There is a significant reduction in the tidal range between Bass Strait and the body of the bay. The majority of this change takes place at The Entrance. Previous work on tidal currents throughout the bay was carried out as part of the Port of Melbourne Corporation Channel Deepening Project investigations (Cardno Lawson Treloar, 2007a).

The tidal currents show a marked variation in the bay with current speeds exceeding 3.5 m/s in Port Phillip Bay Heads, over 1 m/s in the South of the Bay channels, and generally below 0.2 m/s in the body of the bay north of the Sands. As a result, tidal currents are important to coastal processes and sediment movement in The Entrance and the Sands, but are less significant in other areas.

For the portion of the bay which is north of the Sands and adjacent to the study area, the tidal currents are weak with speeds of less than 0.2 m/s, with a slight increase in speed closer to the Sands. At CSIRO’s Great Sands location, Walker (1997) reports tidal current speeds just above 0.1 m/s. Close to the Sands, the tidal currents increase near the northern ends of the channels and there are eddies created, particularly on the flood tide near the ends of Symonds Channel and to the north-east of Hovell Pile (Prytz & Heron, 1994).

Cardno (2011c) found that during storms, current magnitudes of approximately 0.3 - 0.6 m/s could occur at Point Richards, Point George and south of St. Leonards Pier.

Little previous work has been undertaken for the open coast in terms of hydrodynamics and no current measurements are available away from the Port Phillip Bay area and the Heads.