33 CFR §162.240

1. (a)Definitions. The term “Tongass Narrows” includes the body of water lying between Revillagigedo Channel and Guard Island in Clarence Strait.
2. (b)No vessel, except for public law enforcement and emergency response vessels, floatplanes during landings and take-offs, and vessels of 23 feet registered length or less, shall exceed a speed of 7 knots in the region of Tongass Narrows bounded to the north by Tongass Narrows Buoy 9 and to the south by Tongass Narrows East Channel Regulatory marker at position 55°19′22.0″ N, 131°36′40.5″ W and Tongass Narrows West Channel Regulatory marker at position 55°19′28.5″ N, 131°39′09.7″ W, respectively.
3. (c)No vessel shall while moored or at anchor, or by slow passage or otherwise while underway, unreasonably obstruct the free passage and progress of other vessels.
4. (d)No vessel shall moor or anchor to any structure of the United States other than mooring piers, wharves, and floats without the consent of the Commander, Sector Southeast Alaska.