GIS-based analyses of time-series (1926-2009) digital elevation models (DEMs), developed from analogue navigation charts and digital hydrodata for both the flood and ebb-tide deltas at the Gippsland Lakes artificial entrance area (Victoria, Australia), allows the long-term bathymetric results of rubble training wall (or ‘groyne’) emplacement en echelon within the Reeves Channel to be evaluated. Reeves Channel form has progressively become more sinuous, and extensive flood and ebb-tide delta shoaling areas have also developed since groyne field installation. Deviation by successive coastal mangers from a proposed Reeves Channel groyne emplacement design (which can be found in a March 1927 Royal Commission report) may have contributed heavily to the time-series development of Reeves Channel sinuosity and flood and ebb-tide delta sediment accretion. Since inception of the AUD 32 million Lakes Entrance Sand Management Program (LESMP) in 2006, sediment management strategies aimed at reinstating a linear Reeves navigation channel have not been successful in the face of interference caused by the groyne field to ebb and flood-tide currents. Navigation channel monitoring using GIS shows that this interference causes dredged linear channel form to revert to a sinuous channel form soon after dredging operations cease. It is argued that future sediment management planning must include, as a component, morphological modelling of both flood and ebb-tide deltas to test the effects of groyne field engineering configuration change, and/or removal.