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the entrance bar and it eliminated the processes maintaining the shallow marginal
ocean shoals. The resulting symmetrical and deeper entrance bar and channel
reduced significantly the head loss for both the flood and ebb tide flows. The reduction in head loss across the entrance bar has improved the hydraulic efficiency of the
entrance and has enhanced tidal propagation into the estuary. This has increased the
Fig. 10.27 Schematic representation of the hydrodynamics at a typical symmetrical entrance
(Nielsen and Gordon 1980). The symmetrical jettied entrance configuration has improved hydraulic conveyance and reduces the sediment feed into the entrance channel. Wallis Lake Inlet 1974
(Photograph courtesy NSW Government)
A.F. Nielsen and A.D. Gordon