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A marina was constructed in the Great Barrier Reef World Heritage Area in close proximity to coral reefs that could be damaged by excess turbidity generated during construction. Since there was uncertainty about both the fate of suspended sediments and their effect on corals, initial water quality constraints were set very conservatively. In order to better understand the movement of suspended sediment during construction, a numerical model study was commissioned using three-dimensional, numerical, hydrodynamic, and Lagrangian particle tracking models. The study was successful in: (1) increasing the understanding of and reducing the uncertainty of sediment dispersal patterns under a range of common forcing conditions; (2) testing the variation in suspended sediment concentrations over sensitive areas for two different outfall locations; (3) offering evidence that a good choice in outfall locations will reduce the threat to corals; and importantly (4) presenting the results in a way that enhanced understanding by nontechnical reef managers. This final result was achieved by creating movies of sediment movement that clearly demonstrated the complex hydrodynamic processes involved with near-coastal water currents. Specific model results showed: (1) that a more seaward outfall increases effluent dispersal away from sensitive areas; (2) the highest concentrations of effluent over sensitive sites occur during no wind and neap tide conditions; and (3) prevailing southeast winds advect effluent offshore, away from sensitive sites. CE Database subject headings: Reefs; Model studies; Sediment transport; Suspended sediments; Australia.

The field of storm surge modeling has developed and matured considerably over the past 30 years. Several operational surge models have been implemented in Europe over the past decade. These operational advances have been accompanied by research into new areas, chiefly coupled surge-wave models and data assimilation, both of which are covered in this review. Surge-wave models attempt to provide more realistic model physics for the crucial area of air-sea interaction. Assimilation techniques use available data to generate improved numerical solutions, despite model inadequacies. The current activity in surge modeling and related areas is highlighted by the large proportion of recent papers cited in this work. Despite this activity, there is a general recognition that inadequate meteorological inputs remain the weak link in surge modeling. In addition, the advances in midlatitude modeling are not mirrored in the tropics. This is largely due to difficulties in predicting the paths and properties of tropical storms, but it also serves to emphasize the importance that has been attached to storm surge modeling in Europe.