The Port of Longview, Washington, and their tenant, EGT Development, LLC, partnered to develop a $230 million state-of-the-art grain export facility along the Columbia River; the first new grain export terminal developed in the Pacific Northwest in more than 25 years, setting new standards for efficiency in grain export shipping. As part of the lease agreement, the Port was responsible for design and construction of the in-water structures capable of accommodating Panamax-sized vessels and Columbia River barges while EGT was responsible for the upland development. The Port selected its engineering consultant to recommend layout alternatives and prepare construction documents for Berth 9, a combined barge unloading berth and a ship loading dock. With approximately 1,050 feet (320 meters) of usable Columbia River frontage and the need to simultaneously accommodate Panamax-sized vessels at a ship loading dock and Columbia River grain barges at a barge unloading berth, space for both berths was created by locating the ship berth further away from the shore and offsetting the barge berth to the landward side. This layout allowed for the construction of the facility without dredging while allowing for the possibility of construction of a second barge berth in the future. Minimization of in and over-water structures was established as a design objective to reduce the potential impacts to the environment. This was achieved by providing independent concrete platforms for the ship-loader towers and marine leg, connected by open-grated steel trestles that allows for light-passage through the grating. This paper describes the primary elements of the project, including development of a layout to accommodate ships and barges without dredging on a site with limited river frontage, selection of structural elements to minimize overwater coverage, and the construction process.
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