Chart Navigation & Plotting · Tidal Currents — Interpolation
From the Tidal Current Tables, what does the term 'slack water' denote?
- AThe instant of maximum flood velocity
- BThe moment of zero current velocity between flood and ebb✓ Correct
- CThe time of high water
- DThe average of flood and ebb velocities
Explanation
Slack water is the moment when the horizontal current velocity is zero as the flow reverses between flood and ebb. It does not necessarily coincide with high or low water (the time of slack vs. high water depends on the type of current).
Authority: NOAA Tidal Current Tables; Bowditch (Pub. No. 9)
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