Question 467Navigation General70% to pass
When utilizing a Pacific Coast chart, the reference plane of soundings is _______________.
AI Explanation
The correct answer is D) mean lower low water.
On Pacific Coast nautical charts, the reference plane for soundings (water depths) is the mean lower low water (MLLW) level. This is the average of the lower of the two daily low tides, as observed over a 19-year period. MLLW is the standard reference plane used for all charted soundings on the Pacific Coast of the United States.
The other options are incorrect because they represent different tidal datums that are not used as the reference plane for Pacific Coast chart soundings. Lowest normal low water, mean low water, and mean low water springs are not the standard reference used on these charts.
Related Questions
#465 All aids to navigation listed in the Mississippi River System Light List are shown as miles from a reference point and on the _______________.#466 The datum used for soundings on charts of the East Coast of the United States is _______________.#468 Mean lower low water is the reference plane used for _______________.#469 Mean high water is the reference datum used to measure _______________.#470 Mean high water is used _______________.