Modelling Ocean Disposal of Dredged Sediments Using ADDAMS

The ADDAMS suite of computer program modules, which addresses the assessment of the ocean and land disposal of dredged sediments, is under continuing development by and available free of charge from the U.S. Army Engineer Waterways Experiment Station, Vicksburg. The potential of the ADDAMS modules STFATE, LTFATE, and MDFATE for application to the preliminary assessment of the ocean disposal of dredged sediments from marinas and small boat harbours under Australian conditions is being investigated. The module MDFATE, which models both the short- and long-term fate of multiple dumps of sediments, has been assessed using data from ocean disposal sites at Weipa, Townsville, and Hay Point. Since MDFATE incorporates most of STFATE and LTFATE, which respectively model the short-term fate of a single dump and the longterm fate of sediments on the seabed, this also constitutes an assessment of the latter two modules. Within the limitations of the available data, the performance of MDFATE was reasonably robust and generally satisfactory for the preliminary assessment of ocean disposal sites.