Tidal Streams

These can be worked out either using Tidal Stream Atlases (book of arrows) Practice Navigation Tables page 8, or from Tidal Diamonds on the chart.

Find the time for the nearest tide for the primary port associated to the tidal diamonds or tidal flow pages in question (these will normally be Plymouth in the RYA Questions).

Find the High Water and the Low Water Heights and the Range of the tide (the HW minus the LW heights) Write down the HW time for the nearest HW (apply BST if necessary) Then fill in the times for 30mins either side of the times for HW as shown in blue. When you start it is easier to begin on a fresh sheet of paper and enter HW in the middle of the page.
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