Except as provided in paragraph (b) of this section, the Thunder Bay National Marine Sanctuary and Underwater Preserve (Sanctuary) consists of an area of approximately 4,300 square miles of waters of Lake Huron and the submerged lands thereunder, over, around, and under the underwater cultural resources in Thunder Bay. The eastern boundary of the sanctuary begins at the intersection of the southern Alcona County boundary and the U.S./Canada international boundary (Point 1). The eastern boundary of the sanctuary approximates the international boundary passing through Points 2-5. The boundary continues west through Point 6 and then back to the northeast until it intersects with the 45.83333°N line of latitude at Point 7. The northern boundary follows the line of latitude 45.83333°N westward until it intersects the −84.33333°W line of longitude at Point 8. The western boundary extends south along the −84.33333°W line of longitude towards Point 9 until it intersects the ordinary high water mark at Cordwood Point. From there, the western boundary follows the ordinary high water mark as defined by Part 325, Great Lakes Submerged Lands, of P.A. 451 (1994), as amended, cutting across the mouths of rivers and streams until it intersects the line formed between Point 10 and Point 11 south of Rogers City, MI. From there the boundary moves offshore through Points 11-15 in order until it intersects the ordinary high water mark along the line formed between Point 15 and Point 16. At this intersection the boundary continues to follow the ordinary high water mark south until it intersects with the line formed between Point 17 and Point 18 near Stoneport Harbor Light in Presque Isle, MI.

From there the boundary moves offshore through Points 18-20 in order until it intersects the ordinary high water mark along the line formed between Point 20 and Point 21. At this intersection the boundary continues to follow the ordinary high water mark south until it intersects the line formed between Point 22 and Point 23 near the Lafarge dock in Alpena, MI. At this intersection the boundary moves towards Point 23 until it intersects the ordinary high water mark. At this intersection the boundary follows the ordinary high water mark south until it intersects the southern Alcona County boundary along the lined formed between Point 24 and Point 25 in Greenbush, MI. Finally, at this intersection the boundary moves eastward and offshore until it reaches Point 25.

Excluded from the Sanctuary boundary are the following ports:

Rogers City;

Presque Isle; and

Alpena.

The coordinates of each boundary area appear in appendix A of this subpart.