State jurisdiction over water

• Author: John H. Currie, Craig Forcese, Joanna Harrington, Valerie Oosterveld
• Pages: 381-460

381

CHAPTER 5

STATE JURISDICTION OVER WATER

Over 70 percent of the Earth’s surface is covered with water. Human beings obviously do

not inhabit this “territory” in the same way as they do land. Yet, the oceans, rivers, and

lakes of the world are an important source of resources, both biotic and mineral. They

also provide fundamentally important means of transportation that are vital to travel,

trade, and security. States therefore have an intense interest in the jurisdictional regimes

applicable to the water regions of the world.

In our discussion of state jurisdiction over water, we f‌irst examine “inland” waterways

and then turn to oceans.

A. INLA ND WATERWAYS

Inland waterways are those bodies of water or watercourses, such as lakes and rivers, that

are enclosed by land. It is dif f‌icult to extract generic rules of international law from the

many legal regimes that govern the world’s inland waterways. Most signif‌icant rivers and

lakes that are bounded by more than one state are regulated by treaty, the specif‌ic terms

of which vary. Consider, for example, comments made by the International Court of Jus-

tice in a recent case concerning rights of navigation along one particular inland waterway:

Dispute Regarding Navigational and Relat ed Rights (Costa Rica v Nicaragua), Judg-

ment, [2009] ICJ Rep 213

32. According to Costa Rica, its right of free navigat ion on the part of the San Juan r iver

that is in dispute derives on the one hand from certain treaty provisions in force between

the Par ties, primarily but not exclusively the Treaty of Limits of 15 April 1858, and on

the other hand from the rules of general international law that are applicable, even in the

absence of treaty provisions, to navigation on “international rivers”. The San Juan is said

to fall i nto this category, at least as regards the section whose course follows the border,

with Costa R ica thus possessing a customar y right of free navigation in it s capacity as a

riparian State.

33. According to Nicaragua, on the contrary, the San Juan is not an “international river”,

since it f‌lows entirely within the territor y of a single country by virtue of the provisions

of the 1858 Treaty of Limits, which establish t he border in such a way that no part of the

river fal ls under the sovereignty of a State other than Nicaragua . Moreover, Nicaragua

challenges t he existence of a general régi me that might be applicable, under c ustomary

international l aw, to rivers whose course, or one of whose banks, constitutes the border

between two States, and more widely to “international rivers”. Lastly, according to Nic-

382 INTERNATIONAL LAW: DOCTRINE, PRACTICE, AND THEORY

aragua, even if such a régime were to exist, it would be superseded in this case by the

treaty provisions which def‌ine the status of the San Juan river and govern the r iparian

States’ right of navigation. It is these special provisions whic h should be applied in order

to settle the present dispute, in any event that part of it relating to t he right of navigat ion

on the river.

34. The Court does not consider that it is required to take a position in this case on wheth-

er and to what ex tent there exi sts, in customa ry international law, a régime applicable

to navigation on “international rivers”, either of universal scope or of a regional nature

covering t he geographical area in which the San Juan is situated. Nor does it consider,

as a result, that it is required to sett le the question of whether the San Juan falls into the

category of “international rivers”, as Costa Rica maintains, or is a national r iver which

includes an international e lement, that being the argument of Nicaragua.

35. Indeed, even if categorization as an “international river ” would b e legally relevant

in respect of navigation, in that it would entail the application of r ules of customary

international law to that question, such rules could only be operative, at the very most, in

the absence of any treaty provisions that had the effect of exclud ing them, in par ticular

because those provisions were intended to def‌ine completely the régime applicable to

navigation, by the ripar ian States on a specif‌ic river or a section of it.

36. T hat is precisely t he case in t his instance. T he 1858 Treaty of Lim its completely de-

f‌ines the rules applicable to the sect ion of the San Juan river t hat is in dispute in respect

of n avigation. Interpreted in the light of t he other treaty provisions in force between

the Parties, and in accordance with the arbitr al or judicial decisions rendered on it, that

Treaty is su ff‌icient to settle the question of the extent of Costa Rica’s right of free navi-

gation which is now before the Court. Consequent ly, the C ourt has no need to consider

whether, if t hese provisions did not exist, Costa R ica could nevertheless have relied for

this purpose on r ules derived from international, universal or regiona l custom. . . .

Given the situation-specif‌ic nature of most inland waterway legal regimes, we can only

make a few general observations about the international law governing these regimes,

and then turn to one specif‌ic example: the Canada-US inland waterways regime.

1) General Observations

In simple terms, inland waterways can be divided into three categories: those that are

entirely within the territory of a single state; those that f‌low from one state to another ;

and those that lie or f‌low along a border between states. Inland waterways completely

enclosed by a single state present relatively few diff‌iculties in international law: “Where

a river lies wholly within the territory of one state, it belongs entirely to that state, and

generally speaking no other state is entitled to rights of navigation on it.”1 In other words,

such inland waterways are part of a state’s sovereign territory in much the same way as its

land territory. The state enjoys plenary jurisdiction over these waterways.

1 Ivan A Shearer, Starke’s International Law, 11th ed (Toronto: Butterworths , 1994) at 175.

Chapter 5: St ate Jurisdiction over Wat er 383

Rivers and lakes that straddle or demarcate international borders c ause greater com-

plications. Consider this discussion of navigation rights:

Also where a river passes through several states, each state owns that part of the river

which run s through its terr itory, but controversy has centred round the question of the

rights of riparian and other st ates to navigate along the whole length of the river. Several

writers on inter national law . . . have been of the opinion that there is a general right of

passage for all states along such international rivers, but this view has never been gen-

erally accepted in pract ice, and is cert ainly not recogn ized as a customary pr inciple of

international law. . . . [S]uch measures of freedom of navigation as become established on

internat ional waterways [a re] almost entirely t he creation of treat y.2

Water in international inland waterways is also a key resource, use of which may cause

frictions between states. Consider these observations:

It is believed th at there is a general readiness of states to admit that any . . . use or diver-

sion [of,] or inter ference [with, water f‌low] by one riparian state injuring the free navig-

ability of a navigable internationa l waterway to t he detriment of a co-riparian st ate is a

breach of inter national law. Short of t his, it is perhaps on ly possible to say that there is

a duty on a riparia n state not, by any use of the river waters under its control to cause

grievous or irreparable damage of an economic character on other ripar ian states, for

example p ollution, which m ight reasonably have been prevented. . . . Where the rivers

concerned form part of a drainage basin, each riparian st ate is entitled to a reasonable

and equitable share in the benef‌icial uses of the waters of the basi n, a principle applied

in numerous treaties.3

The International Law Commission has attempted to give effect to some of these gen-

eral principles, with its efforts ref‌lec ted in the following treaty:

Convention on the Law of the Non-navigational Uses of International Watercourses,

21 May 1997, UN Doc A/51/869 (not yet in force)

PART II.

GENERAL PRINCIPLES

Article 5

Equitable and reasonable utilization and par ticipation

1. Watercourse States shall in their respect ive territories utilize an international water-

course in an equitable and reasonable manner. In partic ular, an international watercourse

shall be u sed and developed by watercourse States with a view to att aining optimal and

sustainable uti lization thereof and benef‌its therefrom, taking into account the interests

of t he watercourse States concerned, consistent with adequ ate protection of the water-

course.

2 Ibid.

3 Ibid at 177.