This case presents a single question: whether a Rhode Island statute1 which requires every foreign vessel and every American vessel under register for foreign trade that traverses Block Island Sound to take on a pilot licensed by the Rhode Island Pilotage Commission is within the scope of 46 U.S.C. § 211 (1970). The latter statute authorizes states to regulate the use of pilots "in the bays, inlets, rivers, harbors, and ports of the United States . . . ."2 Resolution of the question presented by this appeal turns on a factual determination as to whether Block Island Sound is a "bay" within the meaning of the federal statute.

Each of the plaintiffs is licensed by the state of Connecticut to pilot foreign flag and American registry vessels through Connecticut waters,3 and earns his living piloting ships into Connecticut ports. This activity necessitates traversing Block Island Sound. In April 1973, the Rhode Island State Pilotage Commission notified Gulf Oil Trading Corporation whose vessels were piloted by plaintiff Warner, that the employment of Warner violated Rhode Island's pilotage law.4 Plaintiffs Losch and Ball were likewise subject to being held in violation of the law, and all three were thus prevented from serving as pilots on ships involved in international trade.5 Plaintiffs challenged the validity of the pilotage law, and after disposition of several procedural issues,6 the district court rejected their claim, holding the Rhode Island law properly authorized by 46 U.S.C. § 211. We affirm.

The term "bay" appearing in § 211 is not defined by that statute. However, the term has been subject to judicial definition. It is clear that bays are among those "bodies of water which join the open sea" and are to be distinguished from "interior waters such as lakes and rivers." United States v. California, 381 U.S. 139, 162, 85 S. Ct. 1401, 1414, 14 L. Ed. 2d 296, 311 (1965). In that case the Supreme Court noted that the definition of such bodies of "inland water" must have an "international content since the outer limits of inland waters . . . determine the Country's international coastline . . . ," 381 U.S. at 162, 85 S.Ct. at 1414, 14 L. Ed. 2d at 311, and it accepted a recently ratified treaty, known as the Convention on the Territorial Sea and the Contiguous Zone,7 as affording the best definition. Id. at 165-67, 85 S.Ct. at 1415, 14 L. Ed. 2d at 312. Article 7 of this Convention which provides an extensive definition of "bays",8 permits a 24-mile maximum closing line for the mouths of bays and applies a "semi-circle test" for testing the sufficiency of the water area enclosed. The latter test requires that a bay must comprise at least as much water area within the closing line as would be contained in a semi-circle with a diameter equal to the length of the closing line. Section 3 of Article 7 provides an additional variation on the "semi-circle test": "Where, because of the presence of islands, an indentation has more than one mouth, the semi-circle shall be drawn on a line as long as the sum total of the lengths of the lines across the different mouths."

Plaintiffs contend and the defendants concede that under the semi-circle test Block Island Sound9 does not constitute a bay. The district court found, however, that the Convention's test ought more properly to be applied "to the entire geographical body of water enclosed within lines drawn at the East River in New York City on the west and between Point Judith, Block Island and Montauk on the east." Essentially the area enclosed would include Block Island Sound and Long Island Sound in combination; and this body of water, the court found, would constitute a bay within the meaning of the Convention.10

Plaintiffs contend that the district court erred in applying the semi-circle test to the combination of Long Island Sound and Block Island Sound. They claim that under the Convention a bay must be a "well-marked indentation" and "penetration." Plaintiffs assert that these criteria are not met because the Long Island Sound-Block Island Sound configuration is open at its western end where the East River separates Long Island from the "main land mass", and that when Long Island is removed from the picture there remains only "a mere curvature of the coastline" without the necessary "indentation" or "penetration". However, this claim must fail.

Under plaintiffs' analysis Long Island is to be considered "just another island off the coast" that cannot serve to define, as the district court found it did, the boundary edge of an inland bay. Yet, the Supreme Court has specifically noted that Long Island Sound "is considered inland water rather than open sea." United States v. Maine, 420 U.S. 515, 517 n. 1, 95 S. Ct. 1155, 1156, 43 L. Ed. 2d 363, 366 (1975). Further, as the district court noted, "plaintiffs' own expert could give no reason why" the semi-circle test should not be applied to the combination of Long Island Sound and Block Island Sound. The court found this to be the most "sensible" configuration upon which to apply the semi-circle test and we cannot say this judgment was improper, particularly since the Convention provides that "(w)here . . . an indentation has more than one mouth, the semi-circle shall be drawn on a line as long as the sum total of the lengths of the lines across the different mouths." See Art. 7, § 3, supra n. 8. Accordingly, as the district court properly found, Block Island Sound is contained within and is a "bay" within the meaning of 46 U.S.C. § 211.

The court also found Block Island Sound to be a bay on an alternative theory, viz. that it was an "historic" bay and therefore need not meet the Convention's definitional requirements. See Art. 7, § 6, supra n. 8. " Historic" bays are those "over which a coastal nation has traditionally asserted and maintained dominion with the acquiescence of foreign nations." United States v. California, supra 381 U.S. at 172, 85 S. Ct. at 1419, 14 L.Ed.2d at 317. In holding Block Island Sound an "historic" bay, the district court noted that foreign fishing vessels are not permitted to fish in the sound. The court also credited the testimony of defendants' expert witnesses and the documentary evidence of early maps which indicated that the area directly to the east of Block Island was used as an anchorage and harbor as far back as the 1770's.11 The court also noted that there are numerous shallow soundings throughout the sound as well as navigational hazards which " belie the assertion that the sound (can) be considered part of the open ocean."

Despite this evidence, however, we here decline to rule whether Block Island Sound is an "historic" bay within the meaning of the Convention and United States v. California, supra. In California, which involved a dispute between the federal government and the state of California over ownership of offshore seabeds, the United States disclaimed that any of the disputed areas were "historic" inland waters. The Supreme Court avoided holding that such a disclaimer would always be decisive, "for a case might arise in which the historic evidence was clear beyond doubt." 381 U.S. at 175, 85 S.Ct. at 1421, 14 L. Ed. 2d at 318. However, the Court held the disclaimer decisive under the circumstances of that case because of what it characterized as "questionable evidence of continuous and exclusive assertions of dominion over the disputed waters . . . ." Id. While the United States government is not involved in the present case, and has not issued any disclaimer as to Rhode Island's historic rights in Block Island Sound, nevertheless we consider it significant that although considerable historical evidence was presented at trial, "specific acts of dominion were not introduced . . . ," a lack also noted by the district court. Such a record does not appear to us sufficient in light of United States v. California, supra, to support a claim that Block Island Sound is an "historic" bay. Moreover, it is unclear just what would be the limits to Block Island Sound under the historic bay theory. This uncertainty is particularly troublesome in view of the fact that the "outer limits of inland waters . . . determine the Country's international coastline." United States v. California, supra at 162, 85 S. Ct. at 1414, 14 L.Ed.2d at 311. We therefore refrain from ruling on this question.

Plaintiffs also contend that as a matter of constitutional law their Connecticut pilot licenses are valid to traverse the waters of Block Island Sound en route to a Connecticut port.12 Plaintiffs maintain that as long as a vessel does not enter or depart from a Rhode Island port, that state cannot regulate pilotage of the vessel through its waters. Plaintiffs seek support for this claim in 46 U.S.C. § 215 which exempts coast-wise steam vessels from state regulation. They point to the saving clause of that statute which provides:

". . . Nothing in (this) title . . . shall be construed to annul or effect any regulation established by the laws of any State, requiring vessels entering or leaving a port in any such State . . . to take a pilot duly licensed or authorized by the laws of such State . . .." (Emphasis supplied).

They assert that this language limits a state's authority to regulate pilotage solely to ships entering and departing its ports. However, this claim cannot avail. Plaintiffs' interpretation is highly implausible in light of 46 U.S.C. § 211, the statute directly at issue in this case, which not only authorizes state pilotage regulations for vessels heading to the "port" of a particular state, but also validates laws concerning "pilots in the bays, inlets, rivers, harbors, and ports of the United States . . .." (Emphasis supplied). Moreover, plaintiffs are unable to cite any authority in support of their proposition. Leech v. Louisiana, 214 U.S. 175, 29 S. Ct. 552, 53 L. Ed. 956 (1909), to which they point, is inapposite. Leech dealt with pilotage in waters forming the boundaries between two states and with 46 U.S.C. § 212 which permits a vessel to use a pilot licensed in either state regardless of which state's port the vessel travels to.13 See The Glenearne, 7 F. 604, 607 (D.Or.1881). Block Island Sound, however, does not serve as a boundary between states. Plaintiffs' reliance on The Swift Arrow, 292 F. 651 (D.Mass.1923) is likewise misplaced. In that case a Massachusetts licensed pilot won a judgment for pilotage fees because the vessel refusing his services mistakenly used a Rhode Island pilot to navigate into a Massachusetts port. The case dealt only with the narrow issue "of the obligation to take a Massachusetts pilot for (a) Massachusetts port" where the vessel in question was on waters that did not form a boundary between states. Id. at 653. It does not stand for the proposition asserted by plaintiffs, viz. that a Massachusetts pilot license was valid for traversing Rhode Island waters because the ship was headed toward a Massachusetts port. Indeed, if we were to accept plaintiffs' interpretation, a vessel heading to one state's port could be navigated by a pilot licensed solely in that state even if the vessel were to travel through coastal waters of numerous other states with which the pilot was completely unfamiliar. Such a holding would deprive states of the right, granted them by 46 U.S.C. § 211, to promote navigational safety and to protect the environmental integrity of their coastlines (from, e. g., oilspills caused by tankers running aground) by regulating pilotage of vessels through their waters.

Plaintiffs also claim that Rhode Island may not regulate their " piloting activities" because the routes they utilize in piloting vessels through Block Island Sound are more than three miles off the Rhode Island shore. Plaintiffs contend that Rhode Island only has territorial jurisdiction three miles from its seashore by virtue of the Submerged Lands Act of 1953,67 Stat. 29, 43 U.S.C. § 1301 et seq. (1970). We do not, however, find merit in this claim. The issue of a state's territorial limits, see, e. g., United States v. California, supra and United States v. Maine, supra, is distinct from that of its right to control navigation. States have been permitted to assert their pilotage regulations at distances considerably greater than three miles from their shores. See, e. g., Wilson v. McNamee,102 U.S. (12 Otto) 572, 573-74, 26 L. Ed. 234, 235 (1881) ("about fifty miles from . . . port"); The Whistler, 13 F. 295, 296 (D.Or.1882) ("about 30 miles from the (river) mouth"). By permitting states to regulate local pilotage Congress sought to protect vessels from "invisible hazards" that may be present in a state's waters until the ship can be guided to the open sea.14 See Kotch v. Bd. of River Port Pilot Comm'rs, 330 U.S. 552, 558, 67 S. Ct. 910, 913, 91 L. Ed. 1093, 1097, rehearing denied, 331 U.S. 864, 67 S. Ct. 1196, 91 L. Ed. 1869 (1947). And there is no statutory or other basis for imposing a three-mile limit on such regulation.

Affirmed.

46-9.1-1. Legislative declaration. The findings and declaration made by § 46-9-1 are hereby made applicable to this chapter.

46-9.1-2. Definitions. For the purposes of this chapter, and as used herein the following terms shall have the following meanings:

(2) "Block Island Sound" the waters of the state west of a line drawn from the easterly point of Point Judith to the southeasterly point of Block Island and north of a line drawn from the said southeasterly point of Block Island to the easterly point of Montauk Point, Long Island, New York.

(4) "Block Island Sound Pilot License" a license issued to a person to pilot vessels in Block Island Sound by the state pilotage commission under the provisions of this chapter.

(6) "Register" every foreign vessel and every American vessel engaged in foreign trade coming into and going out of . . . Block Island Sound waters shall be regulated by the provisions of this chapter and the rules and regulations promulgated thereunder by said commission.

46-9.1-3. Pilotage commission. The Rhode Island state pilotage commission . . . shall have control and jurisdiction over pilotage of vessels entering or departing from any port or landing place of the state or transversing the waters of Block Island Sound.

46-9.1-5. Vessels required to take pilot. Every foreign vessel and every American vessel under register entering or departing from any port or landing place of the state or transversing the waters of Block Island Sound shall take a pilot licensed under this chapter . . .; and such vessels shall be subject to rules and regulations promulgated by the commission. In case of refusal to take such pilot, the master, owner, agent or consignee of any such vessel shall pay the established pilotage fee as if a pilot had been employed.

46-9.1-10. Use of unlicensed pilots. (a) It shall be unlawful for the master, owner, agent or consignee of any vessel, not exempt from the provisions of this chapter, entering or departing from any port or landing place of the state or transversing the waters of Block Island Sound to take on any person not licensed as a Block Island Sound pilot . . . to pilot such a vessel in said waters.

(c) Violations. Violation of the provisions . . . of this section shall be a misdemeanor punishable by a fine not to exceed five hundred dollars ($500); or by imprisonment not to exceed one (1) year, or both.