4.2 Signs of tidal flow

In tidal waters, it is important to understand what the tides is doing. With experience, it is possible to perceive tidal flow, perhaps by the ripples that a flow creates, or by the interaction of the tide with wind and swell. In an area of variable tide, the wind will tend to pick out areas where the tide is flowing against it with small waves, whereas regions of opposite flow can appear flat.

Photo taken in an estuary with the tide flowing out, the areas of flat water without ripples indicates where the flow is slow or forming eddies:

Tethered buoys provide one easy way to assess tidal stream.

Buoy in tidal stream. The small orange buoy, which is attached with a rope to the larger yellow buoy, floats behind it in the influence of the stream. The ‘cushion’ waves ahead of the buoy and the flattened area behind indicate flow from left to right.