Selection of Dredging Projects for Maximizing Waterway System Performance

Abstract

Budget allocation to annual maintenance dredging projects conducted by the U.S. Army Corps of Engineers is addressed. Of the many projects requested, only a subset may be selected for funding because of budgetary constraints. The benefits of conducting maintenance dredging at one dredging project depend on other projects in the system that also are being dredged to take advantage of transportation efficiency gains derived from deeper navigable waterways. The proposed integer programming models and heuristic solution algorithms selected dredging projects for funding, while taking into account interdependent benefits. The models considered the waterway network topology, which was derived from flow data of historic waterborne cargo. The solution algorithms ensured efficient computational performance and quality of solutions. The models and algorithms were tested on example port systems from the Great Lakes region, as well as from mainline coastal ports and inland waterways. The models were shown to increase the amounts of system cargo throughput directly supported by dredging relative to traditional rank-order approaches that did not consider project interdependencies. This result was true especially for scenarios in which the overall budget was small relative to the total of all funding requests in question.