Chart Navigation & Plotting · Tides
Vertical clearance under a bridge is charted relative to which datum on U.S. charts?
- AMean Lower Low Water
- BMean High Water✓ Correct
- CMean Sea Level
- DChart sounding datum
Explanation
Overhead (vertical) clearances such as bridges and power cables are referenced to Mean High Water on U.S. charts, the conservative high-water reference, while depths are referenced to MLLW.
Authority: U.S. Chart No. 1; NOAA charting standards
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