Event 74 years ago in late May affected large portion of Pacific Northwest, but would be almost impossible today

On May 30 and 31, 1948, flood dikes protecting Vanport were threatened and a railroad fill, which served as a dike, ultimately failed.COURTESY PHOTO: OREGON HISTORICAL SOCIETY - People viewed damage caused during the Vanport flood in 1948 that destroyed a town of more than 20,000.Jerry Herrmann

A settlement of more than 20,000 people in Portland, Vanport was the invention of great industrialist Henry Kaiser as he sought in the early 1940s to build ships for Great Britain, our countries and our allies with the intent of winning World War II in Europe and the Pacific. Portland and Vancouver, Washington, were chosen for the sites of Kaiser's mass production of Victory Ships, which led to the need to house and equip a whole new community on the Oregon side of the river. Workers from all over the country are welcome and employed in the important effort while living in Vanport.

The newest city (though never incorporated in Oregon) became the community called Vanport, built in lowlands adjoining Smith and Bybee lakes, Willamette Slough and the Columbia River.

The community had its new "shopping center" concept where residents could buy whatever they needed, its own theater and importantly parks where young and old could recreate adjoining Willamette Slough. The elevation of the land was generally less than 15 feet above the Columbia and thus was protected by dykes and railroad fills.PMG FILE PHOTO - This is the railroad embankment doing double-duty as a levee that failed in 1948, destroying the nearby city of Vanport.

In winter and spring 1948, a major accumulations of snowpack clear up into Canada, and then the emergence of April and May rainfalls, began huge runoffs all the way to Vancouver, British Columbia. On the Frazier River and of course many upper Columbia tributaries that were undammed at that time things went wild. The only dams in existence were Grand Coulee and Bonneville. Those dams were not in any way capable of dealing with any runoffs in earnest that began in mid-May and culminated at 30 feet above summer low water in Vancouver and Portland on the Columbia.

Some say the Vanport flood of 1948 is what we remember. But in fact, the entire region, clear up into Canada, including the Frazier River valley and delta were all flooded in a never-to-be-forgotten runoff event.

Hundreds ran for their lives as walls of water poured through vast areas that are now Portland International Raceway and Delta Park, etc. Ultimately, less than a hundred people died, but the city, which at that point, had even become "Vanport College" went away. Vanport College was later rebuilt at Portland's Lincoln High School as Portland State University. But Vanport, as a city, was gone for good.

With our larger than normal snowpack and heavy April and May rains, what can we expect? The National Weather Service, river forecast centers operated with NOAA and the National Weather Service point out that huge storage dams, in Canada and on our border, serve to store huge runoff events that ran "helter skelter" in the 1940s. Over a million cubic feet per second cascaded from the Grand Coulee and Bonneville dams at that time. Today's forecasters speak about the International Water Treaties that exist now between Canada and the United States. "If these governing agreements and new storage dams had existed in 1948, the great floods would've been improbable in our 2000s," today's forecasters state.

But as a child, my father took me to our riverbank in West Linn and showed me the river barely 10 feet from going over the bank at elevation 35. At that time, Willamette Falls would have been barely a falls at all with about 10 feet of drop. Historically, salmon and steelhead and even large mammals were helped to bypass the falls by these great historic backwater floods. The falls were not the obstacle they are today to fisheries. There are even records in 1948 of sea lions passing over the falls and proceeding south to plug up the work at Salem's Methodist Mission Mill in downtown Salem. Near Oregon City, sea lions were seen on agricultural lands and in some cases stunned farmers when they came out to pasture lands to witness cows "which were not of their kind."

It is unclear the expected height of this year's "backwater" but it should be sizable, but not that of Vanport of 1948. Whatever the case, it is the most beautiful time to be on our Willamette because it becomes a lake. It is peaceful like a lake and fish and people can roam along what would be otherwise exposed banks to view fish and wildlife activity as the backwater inundates otherwise dry landscapes.

Oregon City, West Linn, Lake Oswego, Gladstone, Milwaukie and Portland are all affected by Pacific Ocean tides all the way to Willamette Falls. This is what makes our part of the region so unique. We are also affected by the annual backwater events of the Columbia when our Willamette becomes a beautiful and pristine lake.

Jerry Herrmann is president of Rivers of Life Center, a nonprofit organization that serves at-risk youth throughout the Willamette Valley.

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