Hawaii & Alaska
Sand, sediment and debris are removed from the seafloor by the Westport, a hopper dredge operated by Manson Construction, near the Port of Alaska on April 8, 2019. After dredging material is collected from the area near the docks, it is deposited 3,000 feet offshore, where the currents cannot bring it back to the harbor. Courtesy Photo via DVIDS

AK - Corps continues legacy of dredging at Port of Alaska

All summer long, a crimson and white boat moves back and forth through the waters near the Port of Alaska collecting silt, sand and gravel off the seafloor to allow vessels to navigate the harbor in Anchorage.

The boat is a dredging vessel called the Westport, operated by Manson Construction of Seattle, Wash., which the U.S. Army Corps of Engineers – Alaska District contracted to maintain the mooring areas for the past three years.

An estimated 2,400 to 2,600 cargo containers arrive at the port each week to keep stores supplied with consumer goods throughout the Interior and Southcentral Alaska, said Julie Anderson, operations branch chief for the Alaska District.

“We all want our stuff, so it is important that we provide an environment in which shippers can be on time,” Anderson said.

However, underwater shoals in Cook Inlet cause sediment to settle in the harbor creating depths that ships cannot traverse. Shoaling north, south and at the dock face contributes to most of the accumulation in combination with some of the largest tidal fluctuations in the world. A small amount of material comes from sedimentation, the process of sand and silt washing downstream. Together, these processes gradually fill channels, which prevents deeper drafting vessels from navigating the waterways and delivering goods.

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