Hydrography including soundings, rocks, and shoals in this area was transferred from smaller scale chart 16220. Hydrography from 16220 was taken from numerous ship tracks or older charts, including Russian charts. Sufficient data is not available to correct depths to a common datum. Investigations reveal that 3.7 to 5.5 meters / 12 to 18 feet should be added to many depths to adjust them to Mean Lower Low Water.
