Chart Navigation & Plotting · Tides
Charted depth at a spot is 8 feet. The tide table predicts a height of tide of 3 feet at your ETA. A negative tide of −1 foot occurs later. What is the actual depth at ETA?
- A5 feet
- B8 feet
- C11 feet✓ Correct
- D7 feet
Explanation
Actual depth = charted sounding + height of tide = 8 + 3 = 11 feet at the ETA. (At the later −1 ft tide the depth would be 8 − 1 = 7 feet — a reminder to check the tide for the exact time you will be there.)
Authority: Tide Tables; Chart No. 1
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