The inundation of low-lying terrestrial areas fringing coastal lagoon or tidal inlet environments is an ever-present threat, and such vulnerability increases with on-going demographic and catchment change. Coastal zone managers require access to high resolution inundation extent mapping data, to allow for effective urban and environmental planning. In this paper, the results of a flood extent mapping and visualisation case-study from Loch Sport, Victoria, Australia, are reported. This township is located upon subdued terrain along the shores of an extensive coastal lagoon system known as the Gippsland Lakes. A high-resolution digital elevation model (DEM) of the Loch Sport township area has been derived via application of LiDAR data. From this model, flood inundation extents at 0.1m intervals have been derived, which have been validated using aerial vertical and oblique imagery captured during a catchment flood event which occurred in June 2007. Two interactive web-based inundation visualisation tools have also been developed during this research. These tools have been applied as a flood extent information dissemination medium to assist in coastal zone stakeholder inundation scenario decision-support, awareness and consensus-building activities. Potential applications of inundation extents include future flood extent estimation/prediction with individual land parcel resolution for flood event contingency and emergency management tasks, and immediate application in local management agency land development planning schemes. The exemplification presented here indicates the emergence of new incentives for spatial database building and integration in public-service agencies that are tasked with supporting integrated coastal zone management (ICZM) initiatives.