
    847 F. Supp. 791
    , 805-06 (D. Idaho
    1994).
    2
    The “Gulf of Georgia” is now known as the Strait of Georgia.
    UNITED STATES v. NICHOLSON              14465
    words, President Grant explicitly expanded the reservation to
    include the tidelands of the relevant area. United States v.
    Stotts, 
    49 F.2d 619
    , 619, 621 (W.D. Wash. 1930).
    As allowed under President Grant’s executive order, the
    uplands were divided into lots and patented by members of
    the tribe. Defendants-appellants Keith and Shirley Milner (the
    “Milners”), Mary Sharp, Brent and Mary Nicholson (the
    “Nicholsons”), and Ian Bennett and Marcia Boyd
    (“Bennett/Boyd”) (collectively, the “Homeowners”) are the
    successors in interest to some of the parcels derived from
    these original patents. The Homeowners’ parcels all adjoin
    tidelands on the Strait of Georgia.
    Unlike the Homeowners’ properties, the tidelands within
    the Lummi Reservation have otherwise never been alienated.
    Plaintiff-appellee the United States claims that it continuously
    has held the tidelands in trust for the Lummi Nation, pursuant
    to President Grant’s executive order. Not surprisingly, then, it
    is at the boundary between the tidelands and the uplands that
    the present dispute finds its locus.
    Although each property is slightly different, the Homeown-
    ers or their predecessors erected various “shore defense struc-
    tures” to limit erosion and storm damage to their properties.
    The structures generally include “rip rap,” large boulders used
    to dissipate the force of incoming waves, and bulkheads
    placed landward of the rip rap. Between 1963 and 1988, a
    homeowners’ organization (the “Organization”) had leased
    the tidelands from the Lummi Nation, giving waterfront prop-
    erty owners the right to erect shore defense structures on the
    tidelands; however, once the lease expired, both the Organiza-
    tion and the individual Homeowners declined to renew the
    lease.
    Under federal law, the upper boundary of any tidelands is
    the mean high water (MHW) line, which is determined by
    projecting onto the shore the average of all high tides over a
    14466                UNITED STATES v. NICHOLSON
    period of 18.6 years. Borax Consol. Ltd. v. City of Los Ange-
    les, 
    296 U.S. 10
    , 26-27 (1935). Over time, the Sandy Point
    shoreline has eroded significantly, so that as of January 2002,
    the date of the most recent survey in the record, some of the
    Homeowners’ shore defense structures sat seaward of the
    MHW line and within the Lummi tidelands.3 Given the expi-
    ration of the lease, the Homeowners do not have permission
    from the United States or the Lummi Nation to maintain
    structures on the tidelands, and they also lack permits to
    maintain structures in navigable waters of the United States or
    to discharge fill material into the waters of the United States.
    The United States Army Corps of Engineers, and later the
    United States Attorney for the Western District of Washing-
    ton, sent letters to the Homeowners demanding removal of the
    structures or alternatively that the Homeowners enter into
    agreements to lease the tidelands. When the Homeowners did
    not remove the structures, the United States filed virtually
    identical complaints against the separate Homeowners, alleg-
    ing three causes of action: (1) trespass; (2) violation of § 10
    of the Rivers and Harbors Appropriation Act of 1899 (RHA),
    33 U.S.C. § 403; and (3) violation of § 301(a) of the Clean
    Water Act (CWA), 33 U.S.C. § 1311(a).4 The Lummi Nation
    intervened in the consolidated action to assert its interest as
    the beneficial owner of the tidelands.
    In a series of partial summary judgment rulings, District
    Judge Rothstein held that (1) the tidelands were owned by the
    United States, not the state of Washington; (2) the erosion of
    the Homeowners’ property was not caused by an avulsive
    event inundating the uplands;5 and (3) the tideland boundary
    3
    Further complicating matters is the fact that the extent of the shore
    changes seasonally, though mean high water stays relatively constant.
    4
    Although the United States originally sued six landowners, the govern-
    ment and the Lummi Nation reached a settlement with one landowner and
    entered into a consent decree with another.
    5
    Under the doctrine of avulsion, a sudden and abrupt change in the
    shoreline—an avulsive event—does not alter the boundary line. New Jer-
    UNITED STATES v. NICHOLSON                     14467
    line was ambulatory and was not arrested by the Homeown-
    ers’ shore defense structures, so that it lay where the MHW
    line would be located but for the Homeowners’ structures.
    Judge Rothstein then ruled on summary judgment that the
    Homeowners were liable for trespass and violation of the
    RHA, and that the Nicholsons had violated the CWA.
    Although the United States had sued the other Homeowners
    for violation of the CWA, it later dismissed those claims
    against all but the Nicholsons.
    After finding liability, Judge Rothstein imposed an injunc-
    tion under the RHA ordering the Homeowners to remove any
    shore defense structures located seaward of the MHW line.
    District Judge Leighton subsequently conducted a bench trial
    to determine what penalties to impose on the Nicholsons for
    the CWA violation. He imposed a $1500 fine—far less than
    what the government sought—and ordered them to remove rip
    rap below a certain point. Additionally, Judge Leighton heard
    the Milners’ and Bennett/Boyd’s motion for attorneys’ fees
    under the Equal Access to Justice Act (EAJA), 28 U.S.C.
    § 2412, which he denied.
    The Homeowners timely appealed, challenging the sum-
    mary judgment rulings on the trespass, RHA, and CWA
    claims, as well as the injunctive relief imposed by the district
    court. The Homeowners also argue that the district court erred
    in denying the EAJA motion. We address these arguments in
    turn.
    II.
    The district court had jurisdiction over the trespass claims
    under 28 U.S.C. § 1345, the RHA claims under 28 U.S.C.
    sey v. New York, 
    523 U.S. 767
    , 784 (1998); California ex rel. State Lands
    Comm’n v. United States, 
    805 F.2d 857
    , 864 (9th Cir. 1986). The Home-
    owners do not appeal the district court’s ruling that the doctrine of avul-
    sion does not apply.
    14468                UNITED STATES v. NICHOLSON
    §§ 1331, 1345 and 33 U.S.C. § 406, and the CWA claims
    under 28 U.S.C. §§ 1331 and 1345. We have jurisdiction pur-
    suant to 28 U.S.C. § 1291.
    We review the district court’s grant of summary judgment
    de novo. Universal Health Servs., Inc. v. Thompson, 
    363 F.3d 1013
    , 1019 (9th Cir. 2004). We review a district court’s grant
    of injunctive relief for abuse of discretion and will reverse if
    the district court based its decision on an erroneous legal stan-
    dard or a clearly erroneous finding of fact. Fortyune v. Ameri-
    can Multi-Cinema, Inc., 
    364 F.3d 1075
    , 1079 (9th Cir. 2004).
    The decision whether to award fees under the EAJA also is
    reviewed for abuse of discretion. United States v. Marolf, 
    277 F.3d 1156
    , 1160 (9th Cir. 2002).
    III.
    A.
    Federal common law governs an action for trespass on
    Indian lands. United States v. Pend Oreille Pub. Util. Dist.
    No. 1, 
    28 F.3d 1544
    , 1549 n.8 (9th Cir. 1994); see also
    Oneida County v. Oneida Indian Nation of New York State,
    
    470 U.S. 226
    , 235-36 (1985). That law generally comports
    with the Restatement of Torts, and in any event, Washington
    law conforms to the Restatement definition of trespass.6 See
    6
    In some instances, “[c]ontroversies governed by federal law do not
    inevitably require resort to uniform federal rules,” and it may be appropri-
    ate to borrow from state law for the rule of decision. California ex rel.
    State Lands Comm’n v. United States, 
    457 U.S. 273
    , 283 (1982). For
    example, in Wilson v. Omaha Indian Tribe, the Supreme Court held that
    although federal law determined the question of ownership of land contin-
    uously held by the United States for an Indian tribe, state law could be
    borrowed to provide the applicable rules of avulsion and accretion. 
    442 U.S. 653
    , 670-71, 673-74 (1979). While it is clear that the federal common
    law of trespass applies here, it is less clear whether the application of the
    common enemy doctrine, discussed below, should be decided based on a
    uniform federal common law or borrowed Washington state law, which
    UNITED STATES v. NICHOLSON                   14469
    United States v. West, 
    232 F.2d 694
    , 699 (9th Cir. 1956) (cit-
    ing Arizona case law and the Restatement (First) of Torts to
    define trespass); Edwardsen v. Morton, 
    369 F. Supp. 1359
    ,
    1371 (D.D.C. 1973) (applying Restatement (Second) of Torts
    to federal trespass action); United States v. Osterlund, 505 F.
    Supp. 165, 167 (D.C. Colo. 1981) (same); cf. Bradley v. Am.
    Smelting & Ref. Co., 
    709 P.2d 782
    , 785 (Wash. 1985) (quot-
    ing Restatement (Second) of Torts definition of trespass).
    Under the Restatement, a person is liable for trespass “if he
    intentionally . . . causes a thing [to enter land in the posses-
    sion of another], . . . [or] fails to remove from the land a thing
    which he is under a duty to remove.” Restatement (Second)
    of Torts § 158 (2009).
    The district court found it uncontested that portions of the
    Homeowners’ shore defense structures were seaward of the
    MHW line and therefore in Lummi tidelands. Nevertheless,
    the Homeowners make three arguments that they cannot be
    liable for trespass. First, they argue that Washington state, not
    the United States, owns the tidelands; therefore, the United
    States cannot properly assert an action for trespass against
    them. Second, they contend that because their structures were
    lawfully built landward of the MHW line—that is, on the
    Homeowners’ property—they cannot be liable for trespass,
    despite the movement of the tideland boundary. Finally, they
    argue that the elements of intent and causation were not satis-
    fied. We conclude that none of these arguments is correct.
    holds that the doctrine does not apply to sea water. See Grundy v. Thur-
    ston County, 
    117 P.3d 1089
    , 1094 (Wash. 2005). We note that it would
    be anomalous for the Grundy decision to apply to other coastal property
    owners in Washington, yet not to this small group of homeowners. Never-
    theless, we need not decide the issue, because we conclude that the com-
    mon enemy doctrine is inapplicable regardless of whether Grundy
    provides the federal rule of decision.
    14470                UNITED STATES v. NICHOLSON
    1.
    [1] The Homeowners’ ownership argument turns on the
    effect of President Grant’s executive order and its force under
    the “equal footing” doctrine. To put newly admitted states on
    an “equal footing” with the original states, the doctrine creates
    a strong presumption that newly admitted states acquire title
    to lands under navigable waters upon their admission to state-
    hood. Idaho v. United States, 
    533 U.S. 262
    , 272-73 (2001).
    The presumption is rebutted (1) if such lands have been
    reserved by the United States, and (2) if Congress recognizes
    the reservation in a way that demonstrates an intent to rebut
    the presumption. 
    Id. at 273.
    According to the Homeowners,
    because President Grant’s executive order could not perma-
    nently reserve the tidelands for the Lummi, under the equal
    footing doctrine, title passed to the state of Washington when
    it became a state.7
    [2] Prior quiet title actions make clear that President
    Grant’s executive order was sufficient to prevent ownership
    from passing to Washington. In United States v. Romaine, the
    7
    The United States argues that the Homeowners cannot assert Washing-
    ton state’s title in the tidelands because in a trespass action “[t]itle in a
    third person may not be alleged by a defendant who is not in privity of
    title with the third person,” and the Homeowners do not claim to be in
    privity with the state. 75 Am. Jur. 2d Trespass § 62 (2009). However, this
    applies where the plaintiff is the one in possession and, in moving for par-
    tial summary judgment on the issue of ownership, the United States did
    not present evidence showing that it or the Lummi Nation was currently
    in possession of the tidelands. See Thomsen v. State, 
    422 P.2d 824
    , 827
    (Wash. 1966) (“The presumption of the law that the person who has the
    possession has the property may not be rebutted by evidence that the prop-
    erty was in a third person, when offered as a defense by one who claims
    no title and was a wrongdoer.”).
    The United States’ issue preclusion argument is similarly without merit,
    since the prior cases that the government relies on do not involve the
    Homeowners and the Homeowners are not subject to the binding effect of
    the prior judgments. See Taylor v. Sturgell, 
    128 S. Ct. 2161
    , 2172-73
    (2008) (describing the six circumstances in which a nonparty can be
    bound by a prior decision).
    UNITED STATES v. NICHOLSON              14471
    United States sought to quiet title against individuals who had
    bought Lummi tidelands from the state of Washington. 
    255 F. 253
    , 253 (9th Cir. 1919). This court held the president’s exec-
    utive order to be decisive and rejected an argument that the
    reservation extended only to the high-water mark. 
    Id. at 259-
    60. Romaine noted that when Washington was admitted as a
    state, it disclaimed any right and title
    to all lands lying within said limits owned or held by
    any Indian or Indian tribes; and that until the title
    thereto shall have been extinguished by the United
    States, the same shall be and remain subject to the
    disposition of the United States and said Indian lands
    shall remain under the absolute jurisdiction and con-
    trol of the Congress of the United States.
    
    Id. at 260
    (quoting Act of Feb. 22, 1889, ch. 180, § 4, 25 Stat.
    676, 677). United States v. Stotts similarly involved a suit by
    the United States to quiet title in Lummi tidelands purchased
    from the state. 
    49 F.2d 619
    , 619 (W.D. Wash. 1930). Distin-
    guishing United States v. Holt State Bank, 
    270 U.S. 49
    (1926), one of the earliest cases establishing the contours of
    the equal footing doctrine, Stotts held that unlike in Holt the
    Lummi had a specific declaration reserving the tidelands for
    them. 
    Stotts, 49 F.2d at 621
    . Stotts also noted that the Treaty
    of Point Elliott clearly gave the Lummi and other tribes the
    right to fish in their “usual and accustomed grounds and sta-
    tions” and that possession of the tidelands was “a necessary
    perquisite to the enjoyment of fishing.” 
    Id. at 620-21.
    In more
    recent litigation, we again gave effect to the 1873 executive
    order as definitively establishing the boundaries of the Lummi
    reservation, including the order’s reservation of tidelands.
    United States v. Washington, 
    969 F.2d 752
    , 755-56 (9th Cir.
    1992). Notably, in Washington, the state took the position that
    the Lummi reservation extends to the low-tide line and did not
    claim the tidelands. 
    Id. at 753.
    In this lawsuit, the state has
    expressly declined to claim ownership of the tidelands and to
    intervene.
    14472             UNITED STATES v. NICHOLSON
    [3] We have remarked before that stare decisis “applies
    with special force to decisions affecting title to land,” given
    the special reliance that such decisions command. Confeder-
    ated Salish & Kootenai Tribes v. Namen, 
    665 F.2d 951
    , 960
    (9th Cir. 1982); see also Minnesota Co. v. Nat’l Co., 
    70 U.S. 332
    , 334 (1865) (“Where questions arise which affect titles to
    land it is of great importance to the public that when they are
    once decided they should no longer be considered open. Such
    decisions become rules of property, and many titles may be
    injuriously affected by their change.”); Hart v. Massanari,
    
    266 F.3d 1155
    , 1171 (9th Cir. 2001) (“Once a panel resolves
    an issue in a precedential opinion, the matter is deemed
    resolved, unless overruled by the court itself sitting en banc,
    or by the Supreme Court.”). The Lummi and homeowners on
    Sandy Point have long relied on the fact that the Lummi own
    the tidelands. Until 1988, Homeowners leased the tidelands
    from the Lummi, with both sides believing that the Lummi
    owned the tidelands. We see no reason, then, to overturn 90
    years of precedent, especially when the supposed title holder
    has declined to claim ownership.
    Additionally, evaluating the executive order against con-
    temporary case law, we find it sufficient to rebut the presump-
    tion of the equal footing doctrine. As the Supreme Court has
    explained, “the two-step test of congressional intent is satis-
    fied when an Executive reservation clearly includes sub-
    merged lands, and Congress recognizes the reservation in a
    way that demonstrates an intent to defeat state title.” 
    Idaho, 533 U.S. at 273
    (citing United States v. Alaska, 
    521 U.S. 1
    ,
    41-46, 55-61 (1997) (Alaska (Arctic Coast))). Although “dis-
    posals by the United States during the territorial period are not
    lightly to be inferred,” Holt State 
    Bank, 270 U.S. at 55
    ,
    because the two-step test of congressional intent is met, the
    tidelands did not pass to Washington upon its admission to
    statehood.
    [4] The first part of the test is easily met. Article VII of the
    Treaty of Point Elliott provides that “[t]he President may
    UNITED STATES v. NICHOLSON                        14473
    hereafter, when in his opinion the interests of the Territory
    shall require and the welfare of the said Indians be promoted,
    remove them from either or all of the special reservations
    hereinbefore made to the said general reservation, or such
    other suitable place within said Territory as he may deem fit.”
    12 Stat. at 929. Thus, in ratifying the Treaty, Congress gave
    the President the discretionary power to alter the boundaries
    of the reservation;8 he later exercised these powers by explic-
    itly extending the reservation to the low-water mark, thereby
    including the tidelands. Cf. Alaska v. United States, 
    545 U.S. 75
    , 101-02 (2005) (Alaska (Glacier Bay)) (finding that execu-
    tive proclamation reserving submerged lands as part of
    national monument met first prong of congressional intent
    test).
    [5] When Congress admitted Washington to statehood, it
    was aware that the President’s executive order added the tide-
    lands to the reservation. See Alaska (Arctic 
    Coast), 521 U.S. at 45
    (finding that the President’s executive order “placed
    Congress on notice that the President had construed his reser-
    vation authority to extend to submerged lands and had exer-
    cised that authority to set aside uplands and submerged lands
    in the Reserve”). And while Congress admitted Washington
    on an equal footing, 25 Stat. at 679, it also recognized the
    validity of the executive order reservation by requiring Wash-
    8
    Treaties and other agreements with Indians are liberally construed in
    favor of the Indians. Choctaw Nation v. United States, 
    318 U.S. 423
    , 431-
    32 (1943) (“Of course treaties are construed more liberally than private
    agreements[ ] . . . . Especially is this true in interpreting treaties and agree-
    ments with Indians; they are to be construed, so far as possible, in the
    sense in which the Indians understood them, and ‘in a spirit which gener-
    ously recognizes the full obligation of this nation to protect the interests
    of a dependent people’ ” (citations omitted)). The President’s power to
    “remove” the tribes from the specified reservations to “such other suitable
    place . . . as he may deem fit” therefore encompasses the power to expand
    the boundaries of the reservation, since the President has the discretion to
    deem an expanded reservation a suitable replacement for the current one
    and “remove” the tribes from the smaller reservation to the expanded one.
    14474             UNITED STATES v. NICHOLSON
    ington state to “forever disclaim all right and title . . . to all
    lands . . . owned or held by any Indian or Indian tribes.” 
    Id. at 677.
    This proviso was written more broadly than Con-
    gress’s specific recognition of ownership over the National
    Petroleum Reserve in Alaska (Arctic Coast), 
    see 521 U.S. at 41-42
    , but a broad congressional statement can still be a clear
    expression of intent. In Alaska (Glacier Bay), the Supreme
    Court held that an exception that prevented the transfer of
    “lands withdrawn or otherwise set apart as refuges or reserva-
    tions for the protection of wildlife” to the state of Alaska was
    a sufficient indication of intent so as to defeat state title to
    submerged lands in the Glacier Bay National 
    Monument. 545 U.S. at 105
    (quoting the Alaska Statehood Act, Pub. L. No.
    85-508, § 6(e), 72 Stat. 339, 341 (1958)). As in Alaska (Gla-
    cier Bay), Congress made it abundantly clear here that Wash-
    ington would not have title to the lands in question, thereby
    satisfying the second step of the congressional intent test.
    [6] Historically, the Lummi and other Pacific Northwest
    tribes have depended heavily on fishing and digging for shell-
    fish as a means of subsistence. See 
    Stotts, 49 F.2d at 620-21
    ;
    Washington v. Wash. State Commercial Passenger Fishing
    Vessel Ass’n, 
    443 U.S. 658
    , 665-67 (1979). President Grant’s
    reservation of the tidelands thus served to promote the tribe’s
    access to fishing and shellfish, and the welfare of the tribe
    more generally. Longstanding precedent has established that
    the tidelands were reserved for the Lummi, and both the tribe
    and others have relied on this understanding for years. But
    even were there no such precedent, the executive order reserv-
    ing the tidelands was promulgated pursuant to congressional
    authority and subsequently recognized by Congress in a way
    that indicates a clear intent to prevent title from passing to the
    state of Washington. We therefore hold that the United States
    owns the tidelands and holds them in trust for the Lummi.
    UNITED STATES v. NICHOLSON                      14475
    2.
    The problem of riparian and littoral property boundaries is
    a recurring and difficult issue. These disputes can be espe-
    cially complicated where the land borders tidal waters,
    because the waters fluctuate dramatically and because private
    title claims often have to be balanced against federal and state
    interests in the ownership and use of the submerged lands. At
    issue in the Homeowners’ second challenge to the trespass
    claim are two competing common law principles. On the one
    hand, courts have long recognized that an owner of riparian
    or littoral property must accept that the property boundary is
    ambulatory, subject to gradual loss or gain depending on the
    whims of the sea.9 See, e.g., County of St. Clair v. Lovingston,
    
    90 U.S. 46
    , 68-69 (1874). On the other hand, the common law
    also supports the owner’s right to build structures upon the
    land to protect against erosion. See, e.g., Cass v. Dicks, 
    44 P. 113
    , 114 (Wash. 1896) (“If a landowner whose lands are
    exposed to inroads of the sea[ ] . . . erects sea walls or dams
    for the protection of his land, and by so doing causes the tide,
    the current, or the waves to flow against the land of his neigh-
    bor . . . [he] is not responsible in damages to the latter, as he
    has done no wrong having acted in self-defense, and having
    a right to protect his land.” (citation omitted)). In this case, the
    Homeowners’ land has eroded away so dramatically that the
    ambulatory tideland boundary has reached and become fixed
    at their shore defense structures. While the Homeowners can-
    not be faulted for wanting to prevent their land from eroding
    away, we conclude that because both the upland and tideland
    owners have a vested right to gains from the ambulation of
    the boundary, the Homeowners cannot permanently fix the
    9
    While the rights and duties of riparian landowners—those with land
    fronting a river or stream—can differ from those of littoral landowners—
    those with property fronting an ocean, sea, or lake—the rules often over-
    lap and sometimes the distinction is elided altogether. See, e.g., Tusher v.
    Gabrielsen, 
    80 Cal. Rptr. 2d 126
    , 146-47 (Ct. App. 1998); Thies v. How-
    land, 
    380 N.W.2d 463
    , 288 n.2 (Mich. 1985); but see In re Opinions of
    the Justices, 
    106 A. 865
    , 868-69 (Me. 1919) (stating that a riparian owner
    may lower a stream so long as the use is reasonable but that a littoral
    owner may not draw down a lake below the natural level).
    14476             UNITED STATES v. NICHOLSON
    property boundary, thereby depriving the Lummi of tidelands
    that they would otherwise gain.
    [7] Under the common law, the boundary between the tide-
    lands and the uplands is ambulatory; that is, it changes when
    the water body shifts course or changes in volume. See Jef-
    feris v. East Omaha Land Co., 
    134 U.S. 178
    , 189 (1890); Cal-
    ifornia ex rel. State Lands Comm’n v. United States, 
    805 F.2d 857
    , 864 (9th Cir. 1986); United States v. Boynton, 
    53 F.2d 297
    , 298 (9th Cir. 1931). The uplands owner loses title in
    favor of the tideland owner—often the state—when land is
    lost to the sea by erosion or submergence. The converse of
    this proposition is that the littoral property owner gains when
    land is gradually added through accretion, the accumulation
    of deposits, or reliction, the exposure of previously sub-
    merged land. See County of St. 
    Clair, 90 U.S. at 68-69
    ; Jef-
    
    feris, 134 U.S. at 189
    ; 65 C.J.S. Navigable Waters § 95
    (2009). These rules date back to Roman times, and have been
    noted in Blackstone’s Commentaries and many other common
    law authorities and cases. See County of St. Clair, 
    90 U.S. 66
    -
    67 (citing inter alia the Institutes of Justinian, the Code Napo-
    leon, and Blackstone’s Commentaries); John M. Gould, A
    Treatise on the Law of Waters 306-08 (3d ed. 1900) (“Land
    formed by alluvion, or the gradual and imperceptible accre-
    tion from the water, and land gained by reliction, or the grad-
    ual and imperceptible recession of the water, belong to the
    owner of the contiguous land to which the addition is made.
    . . . Conversely land gradually encroached upon by navigable
    waters ceases to belong to the former owner.”); 3 Emory
    Washburn, A Treatise on the American Law of Real Property
    75 (6th ed. 1902) (“[T]he boundary line of an owner’s land
    bordering upon the sea varies with the gradual increase or
    diminution of quantity by the addition of alluvion, or by the
    encroachments of the water upon the land, the line of the
    shore varying accordingly.”).
    [8] Importantly, the upland owner’s right to accretions is a
    vested right and “rests in the law of nature.” County of St.
    UNITED STATES v. NICHOLSON               14477
    
    Clair, 90 U.S. at 68
    . It is justified in large part because the
    upland owner’s land is subject to erosion. As the Supreme
    Court stated in County of St. Clair,
    The riparian right to future alluvion is a vested right.
    It is an inherent and essential attribute of the original
    property. The title to the increment rests in the law
    of nature. It is the same with that of the owner of a
    tree to its fruits, and of the owner of flocks and herds
    to their natural increase. The right is a natural, not a
    civil one. The maxim ‘qui sentit onus debet sentire
    commodum’ [‘he who enjoys the benefit ought also
    to bear the burdens’] lies at its foundation. The
    owner takes the chances of injury and of benefit aris-
    ing from the situation of the property. If there be a
    gradual loss, he must bear it; if, a gradual gain, it is
    his.
    
    Id. at 68-69;
    see also Nebraska v. Iowa, 
    143 U.S. 359
    , 360-61
    (1892) (“Every proprietor whose land is thus bounded [by
    water] is subject to loss by the same means which may add
    to his territory; and, as he is without remedy for his loss in
    this way, he cannot be held accountable for his gain.” (quot-
    ing New Orleans v. United States, 35 U.S. (10 Pet.) 662, 717
    (1836))); Bonelli Cattle Co. v. Arizona, 
    414 U.S. 313
    , 326
    (1973) (“Since a riparian owner is subject to losing land by
    erosion beyond his control, he should benefit from any addi-
    tion to his lands by the accretions thereto which are equally
    beyond his control.”), overruled on other grounds by Oregon
    ex rel. State Land Board v. Corvallis Sand & Gravel Co., 
    429 U.S. 363
    (1977).
    [9] By this logic, both the tideland owner and the upland
    owner have a right to an ambulatory boundary, and each has
    a vested right in the potential gains that accrue from the
    movement of the boundary line. The relationship between the
    tideland and upland owners is reciprocal: any loss experi-
    enced by one is a gain made by the other, and it would be
    14478              UNITED STATES v. NICHOLSON
    inherently unfair to the tideland owner to privilege the forces
    of accretion over those of erosion. Indeed, the fairness ratio-
    nale underlying courts’ adoption of the rule of accretion
    assumes that uplands already are subject to erosion for which
    the owner otherwise has no remedy.
    Some courts have justified the rule of accretion by noting
    that it is in the interest of the community that land have an
    owner and be put to “productive use.” See Bd. of Trustees of
    the Internal Improvement Fund v. Medeira Beach Nominee,
    Inc., 
    272 So. 2d 209
    , 213 (Fla. Dist. Ct. App. 1973); Brainard
    v. State, 
    12 S.W.3d 6
    , 18 (Tex. 1999). While this could be
    seen as supporting the notion that dry uplands should be val-
    ued more than tidelands, we decline to hold that the use of
    uplands is inherently more valuable than the use to which
    tidelands can be put. As was already noted, the tidelands have
    played an important role in the Lummi’s traditional way of
    life, and in most other areas, the tidelands are held by the state
    in trust for the public. See Illinois Central R.R. Co. v. Illinois,
    
    146 U.S. 387
    , 436-37 (1892). These interests are substantial,
    and the uses they represent are not obviously less “produc-
    tive.” See Shively v. Bowlby, 
    152 U.S. 1
    , 57 (1894) (“[Lands
    under tide waters] are of great value to the public for the pur-
    poses of commerce, navigation, and fishery. Their improve-
    ment by individuals, when permitted, is incidental or
    subordinate to the public use and right.”). Thus, both the
    Lummi and the Homeowners must accept that the ambulatory
    boundary is “an inherent and essential attribute of the original
    property,” County of St. 
    Clair, 90 U.S. at 68
    , and that both the
    tidelands and the uplands are subject to diminishment and
    expansion based on the forces of the sea.
    [10] The Homeowners concede that the tideland boundary
    is ambulatory, but only to a point. According to the Home-
    owners, once the MHW line intersects the face of their
    defense structures, the boundary becomes fixed and remains
    so unless the tide line overtops the structures or recedes. The
    Homeowners rightly note that the common law permits them
    UNITED STATES v. NICHOLSON                      14479
    to erect shore defense structures on their property to prevent
    erosion. They contend that they lawfully did just that, build-
    ing landward of the MHW line, and cannot be liable for the
    movement of the tideland boundary. In particular, the Home-
    owners draw support for their position from the common
    enemy doctrine, which provides that “[a] man may raise an
    embankment on his own property to prevent the encroach-
    ments of the sea, although the fact of his doing so may be to
    cause the water to beat with violence against the adjoining
    lands, thereby rendering it necessary for the adjoining land-
    owner to enlarge or strengthen his defenses.” Revell v. People,
    
    52 N.E. 1052
    , 1059 (Ill. 1898) (quotation marks and citation
    omitted).
    [11] Typically, the common enemy doctrine applies as a
    defense to nuisance or trespass actions where a property
    owner has caused surface waters—the “common enemy” of
    all landowners—to invade a neighbor’s property.10 See, e.g.,
    Cass v. Dicks, 
    44 P. 113
    , 114 (Wash. 1896) (“[S]urface water,
    caused by the falling of rain or the melting of snow, and that
    escaping from running streams and rivers, is regarded as an
    10
    Many jurisdictions have dispensed with the doctrine altogether and
    instead apply a rule of reasonableness, under which “each possessor is
    legally privileged to make a reasonable use of his land, even though the
    flow of surface waters is altered thereby and causes some harm to others,
    but incurs liability when his harmful interference with the flow of surface
    waters is unreasonable.” Armstrong v. Francis Corp., 
    120 A.2d 4
    , 8 (N.J.
    1956); see, e.g., Weinberg v. N. Alaska Dev. Corp., 
    384 P.2d 450
    , 452
    (Alaska 1963); Bunch v. Coachella Valley Water Dist., 
    935 P.2d 796
    , 801
    (Cal. 1997); Rodrigues v. State, 
    472 P.2d 509
    , 516 (Haw. 1970); see gen-
    erally, Wendy B. Davis, Reasonable Use Has Become the Common
    Enemy, 9 Alb. L. Envtl. Outlook J. 1, 9-10 (2004) (noting that 21 states
    have adopted the “reasonable use” rule). While Washington has retained
    the doctrine, it has modified the rule so that property owners must exercise
    due care by “acting in good faith and avoiding unnecessary damage to the
    property of others,” Currens v. Sleek, 
    983 P.2d 626
    , 629-30 (Wash. 1999),
    and by making the rule inapplicable to sea water. 
    Grundy, 117 P.3d at 1094
    . It is far from clear, then, that the common enemy rule, as advocated
    by the Homeowners, is even the dominant view.
    14480             UNITED STATES v. NICHOLSON
    outlaw and a common enemy, against which any one may
    defend himself, even though by doing so injury may result to
    others.”). The doctrine therefore does not apply here. On the
    one hand, the injury complained of is not the diversion of
    water onto the tidelands; rather, it is the physical encroach-
    ment of the shore defense structures themselves. With the
    exception of Revell, which held that a waterfront property
    owner had no right to erect structures on submerged land
    owned by the 
    state, 52 N.E. at 1060
    , all the cases cited by the
    Homeowners concern disputes over structures diverting
    waters onto a neighbor’s land, not the maintenance of struc-
    tures on the neighbor’s land. See Lamb v. Reclamation Dist.
    No. 108, 
    14 P. 625
    , 626-27 (Cal. 1887); Miller v. Lezerich, 
    49 S.W.2d 404
    , 406 (Tex. 1932). On the other hand, the rule is
    inapposite because the water is not acting as a “common
    enemy” of the parties involved. The tide line is an inherent
    attribute of the properties at issue, since it dictates where the
    tidelands end and the uplands begin. That the boundary is
    ambulatory does not make it a common enemy, since any
    movement seaward or landward is to the benefit of one party
    and the detriment of the other. It is unfortunate that the
    boundary line increasingly has encroached on the Homeown-
    ers’ property, but they cannot claim that the common enemy
    doctrine allows them to fix permanently the tideland bound-
    ary.
    [12] The Homeowners have the right to build on their prop-
    erty and to erect structures to defend against erosion and
    storm damage, but all property owners are subject to limita-
    tions in how they use their property. The Homeowners cannot
    use their land in a way that would harm the Lummi’s interest
    in the neighboring tidelands. Given that the Lummi have a
    vested right to the ambulatory boundary and to the tidelands
    they would gain if the boundary were allowed to ambulate,
    the Homeowners do not have the right to permanently fix the
    property boundary absent consent from the United States or
    the Lummi Nation. The Lummi similarly could not erect
    structures on the tidelands that would permanently fix the
    UNITED STATES v. NICHOLSON                      14481
    boundary and prevent accretion benefitting the Homeowners.
    Although the shore defense structures may have been legal as
    they were initially erected, this is not a defense against the
    trespass action nor does it justify denying the Lummi land that
    would otherwise accrue to them.
    [13] We emphasize that this does not mean property own-
    ers cannot erect shore defense structures on their property or
    take other action to prevent erosion. Nor does it mean that the
    Homeowners must necessarily remove their structures, if they
    can reach an agreement with the Lummi Nation and the
    United States that allows the structures to remain. Rather, we
    hold only that the Homeowners have no defense to a trespass
    action because they are seeking to protect against erosion.11
    Once the shore has eroded so dramatically that the property
    owner’s shore defense structures fix the ambulatory boundary,
    the upland owner cannot expect to permanently maintain the
    boundary there without paying damages to the tideland owner
    or working out an agreement with the tideland owner. Home-
    owners on Sandy Point previously had leased the tidelands
    from the Lummi, and there is no reason the Homeowners
    could not similarly seek to negotiate a new agreement now.
    11
    Amicus curiae Building Industry Legal Defense Foundation (“BILD”)
    argues that such a rule will have dramatically harmful consequences,
    given the many coastal properties with shore defense structures. This over-
    estimates the reach of our opinion, however. Because of the equal footing
    doctrine and the Submerged Lands Act, 43 U.S.C. § 1311, the states hold
    title to most of the tidelands. Most disputes that arise between the states
    and littoral property owners over tideland boundaries and the use of tide-
    lands are ultimately a matter for state courts to adjudicate under state law.
    The states, of course, must consider the public interest—not just those of
    waterfront property owners—in deciding how to manage their tidelands,
    as they already have been doing. As with many property disputes, those
    between tideland holders and littoral property owners will not be easy to
    resolve and they may simply require the parties to compromise, even if
    that means not everyone is entirely satisfied with the results.
    14482             UNITED STATES v. NICHOLSON
    3.
    It is undisputed that as of the 2002 survey, some of the
    Homeowners’ shore defense structures sat seaward of the
    MHW line. The Homeowners nevertheless argue that they
    cannot be liable for trespass because they did not intend the
    structures to trespass and because the trespass was caused by
    the erosion of the shore and resulting movement of the bound-
    ary, not by the Homeowners.
    [14] However, as the district court noted, to be liable for
    trespass, the Homeowners need not have intended the actual
    trespass. Rather, the intent requirement is satisfied because
    the government requested that the encroaching parts of the
    structures be removed, but the Homeowners failed to do so.
    See New York State Energy Research & Dev. Auth. v. Nuclear
    Fuel Servs., Inc., 
    561 F. Supp. 954
    , 974 (W.D.N.Y. 1983)
    (“In the case of trespass through the continuing presence of
    chattels on another’s land, the requisite intent does not arise
    until the duty to remove the chattels arises, which does not
    occur until a demand for removal has been made.”); see also
    Restatement (Second) of Torts § 161; 75 Am. Jur. 2d Trespass
    § 19 (2009) (“A trespass may be committed by the continued
    presence on the land of a structure, chattel, or other thing that
    the actor or a predecessor in legal interest has placed on the
    land and failed to remove.”). And although the Homeowners
    did not cause the movement of the boundary line, they can
    still be liable for the structures even after the boundary moved
    across the structures. It is enough that the Homeowners
    caused the structures to be erected and that the structures sub-
    sequently rested on the tidelands. See Restatement (Second)
    of Torts § 161, cmts. b, e.
    [15] Given that the United States, not Washington, holds
    title to the tidelands and that the Homeowners cannot perma-
    nently fix the tideland boundary, it quickly follows that the
    Homeowners are liable for trespass. The district court was
    UNITED STATES v. NICHOLSON               14483
    correct, then, in finding in favor of the United States and
    Lummi Nation as to the trespass claim.
    B.
    [16] Turning next to the RHA claim, there are three ways
    in which a defendant could violate § 10 of the RHA. The first
    clause of § 10 prohibits the creation of “any obstruction not
    affirmatively authorized by Congress[ ] to the navigable
    capacity of any of the waters of the United States.” 33 U.S.C.
    § 403. Clauses two and three respectively make it unlawful to
    “build or commence the building of any wharf, pier, dolphin,
    boom, weir, breakwater, bulkhead, jetty, or other structures in
    any port, roadstead, haven, harbor, canal, navigable river, or
    other water of the United States . . . except on plans recom-
    mended by the Chief of Engineers and authorized by the Sec-
    retary of the Army” or to “excavate or fill, or in any manner
    to alter or modify the course, location, condition, or capacity
    of . . . the channel of any navigable water of the United States,
    unless the work has been recommended by the Chief of Engi-
    neers and authorized by the Secretary of the Army prior to
    beginning the same.” 
    Id. Under the
    RHA the navigable waters of the United States
    means “all places covered by the ebb and flow of the tide to
    the mean high water (MHW) mark in its unobstructed, natural
    state.” Leslie Salt Co. v. Froehlke, 
    578 F.2d 742
    , 753 (9th Cir.
    1978); see also 33 C.F.R. §§ 322.2(a), 329.4, 329.12(a)(2).
    Notably, courts have “consistently found [the RHA’s] cover-
    age to be broad,” Wyandotte Transp. Co. v. United States, 
    389 U.S. 191
    , 201 (1967); see also Sanitary Dist. Co. of Chicago
    v. United States, 
    266 U.S. 405
    , 429 (1925) (calling the RHA
    “a broad expression of policy in unmistakable terms”), and
    “read the [RHA] charitably in light of the purpose to be
    served.” United States v. Republic Steel Corp., 
    362 U.S. 482
    ,
    491 (1960).
    The Homeowners concede that they do not have authoriza-
    tion to maintain structures in the navigable waters of the
    14484                UNITED STATES v. NICHOLSON
    United States. Given that at least some of their shore defense
    structures lie seaward of the MHW line, the issue on appeal
    is whether the district court properly ruled that the Homeown-
    ers had violated § 10 by not removing their shore defense
    structures from the tidelands.
    [17] Although § 10 does not explicitly mention the mainte-
    nance of structures in navigable waters, in the sense of keep-
    ing structures in place, we have interpreted the RHA as
    making unlawful the failure to remove structures prohibited
    by § 10, even if they were previously legal. See United States
    v. Alameda Gateway Ltd., 
    213 F.3d 1161
    , 1167 (9th Cir.
    2000) (“Gateway’s assertion that the Corps cannot remove a
    lawfully erected structure is equally unavailing. . . . the RHA
    allows the United States to remove structures that were once
    erected lawfully but subsequently found to be obstructions.”).
    This makes sense in light of the RHA’s concern with insuring
    that navigable waterways remain free of obstruction, because
    even initially legal structures can subsequently interfere with
    navigation. See, e.g., United States v. New York Cent. R.R.,
    
    252 F. Supp. 508
    , 511 (D. Mass. 1965) (finding landward
    remnants of previously legal bridge an obstruction), aff’d per
    curiam, 
    358 F.2d 747
    (1st Cir. 1966). The Homeowners’
    structures may have been legal as initially built, but because
    of the movement of the tidal boundary they now sit in naviga-
    ble waters and are obstructions.12
    [18] The Homeowners argue that Alameda Gateway is
    inapplicable, because it concerns the first clause of § 10, and,
    according to them, the shore defense structures do not inter-
    fere with navigation. However, structures violating clauses
    12
    The Corps’ regulations confirm that structures may be obstructions
    without regard to how the structures came to be in navigable waters. The
    Corps generally requires a permit “for structures and/or work in or affect-
    ing navigable waters,” without reference to whether the structure is being
    initially erected in navigable waters or has already been sitting there. 33
    C.F.R. § 322.3(a).
    UNITED STATES v. NICHOLSON               14485
    two or three are presumed to be obstructions under the first
    clause. Alameda 
    Gateway, 213 F.3d at 1165
    ; Sierra Club v.
    Andrus, 
    610 F.2d 581
    , 596 (9th Cir. 1979), rev’d on other
    grounds sub nom. California v. Sierra Club, 
    451 U.S. 287
    (1981) (holding that there is no implied private right of action
    under § 10 and thus declining to reach the merits). That is,
    clauses two and three have been interpreted as “a legislative
    enumeration of specific obstructions to navigable capacity
    that require Corps authorization” to be legal, 
    Andrus, 610 F.2d at 594
    , with the Corps having discretion to “determine
    what in the particular cases constitute[s] an unreasonable
    obstruction.” 
    Id. at 596
    (quoting Wisconsin v. Illinois, 
    278 U.S. 367
    , 413 (1929)). There is no need, then, for the Corps
    or the courts to determine first that the Homeowners’ struc-
    tures obstruct navigable capacity, since the structures obvi-
    ously qualify as a “breakwater, bulkhead, . . . or other
    structure” under clause two and modify the course, location,
    condition, and capacity of the Strait under clause three. 33
    U.S.C. § 403. The Homeowners are therefore required to have
    Corps authorization; because they have maintained their
    structures in the tidelands without such authorization, they
    can be liable under the RHA.
    BILD argues that under the RHA navigable waters do not
    extend to the MHW line in its “unobstructed, natural state,”
    because Leslie Salt stated that this jurisdictional line “is dic-
    tated by the principle . . . that one who develops areas below
    the MHW line does so at his 
    peril.” 578 F.2d at 753
    . Accord-
    ing to BILD, since the Homeowners claim they built above
    the MHW line, Leslie Salt is inapplicable. On the one hand,
    whether navigable waters reach the MHW in its unobstructed
    state or in its obstructed state is irrelevant here, because the
    Homeowners are liable either way. The topographic survey
    maps submitted by the government show that at least some rip
    rap from the shore defense structures sits below the MHW
    line, and that rip rap has not so obstructed the movement of
    the tide that it is prevented from flowing landward of this
    scattered rip rap. So even assuming an obstruction could pre-
    14486                UNITED STATES v. NICHOLSON
    vent the movement of the MHW line under the RHA, the
    Homeowners have still violated clause two of § 10.
    On the other hand, this argument ignores the RHA’s central
    concern, which is to insure that the nation’s waterways remain
    navigable and free of obstruction. The nation’s navigable
    waterways, of course, can change, and with it the Corps’
    jurisdiction. See, e.g., Swanson v. United States, 
    789 F.2d 1368
    (9th Cir. 1986) (finding Corps had jurisdiction over sub-
    sequently flooded area). Structures that were previously above
    the MHW line can become subject to Corps’ regulation
    because the tide line has moved, and if those structures pre-
    vent the MHW line from achieving its unobstructed, natural
    state they can pose a serious risk to navigation. A structure
    should not be exempt from regulation because it so signifi-
    cantly displaces navigable waters that the waters are perma-
    nently penned in. Just as one who develops below the MHW
    line “does so at his peril,” those who build too close to the
    MHW line also run the risk that their structures eventually
    may become obstructions and be subject to regulation by the
    Corps.13
    [19] The Homeowners’ structures additionally violate
    clause three of § 10, without regard to whether or not one
    considers the waters in their unobstructed state. In certain cir-
    cumstances a structure or activity can still be a violation of
    clauses one or three of § 10 even if the structure or activity
    is not located in navigable waters. See United States v. Sexton
    Cove Estates, Inc., 
    526 F.2d 1293
    , 1298 (5th Cir. 1976). As
    the Fifth Circuit has put it, for the most part § 10 has “no
    locality assigned to its prohibitions.” 
    Id. 13 As
    in Leslie Salt, we express no opinion as to whether or at what point
    the government may be estopped from asserting its jurisdiction because
    land has long ago been filled in, as was the case in United States v. Stoeco
    Homes, Inc., 
    498 F.2d 597
    , 610-11 (3d Cir. 1974). 
    See 578 F.2d at 753
    .
    There is no indication here that the United States excessively delayed its
    enforcement efforts.
    UNITED STATES v. NICHOLSON              14487
    It prohibits any obstruction to navigable capacity.
    There is no suggestion that an obstruction whose
    source is above [the MHW line] escapes prosecution.
    It prohibits the alteration or modification of the
    course, condition, location or capacity of a navigable
    water. There is not the slightest intimation that an
    alteration or modification whose source is above [the
    MHW line] is any less an alteration or modification.
    There is nothing in the language of the statute nor
    the logic of its implementation which creates this
    barrier beyond which the Corps is ubiquitously pow-
    erless. Indeed, such a limitation would thwart the
    design of the statute.
    
    Id. at 1298-99;
    see also 33 C.F.R. § 322.3(a) (“Structures or
    work outside [the navigable waters of the United States] are
    subject to [§ 10] if these structures or work affect the course,
    location, or condition of the waterbody in such a manner as
    to impact on its navigable capacity.”). Under clause three,
    even though the tide line does not extend past the Homeown-
    ers’ shore defense structures because the Homeowners have
    successfully prevented the Strait from advancing landward,
    the structures “alter or modify the course, location, condition,
    or capacity of” the Strait, since the flow of the waters is lim-
    ited by the structures. 33 U.S.C. § 403. The Homeowners are
    therefore liable on this alternative basis as well.
    [20] Because the Homeowners have maintained at least part
    of their shore defense structures below the MHW line, and
    because the structures alter the course, location, condition, or
    capacity of the Strait, they are required to obtain Corps’
    authorization or face liability. Contrary to the Homeowners’
    claim, they need not have intended to violate the RHA; it is
    sufficient under Alameda Gateway that they intentionally
    erected structures that became obstructions. 
    See 213 F.3d at 1167
    . The district court therefore appropriately found liabil-
    ity, and its imposition of an injunction under § 12 of the RHA,
    33 U.S.C. § 406, was not an abuse of discretion, given the
    14488                 UNITED STATES v. NICHOLSON
    standard for injunctions under § 12. See United States v.
    Stoeco Homes, Inc., 
    498 F.2d 597
    , 611 (3d Cir. 1974) (“No
    balancing of interest or need to show irreparable injury is
    required when an injunction is sought under § 12 to prevent
    erection or seek removal of an unlawful structure.”).
    C.
    [21] The CWA prohibits the discharge of any dredged or
    fill material into “navigable waters” unless authorized by the
    Corps. See 33 U.S.C. §§ 1311, 1344. However, the scope of
    the Corps’ regulatory authority under the CWA and RHA is
    not the same, in part because the definition of “navigable
    waters” is broader under the CWA and encompasses all “wa-
    ters of the United States.” 33 U.S.C. § 1362(7); Leslie 
    Salt, 578 F.2d at 754-55
    . Instead of using the MHW line, the
    Corps’ regulations define its CWA jurisdiction over tidal
    waters by reference to the “high tide line,” 33 C.F.R.
    § 328.4(b)(1), which, in turn, is defined as “the line of inter-
    section of the land with the water’s surface at the maximum
    height reached by a rising tide.”14 33 C.F.R. § 328.3(d).
    The district court found on summary judgment that the
    Nicholsons had violated the CWA, because, in the course of
    reconstructing their shore defense structures, they discharged
    fill material below where the high tide line would fall in its
    14
    Locally, the policy of the Seattle District of the Corps has been to
    draw the high tide line at the mean higher high water (MHHW) line,
    which is calculated by averaging over 18.6 years the highest of the two
    high tides that occur in a day and projecting that line onto the shore. Leslie
    
    Salt, 878 F.2d at 746
    . Because the two daily Pacific coast tidal cycles can
    vary greatly in height, the difference between the MHHW line and the
    MHW line—the average of both high tides occurring in a day—can be rel-
    atively large on the west coast of the United States. 
    Id. In fashioning
    a
    remedy for the CWA violation, Judge Leighton took the Corps’ local
    enforcement policy into account, but, contrary to the government’s posi-
    tion, this does not necessarily conflict with what Judge Rothstein found on
    summary judgment.
    UNITED STATES v. NICHOLSON               14489
    unobstructed, natural state without a permit. In so ruling, the
    district court again relied on the holding from Leslie Salt that
    “the MHW line is to be fixed in accordance with its natural,
    unobstructed 
    state.” 578 F.2d at 753
    . However, while Leslie
    Salt applied this rule to the definition of navigable waters
    under the RHA, it was more circumspect as to what the limits
    of navigable waters and the Corps’ jurisdiction are under the
    CWA. The district court in Leslie Salt had held that navigable
    waters under the CWA extended to the MHHW line in its
    unobstructed, natural state. Sierra Club v. Leslie Salt Co., 
    412 F. Supp. 1096
    , 1103 (N.D. Cal. 1976). But we declined to
    hold that the waters of the United States extended to all places
    the water would theoretically reach, partially out of concerns
    that such a ruling swept too broadly and unnecessarily
    included “fast land” or “improved solid upland.” See Leslie
    
    Salt, 578 F.2d at 754
    . Since we could decide Leslie Salt by
    addressing only whether the particular waters in question
    were subject to regulation by the Corps, we did not address
    the ultimate question of what constitutes the outer limit of the
    Corps’ CWA jurisdiction. 
    Id. at 756.
    [22] This case presents more squarely the question of how
    far the Corps’ CWA jurisdiction extends. Leslie Salt
    addressed whether certain waters diked off from the San Fran-
    cisco Bay constituted waters of the United 
    States. 578 F.2d at 756
    . Here there is a question as to whether any water actually
    reaches the area at issue, and if not, whether it is still subject
    to regulation by the Corps. The parties in Leslie Salt agreed
    that the Corps’ jurisdiction does not extend to property that
    was dry, solid upland as of the date of the passage of the
    CWA. See 
    id. at 754.
    In the same vein, the Corps has stated
    that it does not intend to assert jurisdiction over lands that
    once were submerged but which have been transformed into
    dry land. See 42 Fed. Reg. 37128 (July 19, 1977). While we
    do not purport to decide the full extent of the Corps’ CWA
    regulatory authority, we find this approach persuasive. Any
    discharge on fast land would not actually be in the waters of
    the United States, and it would be potentially unfair to occu-
    14490                UNITED STATES v. NICHOLSON
    pants of such land to hold them to the strictures of the CWA
    if the land has long been dry. Even if land has been main-
    tained as dry through artificial means, if the activity does not
    reach or otherwise have an effect on the waters, excavating,
    filling and other work does not present the kind of threat the
    CWA is meant to regulate.
    [23] This does not mean that fast land cannot subsequently
    become submerged by the waters of the United States. As the
    Corps’ regulations acknowledge, gradual changes to the bed
    of a body of water will change the boundaries of the waters
    of the United States. 33 C.F.R. § 328.5. But if land was dry
    upland at the time the CWA was enacted, it will not be con-
    sidered part of the waters of the United States unless the
    waters actually overtake the land, even if it at one point had
    been submerged before the CWA was enacted or if there have
    been subsequent lawful improvements to the land in its dry
    state.15 In short, in such a situation, the waters of the United
    States are demarcated by the reach of the high tide line, but
    not as it would be in its unobstructed, natural state if the fill
    or obstruction was in place at the time the CWA was enacted
    or if there was a legally authorized filling or improvement
    done after the enactment of the CWA.
    15
    This would not change the fact that waters which were in the past nav-
    igable are still considered such, even if they are no longer navigable in
    fact. See United States v. Appalachian Elec. Power Co., 
    311 U.S. 377
    , 408
    (1940) (“When once found to be navigable, a waterway remains so.”); 33
    C.F.R. § 328.3(a)(1). We also reiterate Leslie Salt’s admonition that the
    full extent of the Corps’ CWA jurisdiction over waters of the United
    States “is in some instances not limited to the MHW or the MHHW line.”
    
    Id. at 742.
    For example, where there are adjacent wetlands or intermittent
    streams, the Corps still has jurisdiction, even though these areas are
    beyond the normal ebb and flow of the tide. See, e.g., United States v. Riv-
    erside Bayview Homes, Inc., 
    474 U.S. 121
    , 139 (1985); United States v.
    Moses, 
    496 F.3d 984
    , 989 (9th Cir. 2007). Additionally, some discharges
    on dry land can be CWA violations. See Leslie 
    Salt, 578 F.2d at 753
    n.12
    (citing United States v. Holland, 
    373 F. Supp. 665
    (M.D.Fla. 1974), as an
    example of a discharge above MHHW line that violated CWA).
    UNITED STATES v. NICHOLSON              14491
    [24] Applying that boundary here, it is unclear from the
    evidence presented at summary judgment whether the high
    tide line actually reached the area where the Nicholsons exca-
    vated and filled. Pictures of the bulkhead reconstruction show
    that the rip-rap revetment seaward of the bulkhead may have
    successfully prevented the tide from reaching the area under
    construction. The construction diagrams show an intent to
    excavate to a depth that would be below the high tide line if
    one ignored the existence of the revetment. But if the revet-
    ment was in place prior to the enactment of the CWA or
    legally built on dry land after the passage of the CWA, then
    it must be considered as it actually exists. While the parties
    seem to agree that the revetment was built in 1982 by the
    Nicholsons’ predecessor in interest, on summary judgment the
    government did not present evidence showing that the revet-
    ment was not lawfully built on dry land beyond the reach of
    the high tide line. There was also no evidence that during the
    reconstruction of the bulkhead, the Nicholsons placed addi-
    tional rip rap seaward of the revetment or that their activities
    otherwise led to the discharge of material below the high tide
    line, as it actually existed. The government therefore did not
    carry its burden of showing that the Nicholsons had violated
    the CWA by discharging material into waters of the United
    States. Accordingly, we reverse the grant of summary judg-
    ment on this claim and remand for further proceedings.
    Although the CWA’s jurisdictional reach is generally
    broader than the RHA’s, the reversal here is explained by the
    RHA’s concern with preventing obstructions, on the one
    hand, and the CWA’s focus on discharges into water, on the
    other. Since the two laws serve different purposes, their regu-
    latory powers will diverge in some circumstances, as is the
    case here. Under the RHA, it is appropriate to ignore an
    obstruction’s ability to stop the flow of navigable water,
    because the purpose of the RHA is precisely to prevent or
    remove obstructions to navigable waters. The Homeowners’
    structures clearly impinge on the capacity of the Strait of
    Georgia and portions of them sit within navigable waters;
    14492                UNITED STATES v. NICHOLSON
    they are therefore obstructions. The CWA, on the other hand,
    is designed to restore and maintain the integrity of the
    nation’s waters, which it does by limiting the discharge of
    pollutants into the waters. See 33 U.S.C. § 1251(a). The Nich-
    olsons’ activities in reconstructing their bulkhead, however,
    would not involve a discharge into waters of the United States
    if conducted solely on fast land. The revetment fronting their
    bulkhead may have prevented the MHHW line from reaching
    the construction work—and thereby prevented a discharge
    into navigable waters—while at the same time obstructing
    those waters. It is perfectly consistent, then, that the Home-
    owners could be liable under the RHA while the Nicholsons
    may not be liable under the CWA.
    D.
    Finally, for the court to award attorney’s fees and costs
    under the EAJA, it must be shown that (1) the party seeking
    fees is the prevailing party; (2) the government has not met
    its burden of showing that its positions were substantially jus-
    tified or that special circumstances make an award unjust; and
    (3) the requested fees and costs are reasonable. See Perez-
    Arellano v. Smith, 
    279 F.3d 791
    , 793 (9th Cir. 2002).
    [25] To be a prevailing party, the party must have received
    an enforceable judgment on the merits or a court-ordered con-
    sent decree. Id.; see Buckhannon Bd. & Care Home, Inc. v. W.
    Va. Dep’t of Health & Human Res., 
    532 U.S. 598
    , 604 (2001)
    (“[E]nforceable judgments on the merits and court-ordered
    consent decrees create the ‘material alteration of the legal
    relationship of the parties’ necessary to permit an award of
    attorney’s fees.” (citation omitted)). The Milners and Ben-
    nett/Boyd stipulated to the government’s dismissal, without
    prejudice,16 of the CWA claims against them. However,
    although a defendant may no longer have a claim pending
    16
    Since the stipulation did not state that the dismissal was with preju-
    dice, it was without prejudice. Fed. R. Civ. Proc. 41(a)(1)(B).
    UNITED STATES v. NICHOLSON               14493
    against him or her upon dismissal, a dismissal without preju-
    dice does not materially alter the legal relationship of the par-
    ties, because the defendant remains subject to the risk of re-
    filing. Oscar v. Alaska Dep’t of Educ. & Early Dev., 
    541 F.3d 978
    , 981 (9th Cir. 2008); Cadkin v. Loose, 
    569 F.3d 1142
    ,
    1149 (9th Cir. 2009). Although Oscar and Cadkin concern
    fee-shifting statutes other than the EAJA, they turn on the
    meaning of the term “prevailing party” and govern our inter-
    pretation here. See 
    Perez-Arellano, 279 F.3d at 794
    (noting
    that Buckhannon “sweeps . . . broadly and its reasoning is per-
    suasively applicable to an award of attorney’s fees under the
    EAJA”); 
    Oscar, 541 F.3d at 981
    (relying on Buckhannon to
    determine whether a defendant is a prevailing party); 
    Cadkin, 569 F.3d at 1149
    (same). We therefore conclude that the Mil-
    ners and Bennett/Boyd are not prevailing parties and are not
    entitled to attorneys’ fees under the EAJA.
    IV.
    Although this particular dispute has been ongoing for some
    years now, for an even longer period of time, the Homeown-
    ers on Sandy Point had an agreement with the Lummi Nation
    to lease the tidelands. This allowed the upland owners to con-
    struct and maintain bulkheads, rip rap, and other shore
    defense structures on the tidelands in order to protect their
    property. The Sandy Point Homeowners had an opportunity to
    renew the lease for an additional 25 years, the maximum lease
    term allowed for Indian trust lands. 25 U.S.C. § 415. Addi-
    tionally, throughout this litigation the Lummi have expressed
    a desire to negotiate a new agreement, and at least before
    commencement of this suit, the United States indicated that its
    concerns would be satisfied if the Homeowners entered into
    agreements with the Lummi.
    This action was avoidable. Perhaps the parties still will be
    able to reach an amicable settlement. However, because the
    Homeowners have so far been unable or unwilling to negoti-
    ate an agreement with the Lummi, we must pass on the merits
    14494            UNITED STATES v. NICHOLSON
    of the dispute. For the reasons set forth above, we affirm the
    district court’s decisions on the trespass and RHA claims, and
    its decision not to grant fees under the EAJA. We find that the
    government did not carry its burden on the CWA claim
    against the Nicholsons; we therefore reverse on that claim.
    Each party is to bear its own costs on appeal.
    AFFIRMED IN PART, REVERSED IN PART, AND
    REMANDED.