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Source: https://erdc-library.erdc.dren.mil/jspui/ ; One of the techniques used by the US Army Corps of Engineers to alleviate the high costs of maintenance dredging necessary to provide adequate dimensions in the entrance channels to the ports and harbors of the United States is known as advance maintenance dredging. Advance maintenance is defined as the channel dredging dimensions beyond the dimensions economically feasible required to maintain the dimensions during the budget year or until the next dredging cycle, This report evaluated the effectiveness of advance maintenance in producing desired results by examining its effects on the shoaling characteristics of 10 entrance channels. Three of the channels are located on the southeast Atlantic coast of the United States, three on the Gulf coast, and four on the northwest Pacific coast. At some of the sites, the effect of channel enlargement was included, since the initial performance of advance maintenance along a particular channel segment is technically "new work" dredging. Evaluations presented were based on an empirical technique of analysis using data from hydrographic survey maps and historical dredging records obtained from Corps District Offices. A brief description of its physical and hydraulic characteristics is included with the evaluation of each project. Results obtained in this study varied among the projects. In general, overdepth advance maintenance was most beneficial at projects where the infill rate was not sensitive to dredged depth while overwidth advance maintenance appeared to be most effectfve in channels where the location of the problem shoal was consistent from season to season. It is recommended that an analysis of the shoaling characteristics of a navigation project be conducted prior to the implementation of advance maintenance dredging at that project.