[Reprinted from the American Journal of International Law, Volume 24, No. 3, July 1930]

DELIMITATION OF THE TERRITORIAL SEA

THE METHOD OF DELIMITATION PROPOSED BY THE DELEGATION OF THE UNITED STATES AT THE HAGUE CONFERENCE FOR THE CODIFICATION OF INTERNATIONAL LAW

(By S. Whittemore Boggs, Geographer, Department of State)

Since the legal rights of the coastal state and of foreign states within the territorial sea 1 differ greatly from the rights of all states on the high sea, it should be made possible for a navigator, or a fisherman, or the coastal state, to determine with certainty whether or not a vessel is in territorial waters or on the high sea. It will be practically impossible to negotiate a general convention embodying fundamental international law relating to territorial waters until the geographical problem of delimiting the zone of territorial waters is solved. The complexity and importance of the geographical problem are evident in the fact that, of the 28 "bases of discussion" which were formulated by the preparatory committee, for the consideration of the Commission on Territorial Waters at the Conference for the Codification of International Law recently held at The Hague, one-half related to the delimitation of territorial waters, while the other half related to legal rights and obligations.

The proposal of the delegation of the United States of America which was submitted at the Conference at the session of March 27, 1930, represented an attempt to view all of the problems of delimitation as a whole, and to set forth a body of rules both simple in application and definite in result. This is believed to be the first attempt to draft a comprehensive and systematic body of rules for the purpose, and it was suggested that they be studied objectively, so far as practicable, on the charts and maps of the coasts in which the participating countries were especially interested.

The American proposal was based on the assumption that, since we cannot choose our coasts but must take them as we find them, so the limit of the territorial sea, once the breadth of the belt is agreed upon, must be a line which is -derived directly from the coast line, in an automatic manner except where allowance must be made for existing agreements and situations.

In order to delimit the territorial sea it is necessary to have agreement regarding the breadth of territorial waters, the landward base line from which it is measured, and the method of drawing the seaward boundary line.

With reference to the question of the breadth of the territorial sea, and the base line, the American position is that territorial waters extend to three marine or nautical lines measured from low-water mark along the coast. Norway, Sweden, Finland, and Iceland claim four miles; several countries, principally in the Mediterranean, claim six miles. It was pointed out at the conference that four-fifths of the shipping of the world is conducted by nations which regard three nautical miles as the width of the territorial waters. In the interest of clarity and brevity the three-mile rule will be assumed.

1 At the Conference for the Codification of International Law, which was held at The Hague, March 13-April 12, 1930, the Second Commission (that on Territorial Waters) chose the term "territorial sea" in preference to the more commonly used term "territorial waters."

2 The nautical mile was defined by the Technical Subcommittee (appointed by the Commission on Territorial Waters) as the equivalent of one minutes of latitude at the particular latitude concerned-varying about 19 meters between the equator and the poles. The American delegation recommended the adoption of 1,852 meters as the invariable length of the nautical mile-the definition adopted by the International Hydrographic Conference at Monaco, in April 1929, and already accepted by at least half a dozen countries.

The Technical Subcommittee of the Commission on Territorial Waters defined the baseline as follows:

Subject to the provisions regarding bays and islands, the breadth of the territorial sea is measured from the line of low-water mark along the entire coast.

For the purposes of this Convention. the line of low-water mark is that indicated on the charts officially used by the Coastal State, provided the latter line does not appreciably depart from the line of mean low-water spring tides.

The problems involved in the method of delimiting territorial waters are almost entirely independent of the breadth of territorial waters-whether three miles, four miles, six miles, or any other width. In front of straight and simple convex coastlines there is general agreement as to the method of drawing the boundary line between the high sea and the territorial sea. Complications arise, however, when there are bays, islands, archipelagos, straits, and roadsteads to be taken into consideration. Difficulties increase when there are straits between islands, and islands within straits.

In the delimitation of territorial waters two groups of interests need to be taken into consideration: (1) navigation; and (2) fishing. The interests of navigation require a minimum of interference on the part of a coastal state, and the maximum of simplicity in the principles and rules for the delimitation of territorial waters. Interest in fishing rights is restricted to certain coasts and is of two sorts: (1) the interest of the coastal state in territorial waters as the zone in which its nationals have an exclusive right to fish; and (2) the interest of all countries whose fishermen visit the fishing banks to protect small fry and thus insure good fishing in the future.

Because it is an accepted rule of international law that only the nationals of the coastal state may fish in its territorial waters, there is a tendency, on the part of states whose coastal waters are good for fishing purposes, to delimit their own territorial waters in such a way as to acquire the largest possible area of territorial sea. In the present unsettled state of things a country sometimes attempts to apply the rules for delimiting territorial waters on its own coasts in a manner which it finds objectionable when applied by another country for the purpose of excluding foreign fishermen.

Any general convention relating to the territorial sea will necessarily take into account existing treaty and other arrangements, and existing situations in "historic waters." These arrangements and situations are believed to affect only the landward base-line from which territorial waters are delimited. There appear to be no agreements or understandings which affect the manner or method of drawing the boundary line between the high sea and the territorial sea.

If the territorial sea is to be delimited in a manner to occasion the least possible interference with navigation, it will be necessary to assume the viewpoint of one who is on the sea and who wishes to know where territorial waters begin. The viewpoint of a man on land who wishes to know where territorial waters end is of no more than theoretical importance except as it may be said to coincide with the fishermen's interest in those limited areas in which fishing is profitable. The difficulties hitherto encountered in delimiting portions of the territorial sea have arisen, however, largely from the fact that the problem has generally been considered from the viewpoint of a man on the land rather than the viewpoint of the navigator. This is particularly true with reference to bays, the discussion of which will be found in a later section.

THE GENERAL RULE FOR DELIMITATION

The literature on territorial waters frequently states that the three-mile belt is to be measured "following the sinuosities of the coast." But it is not clear how the sinuosities of the coast are to be followed.

Three different methods of drawing the line of the exterior limit of territorial waters have at different times been proposed:

(1) A line parallel to the general trend of the coast, following the sinuosities thereof;

(2) A series of straight leins, parallel to straight lines drawn from point to point along the coast and from island to island; and

(3) A line all points of which are precisely three miles (or any other distance) from the nearest point on the coast.

The first method (see Fig. 1-a),* that of a line following the sinuosities of the coast and drawn parallel to the general trend of the coast, is occasionally suggested in the literature. It is utterly impracticable, however, and was not proposed at the Hague Conference.

The second method is really a combination of two methods. The distinctive feature is that on concave coasts it follows a series of straight lines arbitrarily drawn. Several of the countries which signed the North Seas Fisheries Convention of 1882 interpret the ten-mile bay provision of that convention as entitling them to draw lines up to ten nautical miles in length in almost any in

These figures will be found on pages 530-533, infra.

dentation of the coast, however shallow it may be and however much it may exceed ten miles in breadth between the headlands. Thus there may be a series of ten-mile lines within a single wide bay with smoothly curved shores, drawn between points arbitrarily chosen. But along convex coasts straight lines are impracticable and here the second method coincides with that which is next explained. (See Figure 1-b, which is an actual case, copied from an unpublished foreign chart.)

But it does not seem altogether reasonable to use one method where the land penetrates into the sea, and another method where the sea penetrates into the land. Practically it presents considerable difficulties, because convexities and concavities of the coast are of all degrees and sizes, and grade off insensibly into one another. Since the straight lines must be drawn arbitrarily, it imposes upon the coastal state the burden of deciding where they shall be drawn, and the navigator cannot know where territorial waters begin unless the coastal state publishes the lines on charts.

The third method (see Fig. 1-c) is intended to meet the actual requirements of the navigator. It is a line every point of which is precisely three nautical miles from the nearest point on the coast.

This general principle, in the language of the American amendment presented at the Hague Conference, reads as follows:

"Except as otherwise provided in this Convention, the seaward limit of the territorial waters is the envelope of all arcs of circles having a radius of three nautical miles drawn from all points on the coast (at whatever line of sea level is adopted in the charts of the coastal State), or from the seaward limit of those interior waters which are contiguous with the territorial waters."

One and only one such line may be drawn in front of any coast

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The practicability of the third method is shown as follows. Finding his position at sea, and locating it on his chart, the navigator describes a circle of three-mile radius; if it cuts land or national waters he knows that he is in territorial waters; if it barely touches land (or national waters) he knows that he is exactly on the boundary line between the territorial sea and the high sea; if it does not touch at all he knows that he is on the high sea. (See Fig. 2 for illustration of all three positions.) Because only one such line can be drawn no

line needs to be drawn at all on the chart.

If the line is drawn, however, it will invariably be found to be the envelope of the arcs of circles of three-mile radius drawn from all points on the coastline and from the exterior limit of national waters. Although it takes due account of every point on even the most complex coast, it should be noted that the envelope of the arcs of circles constitutes a relatively simple line in all cases.R

The three methods coincide in results obtained in front of perfectly straight coast lines.

All three systems are geometrical in character. In fact any system for delimiting territorial waters must be derived geometriccally from the coast line. No nongeometrical line limiting territorial waters is conceivable, except a line which bears no relation whatever to the coast, and such a line would be inconceivable as a practical solution of the problem.

In order to present a complete picture of the problems involved in delimiting territorial waters it must be observed that although, by the principle of drawing the envelope of the arcs of circles, there is one and only one such line which can be drawn in front of any coast, it does not follow that there is only one coast line from which any line representing the limit of territorial waters can be drawn. In fact any boundary line between the territorial sea and the high sea which is derived by the "envelope" method may be derived from any one of a number of coast lines of almost infinite variety and character. Figure 3 is designed to illustrate this fact. If the critical points (A, B, C, etc., on the diagram) from which the "envelope" arcs are drawn should co

"National waters" are also called "inland waters" and "interior waters." These latter terms, although commonly employed, are somewhat inapt when applied to the waters of a bay or estuary which is contiguous with the territorial sea.

6 In Figure 1-c, note that although the arcs of circles of three-mile radius are drawn from all points on the coast, a small number of the arcs drawn from the outermost points on the coast extend out beyond all the others, and the outer portions of these constitute the "envelope." In the diagram these are the arcs which are swung from points A to L inclusive. The arcs described from all the intermediate points, for example from M, nowhere touch the "envelope."

FIG. 1. Suggested methods of delimiting the territorial sea: (a) Lines following the sinuosities of the coast, drawn parallel to the general trend of the coast. A vague and impracticable idea; (b) straight lines parallel to straight lines, drawn between selected points on a concave coast (with the arcs of circles elsewhere). This illustration is copies from an unpublished foreign chart; (c) the American proposal: A line every point of which is exactly three nautical miles from the nearest point on the coast, described as the envelope of the arcs of circles of three-mile radius drawn from all points on the coast.

3mi

FIG. 2. The navigator's method of ascertaining whether he is in territorial waters or on the high sea, if the limit is defined as the "envelope of the arcs of circles of three-mile radius." It is evident that the limit of the territorial sea need not be indicated on the chart.

FIG. 3. Two dissimilar coasts the limits of whose territorial waters are identical in form. The points from which the envelopes of the arcs of circles are developed (A, B, C, etc.) have exactly the same relative positions on the two coasts.

FIG. 4. Proposals for minimum "bays": (a) The American proposal; (b) the French proposal. The proposal may be said to have been, in each instance, that when the bay is larger than the minimum a straight line shall be drawn between headlands, or where the bay first narrows to ten miles in width, and that the three-mile limit will be measured out from the straight ine. With both proposals, where the bay has less indentation, the territorial sea limit will follow the "envelopes of the arcs of circles" drawn from all points on the coast inside the bay.