USCG Exam PracticeTides and currents — predictions and corrections
The vertical clearance under a fixed bridge will be LEAST at which tidal condition?
- A. At mean sea level
- ✓ At high waterCorrect
- C. At mean lower low water
- D. At slack water following ebb
Why B is correct
Bowditch Ch. 9 §904 states that heights of features such as bridges are referenced to Mean High Water, so vertical clearance shrinks as the tide rises. Clearance is therefore least at high water.
Cited:Bowditch Ch. 9 §904