72 COLREGS apply and are enforced by USCG.
Pilotage is compulsory for all foreign vessels and U.S. vessels engaged in foreign trade. Pilotage is optional for U.S. vessels engaged in the coastwise trade with a federally licensed pilot on board.
Local magnetic disturbance. - Differences of as much as 3° from normal variation have been observed along Henderson Inlet.
The channel through Balch Passage is only about 100 yards wide between the 10-fathom curves, and the scale of the chart is small. Vessels should stay carefully in midchannel, traffic permitting.
Squaxin Passage - The passage is narrow, and strangers should proceed with caution. The S shore should be favored, and, at the W end, the N point of Steamboat Island should be favored. The principal danger in the passage is a reef which bares at extreme low water, SE of Hope Island; a buoy is near its S end. This reef is easily avoided by keeping the N point of Steamboat Island well open of the S point of Hope Island.