The Port of Portland employed the PORTLAND, a wood-burning, steam-powered dredge. It was joined in 1902 by the Columbia I, almost three times as powerful. A third dredge, the WILLAMETTE I, was launched in 1913. The TULATIN went to work in 1916, the COLUMBIA II in 1921, and the CLACKAMUS in 1925.
The OREGON, launched in 1965, not self propelled and requiring a considerable attendant plant, including a 65' towboat, a 55' power barge, a 35' crew boat launch, five anchor barges, over 18,000 ' of pipeline, a water barge, and a fuel barge. This was the dredge operating when Mount St. Helens erupted and dumped a load of ash, sand, and debris of biblical proportions into the Toutle River, that feeds into the Cowlitz River––a tributary of the Columbia that enters at Kelso–Longview, WA. The flood of volcanic material raced down he mountain at 30 miles per hour and into the rivers, forming a shoal of sand debris all the way across the Columbia's navigation channel. For a space of 7 miles, the remaining channel was only about 15' deep; the day before the eruption, it had been 40' deep. Ships were stranded on either side of this dam; those in Kalama, WA and Portland could not leave, and those downstream couldn't move upriver.
The dredge OREGON and the US Army Corps of Engineer's three hopper dredges went to work, and in five days they had cleared a channel wide and deep enough for small ships to pass. It took them six weeks to return the channel to its normal 40' depth and 600' width.
One benefit of dredging is the new land created by the dredge spills. All along the river between Portland and Astoria are new islands, beaches, and industrial sites. These include Rivergate Industrial District, Swan Island Industrial Park, Port of Portland terminals, Portland International Airport, and similar areas near Vancouver, Kalama, Longview (all in Washington), and Astoria."
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Archie Satterfield & Walt Crowley. Seattle; Sasquatch Books. 1992.
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