Columbia Slough - History - World War II and After

World War II and After

After the start of the war with Japan, President Franklin D. Roosevelt signed an order for internment of all the people of Japanese ancestry who lived on the West Coast. About 1,700 of them lived in Portland, and some had farms or businesses near the slough. When the government removed them from their homes in 1942, it housed them temporarily in the Livestock Exposition Center (Expo Center) in Kenton before sending them to internment camps further inland. They were not allowed to return until 1945.

In 1942, Kaiser Shipbuilding Company began making ships for the war at three huge installations near the lower slough, one in St. Johns, one on Swan Island in Portland's Overlook neighborhood, and one in Vancouver, Washington. St. Johns and Vancouver made Liberty ships, while Swan Island made tankers. The St. Johns shipyard became the nation's leading producer of Liberty ships. To house shipyard workers and their families, Henry J. Kaiser bought 650 acres (260 ha) of former marsh, pasture, and farmland in the lower slough watershed surrounded on all sides by dikes between 15 and 25 feet (5 and 8 m) high. Here he built a new city, at first called Kaiserville and later Vanport. By 1943, Vanport's population of 39,000 made it the second largest city in Oregon and the largest wartime housing project in the U.S. After the war, the population fell to about 18,500. This was roughly the number of people living there on May 30, 1948, when a flood broke through Vanport's western levee. The break occurred during the afternoon of a day with mild weather. The first rush of water soon became a "creeping inundation", slowed in its advance for 35 to 40 minutes by water-absorbing sloughs. The water's gradual rise within the city allowed most of the residents to escape drowning. The county coroner's official list of bodies recovered was set at fifteen, and seven people on a list of missing people were never found. The flood destroyed the city, which was never rebuilt.

The Vanport flood induced changes to the slough's system of levees, which were rebuilt and in some cases fortified to withstand a 100-year flood. Instead of repairing the levee along the Peninsula Canal, the city plugged it at both ends. The disaster also affected Oregon's system of higher education. After floodwaters destroyed the Vanport Extension Center, set up in 1946, the Oregon Board of Higher Education reestablished the school in downtown Portland, where it eventually became Portland State University.

Debate about how to use the slough and its watershed continued through the rest of the century. In 1964, the Port of Portland, interested in industrial development, began to fill Smith, Bybee, and Ramsey lakes with dredge sands from the Columbia. In the 1970s, the Oregon Legislature passed a law against filling Smith or Bybee lakes below a contour line 11 feet (3.4 m) above mean sea level except to enhance fish and wildlife habitat. Plans for a Willamette River Greenway project proposed by Oregon Governor Tom McCall in the late 1960s called for park and recreation areas along the Willamette and many of its tributaries but ignored the slough. Some planners argued that the slough was so filthy that more industry was all it was good for. They portrayed cleanup as a lofty but impractical goal.

At Oregon's request, the U.S. Congress stripped the slough of its navigable status in 1978. This ended channel dredging on the slough, which could then be used for recreation. Other laws affecting the slough in the 1970s and beyond were the federal Clean Water Act and the Oregon Comprehensive Land Use Planning Act. In 1986, a business association began promoting commercial development along the upper slough, and the city later used urban renewal funds to support industrial projects near the airport. In 1996 the city acquired the Whitaker Ponds Natural Area, where it began a slough watershed education program for children.