The tidal flows in the Bay, as listed in the charts
, really apply only between the Channel buoys and not at low or low tide. The flow is mild compared to other bays (1-2 kts), but there are notable spots, particularly near Ballast Point where the flow is faster. There are a few areas, N of Ballast Point and near the carrier berths where there can be recognizable eddies, especially near the tide extremes.
As mentioned the main nuisance is drifting kelp. The Big Guy puts it there to keep us from being happy all year round.