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All questions
Tides

Which sequence correctly turns compatible chart and tide inputs into a depth decision?

Short answer

Charted depth plus tide height, then compare with draught and safety margin

The governing relationship is compatible charted sounding plus predicted tidal height = estimated depth, followed by comparison with relevant draught and a separately chosen margin. The alternatives confuse unlike quantities or reverse the effect of rising water. Apply it to the limiting place and revise Depth, Height, and Margin.

Sources and scope

Reviewed by Richard Moore on . This answer is scoped to united kingdom and general recreational seamanship; check the current chart, publication, local rules and official operational guidance before acting afloat.

Quick check

Which sequence correctly turns compatible chart and tide inputs into a depth decision?