VIRGINIA v. MARYLAND on exceptions to report of special master

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VIRGINIA v. MARYLAND
on exceptions to report of special master
No. 129, Orig. Argued October 7, 2003—Decided December 9, 2003
Maryland and Virginia have long disputed control of the Potomac River
(River). Of particular relevance here, Article Seventh of the 1785 Com-
pact between those States provided: “The citizens of each state . . . shall
have full property in the shores of Potowmack river adjoining their
lands, with all emoluments and advantages thereunto belonging, and the
privilege of making and carrying out wharves and other improvements,
so as not to obstruct or injure the navigation of the river.” Because
the 1785 Compact did not determine the boundary line between the
two States, they submitted that question to an arbitration panel, which
ultimately issued a binding award (hereinafter Black-Jenkins Award or
Award) placing the boundary at the low-water mark on the River’s Vir-
ginia shore. Although Maryland was thus granted ownership of the
entire riverbed, Article Fourth of the Award further provided: “Virginia
. . . is entitled not only to full dominion over the soil to [its shore’s]
low-water mark . . . , but has a right to such use of the river beyond the
line of low-water mark as may be necessary to the full enjoyment of
her riparian ownership, without impeding the navigation or otherwise
interfering with the proper use of it by Maryland.” Congress approved
both the 1785 Compact and the Black-Jenkins Award pursuant to the
Compact Clause of the Constitution. In 1933, Maryland established a
permitting system for water withdrawal and waterway construction
within her territory. For approximately 40 years, she issued, without
objection, each of the numerous such permits requested by Virginia enti-
ties. The Maryland Department of the Environment (MDE) first de-
nied such a permit when, in 1996, the Fairfax County, Va., Water Au-
thority sought permission to construct a water intake structure, which
would extend 725 feet from the Virginia shore above the River’s tidal
reach and was designed to improve water quality for county residents.
Maryland officials opposed the project on the ground that it would harm
Maryland’s interests by facilitating urban sprawl in Virginia, and the
MDE held that Virginia had not demonstrated a sufficient need for the
offshore intake. Virginia pursued MDE administrative appeals for
more than two years, arguing unsuccessfully at each stage that she was
entitled to build the water intake structure under the 1785 Compact and
the Black-Jenkins Award. Finally, Virginia brought this original action
seeking a declaratory judgment that Maryland may not require Virginia,

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her governmental subdivisions, or her citizens to obtain a permit in
order to construct improvements appurtenant to her shore or to with-
draw water from the River. The Court referred the action to a Special
Master, who issued a Report that, inter alia, concluded that the 1785
Compact and the Black-Jenkins Award gave Virginia the right to use
the River beyond the low-water mark as necessary to the full enjoyment
of her riparian rights; found no support in either of those documents for
Maryland’s claimed sovereign authority over Virginia’s exercise of her
riparian rights; rejected Maryland’s argument that Virginia had lost her
rights of waterway construction and water withdrawal by acquiescing
in Maryland’s regulation of activities on the River; and recommended
that the relief sought by Virginia be granted. Maryland filed excep-
tions to the Report.
Held:
1. The Black-Jenkins Award gives Virginia sovereign authority, free
from regulation by Maryland, to build improvements appurtenant to her
shore and to withdraw water from the River, subject to the constraints
of federal common law and the Award. Article Fourth of the Award
and Article Seventh of the 1785 Compact govern this controversy. The
plain language of the latter grants the “citizens of each state” “full prop-
erty” rights in the “shores of Potowmack river” and the “privilege” of
building “improvements” from the shore. The notable absence of any
grant or recognition of sovereign authority to regulate the exercise of
this “privilege” of the “citizens of each state” contrasts with Article
Seventh’s second clause, which recognized a right held by the “citizens”
of each State to fish in the River, and with Article Eighth, which sub-
jects that right to mutually agreed-upon regulation by the States.
These differing approaches to rights indicate that the 1785 Compact’s
drafters carefully delineated the instances in which the citizens of one
State would be subjected to the regulatory authority of the other.
Other portions of the 1785 Compact also reflect this design. If any
inference is to be drawn from Article Seventh’s silence on the subject
of regulatory authority, it is that each State was left to regulate the
activities of her own citizens. The Court rejects the historical premise
underlying the argument that Article Seventh’s regulatory silence must
be read in Maryland’s favor because her sovereignty over the River was
“well-settled” by the time the 1785 Compact was drafted. The Court’s
own cases recognize that the scope of Maryland’s sovereignty over the
River was in dispute both before and after the 1785 Compact. See,
e. g., Morris v. United States, 174 U. S. 196, 224. The mere existence
of the 1785 Compact further belies Maryland’s argument in that the
compact sought “to regulate and settle the jurisdiction and navigation”

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of the River, 1785–1786 Md. Laws ch. 1 (preamble), an endeavor that
would hardly have been required if, as Maryland claims, her well-settled
sovereignty gave her exclusive authority to regulate all activity on the
River. Accordingly, the Court reads Article Seventh simply to guaran-
tee that each State’s citizens would retain the right to build wharves
and improvements regardless of which State ultimately was determined
to be sovereign over the River. That would not be decided until the
1877 Black-Jenkins Award gave such sovereignty to Maryland. Unlike
the 1785 Compact’s Article Seventh, which concerned the rights of citi-
zens, the plain language of the Award’s Article Fourth gives Virginia,
as a sovereign State, the right to use the River beyond the low-water
mark. Nothing in Article Fourth suggests that Virginia’s rights are
subject to Maryland’s regulation. Indeed, that Article limits Virginia’s
riparian rights only by Maryland’s right of “proper use” and the proviso
that Virginia not “imped[e] . . . navigation,” limitations that hardly
would have been necessary if Maryland retained the authority to regu-
late Virginia’s actions. Maryland’s argument to the contrary is re-
jected, since the States would hardly have submitted to binding arbitra-
tion “for the purpose of ascertaining and fixing the boundary” between
them if that boundary was already well settled. Act of Mar. 3, 1879,
ch. 196, 20 Stat. 481 (preamble). Indeed, the Black-Jenkins arbitrators’
opinion dispels any doubt that sovereignty was in dispute, see, e. g., App.
to Report, p. D–2, and confirms that Virginia’s Article Fourth rights are
sovereign rights not subject to Maryland’s regulation, see id., at D–18
to D–19. Maryland’s necessary concession that Virginia owns the soil
to the low-water mark must also doom her claim that Virginia does not
possess riparian rights to construct improvements beyond that mark
and otherwise make use of the River’s water. The Court rejects Mary-
land’s remaining arguments that the Award merely confirmed the pri-
vate property rights enjoyed by Virginia citizens under the 1785 Com-
pact’s Article Seventh and the common law, which rights are in turn
subject to Maryland’s regulation as sovereign over the River; that the
Award could not have elevated the 1785 Compact’s private property
rights to sovereign rights; and that the requirement under the Award’s
Article Fourth that Virginia exercise her riparian rights on the River
“without impeding the navigation or otherwise interfering with the
proper use of it by Maryland” (emphasis added) indicates Maryland’s
continuing regulatory authority over Virginia’s exercise of her riparian
rights. Also rejected is Justice Kennedy’s conclusion that, because
the Black-Jenkins Opinion rested Virginia’s prescriptive riparian rights
solely on Maryland’s assent to the riparian rights granted private citi-
zens in the 1785 Compact, Maryland may regulate Virginia’s right to

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use the River, so long as Virginia is not excluded from the River alto-
gether. Pp. 65–75.
2. Virginia did not lose her sovereign riparian rights by acquiescing
in Maryland’s regulation of her water withdrawal and waterway con-
struction activities. To succeed in her acquiescence defense, Maryland
must show that Virginia “failed to protest” her assertion of sovereign
authority over waterway construction and water withdrawal. New Jer-
sey v. New York, 523 U. S. 767, 807. Maryland has not carried her bur-
den. As the Special Master found, Virginia vigorously protested Mary-
land’s asserted authority during the negotiations that led to the passage
of § 181 of the Water Resources Development Act of 1976, which re-
quired those States to enter into an agreement with the Secretary of
the Army apportioning the River’s waters during low-flow periods.
Section 181 and the ensuing Low Flow Allocation Agreement are conclu-
sive evidence that, far from acquiescing in Maryland’s regulation, Vir-
ginia explicitly asserted her sovereign riparian rights. Pp. 76–80.
Maryland’s exceptions overruled; relief sought by Virginia granted; and
Special Master’s proposed decree entered.
Rehnquist, C. J., delivered the opinion of the Court, in which O’Con-
nor, Scalia, Souter, Thomas, Ginsburg, and Breyer, JJ., joined.
Stevens, J., filed a dissenting opinion, in which Kennedy, J., joined, post,
p. 80. Kennedy, J., filed a dissenting opinion, in which Stevens, J.,
joined, post, p. 82.
Stuart A. Raphael argued the cause for plaintiff. With
him on the brief were Jerry W. Kilgore, Attorney General of
Virginia, William H. Hurd, Solicitor General, Roger L.
Chaffe and Frederick S. Fisher, Senior Assistant Attorneys
General, and Jill M. Dennis.
Andrew H. Baida, former Solicitor General of Maryland,
argued the cause for defendant. With him on the briefs
were J. Joseph Curran, Jr., Attorney General, and Maureen
Mullen Dove, M. Rosewin Sweeney, Adam D. Snyder, and
Randolph S. Sergent, Assistant Attorneys General.*
*Briefs of amici curiae were filed for the Audubon Naturalist Society by
Kathleen A. Behan and Christopher D. Man; and for the Loudoun County
Sanitation Authority of Virginia by Stanley M. Franklin, E. Duncan Get-
chell, Jr., Robert L. Hodges, and James E. Brown.

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60 VIRGINIA v. MARYLAND
Opinion of the Court
Chief Justice Rehnquist delivered the opinion of the
Court.
Invoking this Court’s original jurisdiction, the Common-
wealth of Virginia seeks a declaration that it has a right to
withdraw water from the Potomac River and to construct
improvements appurtenant to the Virginia shore free from
regulation by the State of Maryland. We granted Virginia
leave to file a complaint, 530 U. S. 1201 (2000), and referred
the action to a Special Master, 531 U. S. 922 (2001). The
Special Master filed a Report recommending that we grant
the relief sought by Virginia. Maryland has filed exceptions
to that Report.
Rising in the Appalachian Highlands of Maryland and
West Virginia, the Potomac River (River) flows nearly 400
miles before emptying into Chesapeake Bay. For the lower
part of its course, it forms the boundary between Maryland
and the District of Columbia on the north, and West Virginia
and Virginia on the south.
Control of the River has been disputed for nearly 400
years. In the 17th century, both Maryland and Virginia laid
claim to the River pursuant to conflicting royal charters is-
sued by different British monarchs. See Maryland v. West
Virginia, 217 U. S. 1, 24–29 (1910); Morris v. United States,
174 U. S. 196, 223–225 (1899).
Virginia traced her claim primarily to the 1609 charter is-
sued by King James I to the London Company, and to a 1688
patent for Virginia’s Northern Neck, issued by King James
II to Lord Thomas Culpeper. West Virginia, supra, at
28–29; Morris, 174 U. S., at 223–224. Both the 1609 charter
and the 1688 patent included the entire Potomac River. Id.,
at 223. Maryland relied on the charter of 1632 from King
Charles I to Lord Baltimore, which also included the Poto-
mac River, although the precise scope of the grant remained
in dispute. West Virginia, supra, at 20, 24–25; Morris,
supra, at 223–225. In her Constitution of 1776, Virginia
ceded ownership of the River to Maryland to the extent the

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River was included in Maryland’s 1632 charter. Va. Const.,
Art. XXI, reprinted in 9 W. Hening’s Statutes at Large 118
(1821). Importantly for our purposes, Virginia specifically
excepted from her cession “the free navigation and use of
the rivers Potowmack and Pocomoke, with the property of
the Virginia shores or strands bordering on either of the
said rivers, and all improvements which have been or shall
be made thereon.” Ibid. In October of that same year,
Maryland passed a resolution at a convention of her constitu-
tional delegates that rejected the reservation in Virginia’s
Constitution. Proceedings of the Conventions of the Prov-
ince of Maryland, held at the City of Annapolis, in 1774, 1775,
1776, pp. 292–293 (J. Lucas & E. Deaver eds. 1836). The
unanimous convention asserted Maryland’s “sole and exclu-
sive jurisdiction” over the River. Ibid.
In the early years of the Republic, “great inconveniences
were experienced by citizens of both Maryland and Virginia
from the want of established and recognized regulations be-
tween those States respecting the jurisdiction and naviga-
tion of the river Potomac.” Wharton v. Wise, 153 U. S. 155,
162 (1894). To address these problems, Maryland and Vir-
ginia appointed commissioners, who, at the invitation of
George Washington, met at Mount Vernon in March 1785.1
Id., at 163; 2 The Diaries of George Washington 1748–1799,
p. 354 (J. Fitzpatrick ed. 1925). The Mount Vernon confer-
ence produced a binding compact (1785 Compact) between
the States, which was subsequently ratified by the Maryland
and Virginia Legislatures. Wharton, supra, at 165–166;
1785–1786 Md. Laws ch. 1; 1785 Va. Acts ch. 17. The 1785
Compact’s 13 articles provided, inter alia, that the River
“shall be considered as a common highway, for the purpose
of navigation and commerce to the citizens of Virginia, and
Maryland” (Article Sixth); that all laws regulating fishing
1 Maryland’s Commissioners were Daniel of St. Thomas Jenifer, Thomas
Stone, and Samuel Chase; Virginia was represented by George Mason and
Alexander Henderson. 1785–1786 Md. Laws ch. 1 (preamble).

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and navigation “shall be made with the mutual consent and
approbation of both states” (Article Eighth); and that juris-
diction over criminal offenses shall be determined based on
the citizenship of the offender and the victim (Article Tenth).
Va. Code Ann. Compacts App., pp. 342–343 (Lexis 2001). Of
particular relevance to this case, Article Seventh provided:
“The citizens of each state respectively shall have full
property in the shores of Potowmack river adjoining
their lands, with all emoluments and advantages there-
unto belonging, and the privilege of making and carry-
ing out wharves and other improvements, so as not to
obstruct or injure the navigation of the river.” Ibid.
Although the 1785 Compact resolved many important nav-
igational and jurisdictional issues, it did not determine the
boundary line between the States, an issue that was “left . . .
open to long continued disputes.” Marine Railway & Coal
Co. v. United States, 257 U. S. 47, 64 (1921); Morris, supra,
at 224; Rhode Island v. Massachusetts, 12 Pet. 657, 724
(1838). In 1874, Virginia and Maryland submitted the
boundary dispute to binding arbitration before a panel of
“eminent lawyers” composed of Jeremiah S. Black, James B.
Beck, and Charles J. Jenkins. Maryland v. West Virginia,
217 U. S. 577, 579 (1910). On January 16, 1877, the arbitra-
tors issued their award (hereinafter Black-Jenkins Award or
Award), placing the boundary at the low-water mark on the
Virginia shore of the Potomac.2 Although Maryland was
thus granted ownership of the entire bed of the River, Arti-
cle Fourth of the Award further provided:
“Virginia is entitled not only to full dominion over the
soil to low-water mark on the south shore of the Poto-
mac, but has a right to such use of the river beyond the
line of low-water mark as may be necessary to the full
2 The “low-water mark” of a river is defined as “the point to which the
water recedes at its lowest stage.” Black’s Law Dictionary 1586 (7th
ed. 1999).

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enjoyment of her riparian ownership, without impeding
the navigation or otherwise interfering with the proper
use of it by Maryland, agreeably to the compact of sev-
enteen hundred and eighty-five.” Act of Mar. 3, 1879,
ch. 196, 20 Stat. 482 (internal quotation marks omitted).
The Black-Jenkins Award was ratified by the Legislatures of
Maryland and Virginia, 1878 Md. Laws ch. 274; 1878 Va. Acts
ch. 246, and approved by the United States Congress, pursu-
ant to the Compact Clause of the Constitution, Art. I, § 10,
cl. 3; Act of Mar. 3, 1879, ch. 196, 20 Stat. 481. See also
Wharton, 153 U. S., at 172–173. We held that when Con-
gress approved the Black-Jenkins Award it implicitly con-
sented to the 1785 Compact as well. Id., at 173.3
In 1933, Maryland established a permitting system for
water withdrawal and waterway construction taking place
within Maryland territory. 1933 Md. Laws ch. 526, §§ 4, 5
(current version codified at Md. Envir. Code Ann. § 5–501
et seq. (1996)). In 1956, Fairfax County became the first Vir-
ginia municipal corporation to apply for a water withdrawal
permit, seeking leave to withdraw up to 15 million gallons of
water per day. App. to Exceptions of Maryland to Report of
Special Master 196. Maryland granted that permit in 1957.
Between 1957 and 1996, Maryland issued, without objection,
at least 29 water withdrawal permits to Virginia entities.
Id., at 57, 197–205. Since 1968, it has likewise issued numer-
ous waterway construction permits to Virginia entities. Id.,
at 276–280.
In 1996, the Fairfax County Water Authority (FCWA)
sought permits from Maryland for construction of a water
intake structure extending 725 feet from the Virginia shore
above the tidal reach of the Potomac River. The structure
3 Because Maryland and Virginia entered into the 1785 Compact prior
to the adoption of the United States Constitution, Congress had not pre-
viously approved it pursuant to the Constitution’s Compact Clause. See
generally Wharton, 153 U. S., at 165–173.

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64 VIRGINIA v. MARYLAND
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was designed to improve water quality for Fairfax County
residents. Several Maryland officials opposed Virginia’s
construction proposal, arguing that it would harm Mary-
land’s interests by facilitating urban sprawl in Virginia. In
late 1997, the Maryland Department of the Environment
(MDE) refused to issue the permit, holding that Virginia had
not demonstrated a sufficient need for the offshore intake.
This marked the first time Maryland had denied such a per-
mit to a Virginia entity. Virginia pursued MDE administra-
tive appeals for more than two years, arguing at each stage
that it was entitled to build the water intake structure under
the 1785 Compact and the Black-Jenkins Award. In Febru-
ary 2000, Virginia, still lacking a permit, sought leave to file
a bill of complaint in this Court, which we granted on March
30, 2000.4 Ultimately, the MDE’s “Final Decision Maker”
determined that Virginia had demonstrated a sufficient need
for the project. In 2001, Maryland finally issued the permit
to FCWA, but only after the Maryland Legislature attached
a condition to the permit requiring FCWA to place a perma-
nent flow restrictor on the intake pipe to limit the amount of
water that could be withdrawn from the River, 2000 Md.
Laws ch. 557, § 1(b)(2)(ii). See Lodging Accompanying
Reply by Virginia to Maryland’s Exceptions to Report of
Special Master L–336 to L–339 (hereinafter Va. Lodging)
(permit issued to FCWA).
In October 2000, while Virginia’s permit request was pend-
ing, we referred Virginia’s bill of complaint to Special Master
Ralph I. Lancaster, Jr. Virginia sought a declaratory judg-
4 This case marks the second time Virginia sought leave to file an origi-
nal action against Maryland concerning Potomac River rights. See Vir-
ginia v. Maryland, 355 U. S. 269 (1957) (per curiam). In the earlier fray,
the Special Master persuaded the States to settle their dispute. They
entered into a new compact, which superseded the 1785 Compact but spe-
cifically preserved the rights delineated in Article Seventh. See Potomac
River Compact of 1958, 1959 Md. Laws ch. 269; 1959 Va. Acts ch. 28; Pub.
L. 87–783, 76 Stat. 797.

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ment that Maryland may not require Virginia, her govern-
mental subdivisions, or her citizens to obtain a permit in
order to construct improvements appurtenant to her shore
or to withdraw water from the River. Maryland did not
dispute that Virginia had rights to withdraw water and
construct improvements under the 1785 Compact and the
Black-Jenkins Award. Report of the Special Master 12
(hereinafter Report). Rather, Maryland asserted that, as
sovereign over the River to the low-water mark, it was enti-
tled to regulate Virginia’s exercise of these rights.5 Ibid.
Maryland further argued that even if the 1785 Compact and
the Award granted Virginia unrestricted rights of waterway
construction and water withdrawal, Virginia lost those
rights by acquiescing in Maryland’s regulation of activities
on the Potomac.
The Special Master recommended that we grant the relief
sought by Virginia. Interpreting the 1785 Compact and the
Black-Jenkins Award, he concluded that these two docu-
ments not only gave citizens of Virginia the right to con-
struct improvements from their riparian property into the
River, but gave the Commonwealth of Virginia the right to
use the River beyond the low-water mark as necessary to the
full enjoyment of her riparian rights. The Special Master
rejected Maryland’s claimed authority to regulate Virginia’s
exercise of her rights, finding no support for that proposi-
tion in either the 1785 Compact or the Award. Finally, the
Special Master rejected Maryland’s defense of acquiescence
by Virginia.
Maryland filed exceptions to the Report of the Special
Master. We now overrule those exceptions.
Virginia and Maryland agree that Article Seventh of
the 1785 Compact and Article Fourth of the Black-Jenkins
5 Maryland also contended that the 1785 Compact and the Black-Jenkins
Award did not apply to the nontidal portions of the River. The Special
Master rejected that argument, Report 96, and Maryland does not pursue
it before this Court.

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66 VIRGINIA v. MARYLAND
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Award govern the instant controversy. Determining
whether Virginia’s rights are subject to Maryland’s regula-
tory authority obviously requires resort to those documents.
We interpret a congressionally approved interstate compact
“[j]ust as if [we] were addressing a federal statute.” New
Jersey v. New York, 523 U. S. 767, 811 (1998); see also ibid.
(“[C]ongressional consent ‘transforms an interstate compact
. . . into a law of the United States’ ” (quoting Cuyler v.
Adams, 449 U. S. 433, 438 (1981))). Article Seventh of the
1785 Compact provides:
“The citizens of each state respectively shall have full
property in the shores of Potowmack river adjoining
their lands, with all emoluments and advantages there-
unto belonging, and the privilege of making and carry-
ing out wharves and other improvements, so as not to
obstruct or injure the navigation of the river.” Va.
Code Ann. Compacts App., pp. 342–343.
The plain language of Article Seventh thus grants to the “cit-
izens of each state” “full property” rights in the “shores of
Potowmack river” and the “privilege” of building “improve-
ments” from the shore. Notably absent is any grant or rec-
ognition of sovereign authority to regulate the exercise of
this “privilege” of the “citizens of each state.” The lack of
such a grant of regulatory authority in the first clause of
Article Seventh contrasts with the second clause of Article
Seventh and Article Eighth, which also recognized a right
held by the “citizens” of each State:
“[T]he right of fishing in the river shall be common to,
and equally enjoyed by, the citizens of both states . . . .
Eighth. All laws and regulations which may be neces-
sary for the preservation of fish . . . shall be made with
the mutual consent and approbation of both states.”
Id., at 343.
Thus, while the Article Seventh right to build improvements
was not explicitly subjected to any sovereign regulatory au-

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thority, the fishing right in the same article was subjected to
mutually agreed-upon regulation. We agree with Virginia
that these differing approaches to rights contained in the
same article of the 1785 Compact indicate that the drafters
carefully delineated the instances in which the citizens of one
State would be subject to the regulatory authority of the
other. Other portions of the 1785 Compact reflect this de-
sign. See Article Fourth (providing that certain vessels
“may enter and trade in any part of either state, with a per-
mit from the naval-officer of the district from which such
vessel departs with her cargo . . .”); Article Eighth (provid-
ing for joint regulation of navigation on the River); Article
Ninth (providing for a bistate commission to govern the erec-
tion of “light houses, beacons, buoys, or other signals”). Id.,
at 342–343. If any inference at all is to be drawn from Arti-
cle Seventh’s silence on the subject of regulatory authority,
we think it is that each State was left to regulate the activi-
ties of her own citizens.
Maryland, however, argues that we must read Article Sev-
enth’s regulatory silence in her favor because her sover-
eignty over the River was “well-settled” by the time the
1785 Compact was drafted. Exceptions of Maryland to Re-
port of Special Master 19 (hereinafter Md. Brief). Maryland
is doubtless correct that if her sovereignty over the River
was well settled as of 1785, we would apply a strong pre-
sumption against reading the Compact as stripping her au-
thority to regulate activities on the River. See, e. g., Massa-
chusetts v. New York, 271 U. S. 65, 89 (1926) (“[D]ominion
over navigable waters, and property in the soil under them,
are so identified with the exercise of the sovereign powers
of government that a presumption against their separation
from sovereignty must be indulged”). But we reject Mary-
land’s historical premise.
Each State has produced reams of historical evidence to
support its respective view about the status of sovereignty
over the River as of 1785. We need not delve deeply into

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68 VIRGINIA v. MARYLAND
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this historical record to decide this issue. Our own cases
recognize that the scope of Maryland’s sovereignty over the
River was in dispute both before and after the 1785 Compact.
Morris, upon which Maryland relies, does not support
her argument. Therein, we observed that “[o]wing to the
conflicting descriptions, as respected the Potomac River,
contained in [the] royal grants, a controversy early arose
between Virginia and Maryland.” 174 U. S., at 224. While
the 1785 Compact resolved certain jurisdictional issues,
it did not determine the boundary between the States.
Ibid. Accordingly, the controversy over sovereignty was
“still continuing . . . in 1874.” Ibid. In Marine Railway,
we likewise acknowledged that even after the 1785 Compact,
“the question of boundary” was left “open to long continued
disputes.” 257 U. S., at 64. See also Rhode Island, 12 Pet.,
at 723 (“Maryland and Virginia were contending about
boundaries in 1835 . . . and the dispute is yet an open one [in
1838]”). Morris did ultimately decide that Maryland’s 1632
charter included the Potomac River from shore to shore, 174
U. S., at 225, but this conclusion, reached in 1899, hardly ne-
gates our statements in that and other cases recognizing that
the dispute over the interstate boundary continued well into
the 19th century.
The mere existence of the 1785 Compact further belies
Maryland’s argument. After all, the 1785 Compact sought
“to regulate and settle the jurisdiction and navigation” of
the River. 1785–1786 Md. Laws ch. 1 (preamble). This en-
deavor would hardly have been required if, as Maryland
claims, her well-settled sovereignty gave her exclusive au-
thority to regulate all activity on the River.6 Nowhere is
this more clear than with respect to the Article Seventh
right of Virginia citizens to build improvements from the
Virginia shore. In 1776, Virginia had purported to reserve
6 For example, if Maryland had well-settled exclusive jurisdiction over
the River, it certainly would not have agreed to joint regulation of fishing
as it did in Article Eighth of the 1785 Compact.

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sovereignty over “the property of the Virginia shores or
strands bordering on either of the said rivers, and all im-
provements which have been or shall be made thereon.”
Va. Const., Art. XXI, reprinted in 9 W. Hening’s Statutes at
Large 118. It would be anomalous to conclude that Mary-
land’s sovereign authority to regulate the construction of
such improvements was so well established a mere nine
years later that the 1785 Compact’s drafters did not even
need to mention it.
Accordingly, we read the 1785 Compact in light of the on-
going dispute over sovereignty. Article Seventh simply
guaranteed that the citizens of each State would retain
the right to build wharves and improvements regardless of
which State ultimately was determined to be sovereign over
the River. That would not be decided until the Black-
Jenkins Award of 1877.
The Black-Jenkins arbitrators held that Maryland was sov-
ereign over the River to the low-water mark on the Virginia
shore. See Act of Mar. 3, 1879, ch. 196, 20 Stat. 481–482.
“[I]n further explanation of this award, the arbitrators
deem[ed] it proper to add” four articles, id., at 482, the last
of which provides:
“ ‘Virginia is entitled not only to full dominion over the
soil to low-water mark on the south shore of the Poto-
mac, but has a right to such use of the river beyond the
line of low-water mark as may be necessary to the full
enjoyment of her riparian ownership, without impeding
the navigation or otherwise interfering with the proper
use of it by Maryland, agreeably to the compact of sev-
enteen hundred and eighty-five.’ ” Ibid.
Unlike the 1785 Compact’s Article Seventh, which concerned
the rights of citizens, the plain language of Article Fourth of
the Award gives Virginia, as a sovereign State, the right to
use the River beyond the low-water mark. Nothing in Arti-
cle Fourth suggests that Virginia’s rights are subject to

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70 VIRGINIA v. MARYLAND
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Maryland’s regulation. Indeed, Virginia’s riparian rights
are limited only by Maryland’s right of “proper use” and the
proviso that Virginia not “imped[e] . . . navigation,” limita-
tions that hardly would have been necessary if Maryland re-
tained the authority to regulate Virginia’s actions. Mary-
land argues, however, that the Black-Jenkins Award simply
confirmed her well-settled ownership of the Potomac, and
thus the rights granted to Virginia in Article Fourth are sub-
ject to Maryland’s regulatory authority.
We have already rejected Maryland’s contention that the
extent of her sovereignty over the Potomac was well settled
before the 1785 Compact. Similarly, we fail to see why
Maryland and Virginia would have submitted to binding ar-
bitration “for the purpose of ascertaining and fixing the
boundary” between them if that boundary was already well
settled. Id., at 481 (preamble). Indeed, the opinion issued
by the arbitrators dispels any doubt that sovereignty was in
dispute, and confirms that Virginia’s Article Fourth rights
are sovereign rights not subject to Maryland’s regulation.
At the beginning of their opinion, the arbitrators explained
that their task was to “ascertain what boundaries were as-
signed to Maryland” by her 1632 charter. Black-Jenkins
Opinion (1877), App. to Report, p. D–2. The arbitrators
then outlined the extent of the existing dispute over the
boundary:
“The State of Virginia, through her Commissioners and
other public authorities, adhered for many years to her
claim for a boundary on the left bank of the Potomac.
But the gentlemen who represent her before us ex-
pressed with great candor their own opinion that a true
interpretation of the King’s concession would divide the
river between the States by a line running in the middle
of it. This latter view they urged upon us with all
proper earnestness, and it was opposed with equal zeal
by the counsel for Maryland, who contended that the

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whole river was within the limits of the grant to Lord
Baltimore.” Id., at D–7.
Thus, contrary to Maryland’s assertion, sovereignty over the
River was hotly contested at the time of the arbitration.
We see no reason, therefore, to depart from Article Fourth’s
plain language, which grants to Virginia the sovereign right
to use the River beyond the low-water mark.
The reasoning contained in the Black-Jenkins Opinion con-
firms the plain language of Article Fourth of the Award. Al-
though the arbitrators initially determined that the bound-
ary contained in the 1632 charter was the high-water mark
on the Virginia shore, id., at D–9, they ultimately held that
Virginia had gained ownership by prescription of the soil up
to the low-water mark, id., at D–18. In the same paragraph,
the arbitrators explained that Virginia had a sovereign right
to build improvements appurtenant to her shore:
“The evidence is sufficient to show that Virginia, from
the earliest period of her history, used the South bank
of the Potomac as if the soil to low water-mark had been
her own. She did not give this up by her Constitution
of 1776, when she surrendered other claims within the
charter limits of Maryland; but on the contrary, she ex-
pressly reserved ‘the property of the Virginia shores or
strands bordering on either of said rivers, (Potomac and
Pocomoke,) and all improvements which have or will be
made thereon.’ By the compact of 1785, Maryland as-
sented to this, and declared that ‘the citizens of each
State respectively shall have full property on the shores
of Potomac and adjoining their lands, with all emolu-
ments and advantages thereunto belonging, and the
privilege of making and carrying out wharves and other
improvements.’ . . . Taking all together, we consider
it established that Virginia has a proprietory right on
the south shore to low water-mark, and, appurtenant
thereto, has a privilege to erect any structures con-

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72 VIRGINIA v. MARYLAND
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nected with the shore which may be necessary to the
full enjoyment of her riparian ownership, and which
shall not impede the free navigation or other common
use of the river as a public highway.
“To that extent Virginia has shown her rights on the
river so clearly as to make them indisputable.” Id., at
D–18 to D–19.
The arbitrators did not differentiate between Virginia’s do-
minion over the soil and her right to construct improvements
beyond low-water mark. Indeed, Virginia’s right “to erect
. . . structures connected with the shore” is inseparable from,
and “necessary to,” the “full enjoyment of her riparian own-
ership” of the soil to low-water mark. Ibid. Like her own-
ership of the soil, Virginia gained the waterway construction
right by a long period of prescription. That right was “re-
served” in her 1776 Constitution, “assented to” by Maryland
in the 1785 Compact, and “indisputabl[y]” shown by Virginia.
Ibid. Thus, the right to use the River beyond low-water
mark is a right of Virginia qua sovereign, and was nowhere
made subject to Maryland’s regulatory authority. Mary-
land’s necessary concession that Virginia owns the soil to
low-water mark must also doom her claim that Virginia does
not possess riparian rights appurtenant to those lands to con-
struct improvements beyond the low-water mark and other-
wise make use of the water in the River. 7
7 The sovereign character of Virginia’s Article Fourth riparian rights is
further confirmed by the proposal of Maryland’s representatives before
the arbitrators. Maryland contended that the “true” boundary line
should be drawn around “all wharves and other improvements now ex-
tending or which may hereafter be extended, by authority of Virginia from
the Virginia shore into the [Potomac] beyond low water mark.” Va.
Lodging L–130 (W. Whyte and I. Jones, Boundary Line Between the
States of Maryland and Virginia, Before the Hons. Jeremiah S. Black, Wil-
liam A. Graham, and Charles J. Jenkins, Arbitrators upon the Boundary
Line between the States of Virginia and Maryland (June 26, 1874)). In
proceedings from 1870–1874, in which the States unsuccessfully attempted

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We reject Maryland’s remaining arguments. Maryland,
as well as Justice Stevens, post, at 81 (dissenting opinion),
contends that the Award merely confirmed the private prop-
erty rights enjoyed by Virginia citizens under Article Sev-
enth of the 1785 Compact and the common law, which rights
are in turn subject to Maryland’s regulation as sovereign
over the River. The arbitration proceedings, however, were
convened to “ascertai[n] and fi[x] the boundary” between co-
equal sovereigns, 20 Stat. 481 (preamble), not to adjudicate
the property rights of private citizens. Neither Maryland
nor Justice Stevens provides any reason to believe the
arbitrators were addressing private property rights when
they awarded “Virginia” a right to use the River beyond the
low-water mark. Their interpretation, moreover, renders
Article Fourth duplicative of the 1785 Compact and the com-
mon law (which secured riparian owners’ property rights)
and the rest of the Black-Jenkins Award (which granted
Maryland sovereignty to low-water mark).8 Only by read-
to fix the boundary without the necessity of arbitration, Maryland’s com-
missioners took the same position, which they described as follows:
“The line along the Potomac River is described in our first proposition
according to our construction of the compact of 1785, and as we are in-
formed, is according to the general understanding of the citizens of both
States residing upon or owning lands bordering on the shores of that river,
and also in accordance with the actual claim and exercise of jurisdiction
by the authorities of the two States hitherto.” Id., at L–14 (Report and
Journal of Proceedings of the Joint Commissioners to Adjust the Boundary
Line of the States of Maryland and Virginia 27 (1874)).
Although the arbitrators did not accept Maryland’s proposal to preserve
Virginia’s sovereign right to build improvements by including them within
Virginia’s territory, they accomplished the same result in Article Fourth
of the Award.
8 Similarly, Justice Kennedy does not adequately explain why Article
Fourth—part of a document that grants unrestricted sovereign rights—
would merely “affir[m] that Virginia, as much as its citizens, has riparian
rights under the 1785 Compact,” post, at 87 (dissenting opinion), when
Virginia, as owner of the soil to low-water mark, already possessed such
rights under the common law.

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74 VIRGINIA v. MARYLAND
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ing Article Fourth in accord with its plain language can this
Court give effect to each portion of the Award. See, e. g.,
TRW Inc. v. Andrews, 534 U. S. 19, 31 (2001) (“It is ‘a cardi-
nal principle of statutory construction’ that ‘a statute ought,
upon the whole, to be so construed that, if it can be pre-
vented, no clause, sentence, or word shall be superfluous,
void, or insignificant’ ”) (quoting Duncan v. Walker, 533 U. S.
167, 174 (2001) (some internal quotation marks omitted)).
Relatedly, Maryland argues that the Award could not have
“elevate[d],” Md. Brief 29, the private property rights of the
1785 Compact to sovereign rights because the arbitrators
disclaimed “authority for the construction of this compact,”
Black-Jenkins Opinion (1877), App. to Report, at D–18.
Again, Maryland mischaracterizes the arbitrators’ decision.
In granting Virginia sovereign riparian rights, the arbitra-
tors did not construe or alter any private rights under the
1785 Compact; rather, they held that Virginia had gained
sovereign rights by prescription.
Finally, Maryland notes that under Article Fourth of the
Award, Virginia must exercise her riparian rights on the
River “ ‘without impeding the navigation or otherwise inter-
fering with the proper use of it by Maryland . . . .’ ” 20
Stat. 482 (emphasis added). Maryland suggests that this
language indicates her continuing regulatory authority over
Virginia’s exercise of her riparian rights. This seems to us
a strained reading. The far more natural reading accords
with the plain language of the Award and opinion: Maryland
and Virginia each has a sovereign right to build improve-
ments appurtenant to her own shore and to withdraw water,
without interfering with the “proper use of ” the River by
the other.9
9 Federal common law governs interstate bodies of water, ensuring that
the water is equitably apportioned between the States and that neither
State harms the other’s interest in the river. See, e. g., Colorado v. New
Mexico, 459 U. S. 176, 183 (1982) (“Equitable apportionment is the doctrine

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Justice Kennedy, while acknowledging that Virginia has
a right to use the River, argues that Maryland may regulate
Virginia’s riparian usage so long as she does not exclude Vir-
ginia from the River altogether. Post, p. 82 (dissenting
opinion). To reach this conclusion, he reasons that the
Black-Jenkins Opinion rested Virginia’s prescriptive riparian
rights solely on Maryland’s assent to the riparian rights
granted to private citizens in the 1785 Compact. Post, at
87–89. According to Justice Kennedy, therefore, “Virgin-
ia’s claims under Black-Jenkins rise as high as the Compact
but no higher.” Post, at 89.
We have already held that the Award’s plain language per-
mits no inference of Maryland’s regulatory authority, supra,
at 69–70; we also disagree that the arbitrators relied solely
on the 1785 Compact as support for Virginia’s prescriptive
rights. To the contrary, the arbitrators’ opinion also relied
upon Virginia’s riparian usage “from the earliest period of
her history” and her express reservation in her 1776 Consti-
tution of the unrestricted right to build improvements from
the Virginia shore. Black-Jenkins Opinion (1877), App. to
Report, at D–18. Indeed, since the arbitrators disclaimed
“authority for the construction of [the 1785] compact . . . be-
cause nothing which concern[ed] it” was before them, ibid.,
it would be anomalous to conclude that Virginia’s “sole right”
under the Award “stem[s] from,” and is “delimited” by,
Article Seventh of the Compact. Post, at 90 (Kennedy, J.,
dissenting).
Accordingly, we conclude that the Black-Jenkins Award
gives Virginia sovereign authority, free from regulation by
Maryland, to build improvements appurtenant to her shore
and to withdraw water from the River, subject to the con-
straints of federal common law and the Award.
of federal common law that governs the disputes between States concern-
ing their rights to use the water of an interstate stream”).

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76 VIRGINIA v. MARYLAND
Opinion of the Court
We next consider whether Virginia has lost her sovereign
riparian rights by acquiescing in Maryland’s regulation of
her water withdrawal and waterway construction activities.
We recently considered in depth the “affirmative defense of
prescription and acquiescence” in New Jersey, 523 U. S., at
807. To succeed in her defense, Maryland must “ ‘show by
a preponderance of the evidence . . . a long and continuous
. . . assertion of sovereignty over’ ” Virginia’s riparian activi-
ties, as well as Virginia’s acquiescence in her prescriptive
acts. Id., at 787 (quoting Illinois v. Kentucky, 500 U. S. 380,
384 (1991)). Maryland has not carried her burden.
Although “we have never established a minimum period of
prescription” necessary for one State to prevail over a co-
equal sovereign on a claim of prescription and acquiescence,
New Jersey, 523 U. S., at 789, we have noted that the period
must be “substantial,” id., at 786. Maryland asserts that in
the 125 years since the Black-Jenkins Award, Virginia has
acquiesced in her pervasive exercise of police power over
activities occurring on piers and wharves beyond the low-
water mark. Among other things, Maryland claims, and
Virginia does not dispute, that it has taxed structures
erected on such improvements (i. e., restaurants, etc.); issued
licenses for activities occurring thereon (i. e., liquor, gam-
bling, etc.); and exercised exclusive criminal jurisdiction over
crimes occurring on such improvements beyond the low-
water mark. We agree with the Special Master that this
evidence has little or no bearing on the narrower question
whether Virginia acquiesced in Maryland’s efforts to reg-
ulate her right to construct the improvements in the first
instance and to withdraw water from the River. See Re-
port 79–82. With respect to Maryland’s regulation of these
particular rights, the claimed prescriptive period is much
shorter.
It is undisputed that Maryland issued her first water with-
drawal permit to a Virginia entity in March 1957 and her
first waterway construction permit in April 1968. The pre-

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Opinion of the Court
scriptive period ended, at the latest, in February 2000, when
Virginia sought leave to file a bill of complaint in this Court.
Accordingly, Maryland has asserted a right to regulate Vir-
ginia’s water withdrawal for, at most, 43 years, and a right to
regulate waterway construction for, at most, 32 years. Only
once before have we deemed such a short period of time
sufficient to prove prescription in a case involving our origi-
nal jurisdiction. See Nebraska v. Wyoming, 507 U. S. 584,
594–595 (1993) (41 years). In that case, we held that Ne-
braska’s sovereign right to water stored in certain inland
lakes was established by a decree issued in 1945. Id., at 595.
We held, in the alternative, that “Wyoming’s arguments are
foreclosed by its postdecree acquiescence” for 41 years.
Ibid. Here, it is Virginia’s sovereign right that was clearly
established by a prior agreement, and Maryland that seeks
to defeat those rights by showing Virginia’s acquiescence.
Under these circumstances, it is far from clear that such a
short prescriptive period is sufficient as a matter of law.
Cf. New Jersey, 523 U. S., at 789 (noting that a prescriptive
period of 64 years is “not insufficient as a matter of general
law”). But even assuming such a short prescriptive period
would be adequate to overcome a sovereign right granted in
a federally approved interstate compact, Maryland’s claim
fails because it has not proved Virginia’s acquiescence.
To succeed on the acquiescence prong of her defense,
Maryland must show that Virginia “failed to protest” her as-
sertion of sovereign authority over waterway construction
and water withdrawal. Id., at 807.10 As the Special Master
found, however, Virginia vigorously protested Maryland’s as-
serted authority during the negotiations that led to the pas-
sage of § 181 of the Water Resources Development Act of
1976 (WRDA), 90 Stat. 2939–2940, codified at 42 U. S. C.
§ 1962d–11a.
10 Maryland’s evidence that Virginia has never operated a permitting
system for water withdrawal or waterway construction is insufficient to
satisfy Maryland’s burden. See New Jersey, 523 U. S., at 788, n. 9.

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78 VIRGINIA v. MARYLAND
Opinion of the Court
Section 181 ultimately required Maryland and Virginia to
enter into an agreement with the Secretary of the Army ap-
portioning the waters of the Potomac River during times of
low flow. 90 Stat. 2939–2940. At the outset of negotiations
over § 181, Maryland proposed a draft bill that asserted her
exclusive authority to allocate water from the Potomac.
Virginia officials protested Maryland’s proposal in three con-
gressional hearings during the summer of 1976, asserting
Virginia’s unqualified right to withdraw water from the
River, and objecting that Maryland’s bill “ ‘might deprive
Virginia of its riparian rights to the waters of the Potomac
River as guaranteed by the 1785 compact . . . and the arbitra-
tion award of 1877 . . . .’ ” Omnibus Water Resources Devel-
opment Act of 1976: Hearings before the Subcommittee on
Water Resources of the Senate Committee on Public Works,
94th Cong., 2d Sess., 2068 (statement of J. Leo Bourassa)
(Aug. 5, 1976); see also Potomac River: Hearings and Markup
before the Subcommittee on Bicentennial Affairs, the Envi-
ronment, and the International Community, and the House
Committee on the District of Columbia, 94th Cong., 2d Sess.,
680, 693–694, 703 (statement of Earl Shiflet) (June 25, 1976);
Water Resources Development—1976: Hearings before the
Subcommittee on Water Resources of the House Committee
on Public Works and Transportation, 94th Cong., 2d Sess.,
442–446 (statement of Eugene Jensen) (Aug. 31, 1976). As
a result of Virginia’s protest, the final legislation provided
that “nothing in this section shall alter any riparian rights
or other authority of . . . the Commonwealth of Virginia, or
any political subdivision thereof . . . relative to the appropria-
tion of water from, or the use of, the Potomac River.” 42
U. S. C. § 1962d–11a(c). Similarly, nothing in the Low Flow
Allocation Agreement reached by Maryland and Virginia
pursuant to the WRDA suggested that Maryland had author-
ity to regulate Virginia’s riparian rights in the River. Va.
Lodging L–285 to L–309. We hold that § 181 of the WRDA
and the Low Flow Allocation Agreement are conclusive evi-

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Decree
dence that, far from acquiescing in Maryland’s regulation,
Virginia explicitly asserted her sovereign riparian rights.11
* * *
Accordingly, we overrule Maryland’s exceptions to the Re-
port of the Special Master. We grant the relief sought by
Virginia and enter the decree proposed by the Special
Master.
It is so ordered.
DECREE
The Court having exercised original jurisdiction over this
controversy between two sovereign States; the issues raised
having been tried before the Special Master appointed by
the Court; the Court having received briefs and heard oral
argument on the parties’ exceptions to the Report of the
Special Master; and the Court having issued its Opinion on
all issues announced, ante, p. 56.
It is Hereby Ordered, Adjudged, Declared, and Decreed
as follows:
1. Article Seventh of the Compact of 1785 between the
Commonwealth of Virginia and the State of Maryland, which
governs the rights of the Commonwealth of Virginia, its gov-
ernmental subdivisions and its citizens to withdraw water
from the Potomac River and to construct improvements ap-
purtenant to the Virginia shore, applies to the entire length
of the Potomac River, including its nontidal reach.
2. Virginia, its governmental subdivisions, and its citizens
may withdraw water from the Potomac River and construct
improvements appurtenant to the Virginia shore of the Poto-
mac River free of regulation by Maryland.
3. Any conditions attached to the construction/water ap-
propriation permit granted by Maryland to the Fairfax
11 Consequently, we need not discuss other evidence of Virginia’s pro-
tests, which has been ably chronicled by the Special Master. See Re-
port 83–89.

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80 VIRGINIA v. MARYLAND
Stevens, J., dissenting
County Water Authority on January 24, 2001, are null and
void and the State of Maryland is enjoined from enforcing
them.
4. The Court retains jurisdiction to entertain such further
proceedings, enter such orders, and issue such writs as may
from time to time be considered necessary or desirable to
give proper force and effect to this Decree or to effectuate
the rights of the parties.
5. The party States shall share equally in the compensa-
tion of the Special Master and his assistants, and in the ex-
penses of this litigation incurred by the Special Master.
Justice Stevens, with whom Justice Kennedy joins,
dissenting.
The basic facts that should control the disposition of this
case are not in dispute. Maryland owns the water in the
Potomac River to the low-water mark on the river’s southern
shore. Virtually the entire river is located within Maryland.
Maryland is therefore the sovereign that exercises regula-
tory jurisdiction over the river, subject only to the provi-
sions of the Maryland-Virginia Compact of 1785 (1785 Com-
pact)1 and the Virginia and Maryland Boundary Agreement
of 1878 (Black-Jenkins Award),2 and to the authority of the
United States to preserve the river’s navigability and pro-
tect its water quality.
Article Seventh of the 1785 Compact provides that the
“citizens of each state respectively shall have full property
in the shores of Potowmack river adjoining their lands, with
all emoluments and advantages thereunto belonging,” includ-
ing the specific privilege of making wharves and other im-
provements, and a “right of fishing in the river [that] shall
be common to, and equally enjoyed by, the citizens of both
1 1785–1786 Md. Laws ch. 1; 1785 Va. Acts ch. 17.
2 1878 Md. Laws ch. 274; 1878 Va. Acts ch. 246; Act of Mar. 3, 1879,
ch. 196, 20 Stat. 481.

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Stevens, J., dissenting
states . . . .” 3 The 1785 Compact is silent on the subject of
water withdrawals. Nevertheless, the owners of property
abutting the river unquestionably enjoy full riparian rights
as part of the “emoluments and advantages” appurtenant to
their title. Indeed, the Black-Jenkins Award confirms this
understanding; under Article Fourth, Virginia “has a right
to such use of the river beyond the line of low-water mark
as may be necessary to the full enjoyment of her riparian
ownership . . . .” 4
The question for decision, therefore, is simple: Are ripar-
ian landowners’ rights to withdraw water unlimited, or may
they be restricted by the sovereign that owns and controls
the adjacent water body (in this case, Maryland)? In my
opinion—an opinion apparently shared by the responsible
Virginia and Maryland officials in the years between 1956
and 1996, see ante, at 63, 76–77—the common law provides a
straightforward answer to that question. Although riparian
owners may withdraw water for domestic and agricultural
purposes, the Federal Government and, “[i]n the absence of
conflict with federal action or policy,” the States “may exer-
cise [their] police power[s] by controlling the initiation and
conduct of riparian and nonriparian uses of water.” Re-
statement (Second) of Torts § 856, Comment e (1979). More-
over, this case does not involve individual riparian landown-
ers’ withdrawals of water for their own domestic use, but the
Fairfax County Water Authority’s withdrawals for the use of
county residents. Under Virginia law, such “ ‘use of the wa-
ters of a stream to supply the inhabitants of [an area] with
water for domestic purposes is not a riparian right.’ ” Pur-
cellville v. Potts, 179 Va. 514, 521, 19 S. E. 2d 700, 703 (1942).
Clearly, then, the authority’s proposed use of Potomac wa-
ters cannot be defended as an exercise of absolute and unreg-
ulable riparian rights. It necessarily follows, I believe, that
such a use may only be made with the consent of the sover-
3 Va. Code Ann. Compacts App., pp. 342–343 (Lexis 2001).
4 Id., § 7.1–7, at 94 (emphasis added).

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82 VIRGINIA v. MARYLAND
Kennedy, J., dissenting
eign that owns the river. That sovereign is, indisputably,
the State of Maryland.
We need go no further. This case does not require us to
determine the precise extent or character of Maryland’s reg-
ulatory jurisdiction. Rather, the narrow issue before us is
whether Maryland may impose any limits on withdrawals
by Virginia landowners whose property happens to abut the
Potomac. Because those landowners’ riparian rights are—
like all riparian rights at common law—subject to the para-
mount regulatory authority of the sovereign that owns the
river, I would sustain Maryland’s exceptions to the Report
of the Special Master and enter judgment dismissing Virgin-
ia’s complaint.
Justice Kennedy, with whom Justice Stevens joins,
dissenting.
Failing to appreciate a basic rule of territorial adjudica-
tion, the Court concludes it must “reject Maryland’s histori-
cal premise” that in 1785 the State had title to the Potomac
River (River), its bed, and its waters. Ante, at 67. In my
respectful view, and contrary to the majority’s premise, the
circumstance that two parties both claim rights to a parcel
of land has no legal significance if one of the two parties has
clear title already, absent some further argument that the
claim against the holder of the title is reinforced by a history
of prescription, estoppel, or adverse use. Contra, ante, at
68 (relying on the fact that “the scope of Maryland’s sover-
eignty over the River was in dispute both before and after
the 1785 Compact” to conclude that Maryland lacked sover-
eignty over the River in 1785). Just as this basic rule of
property adjudication is true of disputes between two pri-
vate persons, it is true of title disputes between States. “No
court acts differently in deciding on boundary between
states, than on lines between separate tracts of land.”
Rhode Island v. Massachusetts, 12 Pet. 657, 733 (1838).
See also Rhode Island v. Massachusetts, 4 How. 591, 628

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Kennedy, J., dissenting
(1846) (“[A]scertain[ing] and determin[ing] the boundary in
dispute . . . , disconnected with the consequences which fol-
low, is a simple question, differing little, if any, in principle
from a disputed line between individuals”). Cf. Alabama v.
Georgia, 23 How. 505 (1860) (settling quiet title action be-
tween States by engaging in traditional quiet title analysis).
Since “[t]here is not in fact, or by any law can be, any
territory which does not belong to one or the other state; so
that the only question is, to which the territory belongs,” 12
Pet., at 732, a competent authority’s determination that a
sovereign’s title lies clear and unimpaired necessarily has
retrospective force. This is so despite the losing sovereign’s
prior attempt to gain what was not its own.
The majority, in the face of these doctrines and precedents,
nonetheless relies on the proposition that Maryland’s histori-
cal title is to be doubted because Virginia long disputed it
and the parties undertook to resolve the dispute. It is a
curious proposition to suggest that by submitting to adjudi-
cation, arbitration, or compact negotiations a party concedes
its rights are less than clear. The opposite inference is just
as permissible. The implication of the majority’s principle,
moreover, is that self-help and obdurate refusal to submit a
claim to resolution have some higher standing in the law
than submission of disputes to a competent authority.
Until today, the competent authorities to whom Maryland
and Virginia submitted their dispute have been clear and
unanimous on this point: As of 1784, the year before the
Compact, the Governor of Virginia could not enter the wa-
ters of the Potomac to cool himself by virtue of any title
Virginia then had to the riverbed. Title to the whole River,
and its bed, was in Maryland. First, in 1877, the parties
agreed, with later congressional approval, that Maryland had
clear title to the whole River dating from 1632. See Black-
Jenkins Opinion (1877), App. to Report of Special Master,
p. D–9 (hereinafter App. to Report of Special Master) (“The
intent of the [original 1632 Maryland] charter is manifest all

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84 VIRGINIA v. MARYLAND
Kennedy, J., dissenting
through to include the whole river within Lord Baltimore’s
grant”). Then, as if this 1877 determination were not
enough, this Court independently reviewed the question in
1899. The Court, too, reached the conclusion that Maryland
had clear title to the whole River dating from 1632. The
Court said, “the grant to Lord Baltimore, in unmistakable
terms, included the Potomac River.” Morris v. United
States, 174 U. S. 196, 223 (1899). And the Court confirmed
this determination in 1910. See Maryland v. West Virginia,
217 U. S. 1, 45–46. Thus, unless prescription had been
worked by some previous conduct to give Virginia at least
some limited rights, in 1784 Maryland had clear title to the
whole River, as much as in 1632.
Neither Virginia’s counsel nor the majority of the Court
today contends that prescription occurred prior to the Com-
pact of 1785. In 1784, therefore, under the law, Virginia had
little more than a land border between it and Maryland in
the area here under consideration; Virginia did not have a
river border since the River was not its own. That in 1784
Virginia did not admit Maryland’s clear title to this territory
and was unwilling to comply with Maryland’s continuing and
consistent demands that it respect Maryland’s sovereign con-
trol over the River did not cloud the smooth stretch of Mary-
land’s title back to 1632.
Whether the Governor of the Commonwealth, in 2003, may
cool himself in the River—or in this case, build a water pipe
for the benefit of communities not on the riverbank—without
so much as an “if you please” to the State of Maryland en-
tirely depends upon whether in the intervening time since
1784 Maryland has in some way ceded its sovereignty over
the River. See United States v. Cherokee Nation of Okla.,
480 U. S. 700, 707 (1987) (“[A] waiver of sovereign authority
will not be implied, but instead must be ‘surrendered in un-
mistakable terms’ ”); 12 Pet., at 732 (“[T]itle, jurisdiction, and
sovereignty, are inseparable incidents, and remain so till the
state makes some cession”).

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Kennedy, J., dissenting
Virginia asserts that an agreement and an award set out
in two documents establish that Maryland ceded Virginia an
unqualified right to enter upon Maryland’s territory. The
case, therefore, turns on these two documents: the 1785 Com-
pact between the two States and their 1877 arbitrated award
(Black-Jenkins Award or Award).
Via the 1785 Compact, Article Seventh, both States prom-
ised the other rights to use the River that presuppose nei-
ther could exclude the other from the River.
“The citizens of each state respectively shall have full
property in the shores of Potowmack river adjoining
their lands, with all emoluments and advantages there-
unto belonging, and the privilege of making and carry-
ing out wharves and other improvements, so as not to
obstruct or injure the navigation of the river.” Va.
Code Ann. Compacts App., pp. 342–343 (Lexis 2001).
Thus, in effect, they gave one another assurances of River
access in exchange for the identical, reciprocal pledge. The
mutual promise was sensible enough since at the time both
parties claimed to own the whole River, and equally, there-
fore, neither accepted the other’s claim to have any right to
gain access to the River. The Compact, in essence, was a
predictable and intelligent hedging agreement (protecting
both from the danger that at some later point the other’s
claim to full and clear title would be confirmed by a compe-
tent legal authority).
Once it was established by a competent legal authority
that Maryland had clear title to the whole River, the terms
of Article Seventh of the Compact, in retrospect, became the
sole fount of Virginia’s right to River access. The terms by
which the parties promised River access to one another be-
came relevant, as one would expect from a hedging agree-
ment, af ter occurrence of the development the parties
hedged against.

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86 VIRGINIA v. MARYLAND
Kennedy, J., dissenting
Maryland, as the territory’s sovereign, once could have ex-
cluded Virginia landowners from the River, but Article Sev-
enth abrogates Maryland’s right of sovereignty to this ex-
tent. By its clear language, Article Seventh creates a right
for citizen landowners to have some access to the River ter-
ritory by, for example, the construction of improvements
appurtenant to the shore.
Article Seventh, however, does not abrogate Maryland’s
sovereign right to exercise its police power, and the regu-
latory authority that implies, over its River territory; and
the majority does not contend otherwise. The citizen land-
owner rights created by Article Seventh, as a consequence,
remain subject to Maryland’s sovereign powers insofar as
that consists with Virginia’s guaranteed access. That the
landowners’ rights are so limited is well illustrated by the
very different language the parties used when they wanted
to abrogate one another’s police power over citizens or the
other State. For example, as the majority agrees, Articles
Fourth, Eighth, and Ninth of the Compact all contain ex-
press and particular police power abrogations. See ante,
at 66–67. So does Article Tenth. Article Seventh, how-
ever, stands in clear contrast to these provisions. It does
not contemplate the transfer or abrogation of Maryland’s po-
lice power. It cannot be the basis for concluding that Vir-
ginia’s citizens now have not just a right of access to the
River, but the additional right of access free of Maryland’s
regulatory police power. See Massachusetts v. New York,
271 U. S. 65, 89 (1926) (“[D]ominion over navigable waters,
and property in the soil under them, are so identified with
the exercise of the sovereign powers of government that a
presumption against their separation from sovereignty must
be indulged”).
As a result, Article Seventh sets up an awkward situation,
forcing this Court to reconcile a landowner right not to be
excluded with Maryland’s sovereign regulatory authority.
In effect, it forces the Court to inquire whether any particu-

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lar regulation amounts instead to an exclusion prohibited by
the Compact. That the Compact forces this determination,
parallel to that at issue in a case of an overburdened ease-
ment, is no reason to deny its plain language or the accepted
proposition that Maryland has long had title to the River
and its bed.
The next step is to consider the 1877 Black-Jenkins Award
and to ask whether that Award expands Virginia’s rights of
River access beyond what was provided in the Compact.
The Black-Jenkins Award affirms that Virginia, as much as
its citizens, has riparian rights under the 1785 Compact, to
the extent of the Commonwealth’s own riparian ownership.
See ante, at 69. The question remains, however, whether
Black-Jenkins converted Virginia’s right of riparian owner-
ship under Article Seventh to a right of sovereignty in the
waters. For, if it did not do so, then Virginia’s right of ac-
cess to the River is limited like that of any other riparian
owner under Article Seventh. In relevant part, the Award
states:
“Fourth. Virginia is entitled not only to full dominion
over the soil to low-water mark on the south shore of
the Potomac, but has a right to such use of the river
beyond the line of low-water mark as may be necessary
to the full enjoyment of her riparian ownership, without
impeding the navigation or otherwise interfering with
the proper use of it by Maryland, agreeably to the com-
pact of seventeen hundred and eighty-five.” Act of Mar.
3, 1879, ch. 196, 20 Stat. 482 (internal quotation marks
omitted).
The majority suggests this language gives Virginia sover-
eign rights to the River because it uses the words “Virginia”
and “full dominion.” See ante, at 72 (“The arbitrators did
not differentiate between Virginia’s dominion over the soil
and her right to construct improvements beyond low-water
mark”). That reading cannot be right for two reasons.

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88 VIRGINIA v. MARYLAND
Kennedy, J., dissenting
First, the evident design of Paragraph Fourth is to acknowl-
edge a Virginia access right parallel to that of its own citi-
zens who were riparian landowners. Paragraph Fourth sets
out two recitations, and they are in contradistinction. Vir-
ginia is granted “full dominion” up to the low-water line.
This is unlimited. What comes next is not. As to the
rights beyond this full dominion, that is to say beyond the
low-water line, Virginia has only the rights of a riparian
owner. If the arbitrators meant to set the two rights in par-
allel, as Virginia argues, they would not have used the word
“but” to distinguish them. Further, the phrase “a right to
such use” is limited by the phrase “riparian ownership.”
This is far different from saying Virginia has full dominion
“up to the low-water line, and with respect to” any improve-
ments it makes appurtenant to its shore.
Second, Black-Jenkins states that the limited rights Vir-
ginia has, the Commonwealth achieved by prescription.
Maryland acquiesced to Virginia’s adverse use, Black-Jenkins
says, as a result of Maryland’s adherence to Article Seventh
of the Compact.
“Virginia, from the earliest period of her history, used
the South bank of the Potomac as if the soil to low
water-mark had been her own. She did not give this
up by her Constitution of 1776, when she surrendered
other claims within the charter limits of Maryland; but
on the contrary, she expressly reserved ‘the property of
the Virginia shores or strands bordering either side of
said rivers, (Potomac and Pocomoke,) and all improve-
ments which have or will be made thereon.’ By the
compact of 1785, Maryland assented to this, and declared
that ‘the citizens of each State respectively shall have
full property on the shores of Potomac . . . and advan-
tages thereunto belonging, and the privilege of making
and carrying out wharves and other improvements.’
We are not authority for the construction of this com-
pact, because nothing which concerns it is submitted to

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Kennedy, J., dissenting
us . . . . Taking all together, we consider it established
that Virginia has a proprietory right on the south shore
to low water-mark, and, appurtenant thereto, has a priv-
ilege to erect any structures connected with the shore
which may be necessary to the full enjoyment of her
riparian ownership, and which shall not impede the free
navigation or other common use of the river as a public
highway.” App. to Report of Special Master D–18 to
D–19 (quoting Article Seventh of the Compact).
That Maryland’s “assent” and “declaration” in the Compact
prove Maryland’s acquiescence in Black-Jenkins’ prescription
analysis illustrates the limits of the Award: The prescriptive
rights it recognized stemmed from the Compact. Virginia’s
claims under Black-Jenkins rise as high as the Compact but
no higher. The Commonwealth can do no more than assert
those rights granted to landowners by Article Seventh.
The above analysis, of course, does not depend on the conclu-
sion that Maryland’s acquiescence was the sole basis for the
Black-Jenkins Award, as the majority contends. See ante,
at 75. A factor in any test can be a necessary, though not
sufficient, element. Here, the arbitrators’ express aim was
to apply “[u]sucaption, prescription, or the acquisition of title
founded on long possession, uninterrupted and undisputed,”
which they noted were intended to help sovereigns avoid the
“bloody wars” that territorial disputes occasion. See App.
to Report of Special Master D–17 to D–18. The inquiry into
acquiescence (i. e., whether the territory was disputed) fits
into that analytical framework as a necessary, though not
sole, factor. The other factors, such as Virginia’s long use,
were also necessary, though not sole, factors. This explains
why the arbitrators said Virginia’s long use and Maryland’s
acquiescence were “Tak[en] all together.” See id., at D–19.
It also explains why the text of the Award—which after all
is of greater significance than the arbitrator’s attached opin-
ion—distinguishes between Virginia’s full dominion up to the

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low-water line and its use rights beyond that point, a distinc-
tion consistent with Article Seventh.
The majority’s decision ultimately seems to rely on rights
stemming from some other, additional prescription to con-
clude that Paragraph Fourth expands Virginia’s rights. See
ante, at 74. It fails to explain, however, what other rights
Black-Jenkins identified other than those achieved by the
prescription discussed above. Notwithstanding the major-
ity’s conclusory position, the sole right acknowledged in
Black-Jenkins was that which was delimited by the operation
of Article Seventh
The majority also implies, in footnote 9 of its opinion, that
Virginia’s right to use the River free from Maryland’s regula-
tion is equally a matter of federal common law. See ante,
at 74–75, n. 9 (relying on Colorado v. New Mexico, 459 U. S.
176 (1982)). That suggestion cannot be right, however.
The doctrine on which the majority relies pertains to inter-
state bodies of water. As explained above, the Potomac
River belongs to Maryland and so is not an interstate body
of water. Those cases in which we have considered the
common-law rights of sovereigns who either both had title
to half of a river, or who both had full title to a river but at
different points in its flow, such as Colorado, are inapposite
to this unique, sole-title context.
Since Black-Jenkins does not expand Virginia’s right of ac-
cess, Article Seventh’s framework controls. The awkward-
ness of asking whether a regulation by Maryland amounts to
exclusion is heightened here, where Virginia, as a riparian
landowner, asserts its right to have access to the River for
the purpose of serving needs well beyond recognized ripar-
ian use. This, in turn, raises the question whether Maryland
can decide Virginia has too much population, and on that
ground deny Virginia access for the purpose of meeting
water demands.
This, to be sure, is a question of considerable difficulty, for
it is not our law or our constitutional system to allow one

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State to regulate transactions occurring in another or to
project its legislative power beyond its own borders. See
Baldwin v. G. A. F. Seelig, Inc., 294 U. S. 511, 523 (1935).
Virginia’s access rights, though not rights of sovereignty, are
rights held by a sovereign, which Maryland well knew when
it signed the Compact. And, nothing in the Compact gives
Maryland the power to regulate the Commonwealth of Vir-
ginia as most States can regulate their own riparian land-
owners; specifically, Paragraph Fourth of the Award (like
Article Seventh of the Compact) prohibits Maryland from
excluding Virginia from the River. These considerations
counsel careful deliberation before deciding whether Mary-
land regulation amounts to an exclusion in light of the partic-
ular riparian use at issue.
Determining whether a regulation is either (1) a legitimate
River regulation of riparian use, or (2) a wrongful exclusion,
under the Compact, of the riparian owner from the River,
may implicate some limitations based on a reasonable predic-
tion of consequences to the River’s flow. That is the ques-
tion that Virginia should have submitted to the Special Mas-
ter. The majority, however, simply holds that Virginia has
a right to gain access to and enjoy the River coextensive
with Maryland’s own. Its ruling denies the force of the his-
torical documents at issue. It has no logical basis either,
unless the majority also makes the silent assumption that
Virginia is constrained by some principle of reasonableness.
The majority’s interpretation, that Virginia’s right is whole,
sovereign, and unobstructed, otherwise leads to the conclu-
sion that Virginia could build all the way across the River if
the Commonwealth so chooses, as long as the Commonwealth
itself concludes the construction is an improvement appurte-
nant to its shoreline and not an obstruction to the River’s
navigability.
The anomaly that exists because of the rather unusual cir-
cumstance that Maryland owns the entirety of the River af-
fects this case’s difficulty; but it does not affect the fact that

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92 VIRGINIA v. MARYLAND
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the Court must confront the problem, not ignore it and send
Maryland and its rights away by fiat. This is particularly
true in light of the fact that Virginia’s right to access and
Maryland’s right to regulate have coexisted in actual applica-
tion for nearly 50 years. See ante, at 63. History shows
the framework can be workable.
If Maryland’s attempted regulation of Virginia contradicts
Virginia’s place in the federal system, that matter can be
explored from case to case. Here, however, the Common-
wealth did not ask the Special Master, as it should have, to
consider whether, given the nature of the riparian rights at
issue, see ante, at 81–82 (Stevens, J., dissenting), the effect
of the proposed use on the River, and the attempted regula-
tion at issue, Maryland has in effect excluded Virginia from
its rightful riparian use, as distinct from enacting reasonable
regulations of that use. Virginia is not due the broad relief
it instead now receives: the majority’s declaration that Vir-
ginia is the sovereign of whatever Maryland territory appur-
tenant to Virginia’s shoreline Virginia now chooses to claim.
In agreement with Justice Stevens, I would sustain Mary-
land’s objections to the Report of the Special Master and
enter judgment dismissing Virginia’s complaint. For these
reasons, with respect, I dissent.