[2] Vanport construction began in August 1942 to house the workers at the wartime Kaiser Shipyards in Portland and Vancouver, Washington.

Vanport—a portmanteau of "Vancouver" and "Portland"—was home to 40,000 people, about 40 percent of them African-American, making it Oregon's second-largest city at the time, and the largest public housing project in the nation.

[4] Vanport was dramatically destroyed at 4:05 p.m. on May 30, 1948, when a 200-foot (60 m) section of a railroad berm holding back the Columbia River collapsed during a flood, killing 15 people.

The lack of businesses and recreation opportunities contributed to a sense of distrust, and the relative isolation of the largely male workforce meant there was little demand for community institutions such as a newspaper or high school.

[3] The establishment of Vanport coincided with an unprecedented influx of African-Americans into Oregon, attracted to work in newly federally-desegregated wartime defence industries.

Due to exclusionary racial laws, the state had a population of fewer than 1,800 Black people in 1940; by 1946 more than 15,000 lived in the Portland area, mostly in Vanport and other segregated housing districts.

White migrants from the South were the most vocal in opposing the degree of integration that HAP dictated for schools, buses and work sites.

Reacting to the criticism—and pressure from Eleanor Roosevelt—by April 1944, HAP began placing incoming Black people into the "white" areas of the settlement.

Entire buildings were free in the "Black" areas of town, they argued, and after opponents of the integration plan appeared at a HAP meeting the authority decided to resume its previous policies.

Critics attributed the poor response, in both cases, to racist attitudes on the part of officials, who pointedly neglected to respond appropriately to the destruction of a community that had a relatively large number of Black residents.

On the morning of Memorial Day, May 30, 1948, the Housing Authority of Portland issued the following statement: "Remember: Dikes are safe at present.

"[18][19] At about 4:17 p.m. the Spokane, Portland and Seattle Railway berm burst,[17] sending a 10-foot (3 m) wall of water into the area of Vanport College.

[20] Because of the numerous sloughs and backwaters in the area, the progress of the flood was delayed about 30 minutes, giving residents more time to escape.

Vanport, argued National Urban League director Lester Granger, was a "nasty, segregated ghetto" where "negroes lived in the same patterns as they did in the South.

"[citation needed] The flood that wiped out the district, he continued, was a benefit in that it allowed Black people to further integrate into Portland's society.

[25] To prevent future incidents, Congress enacted the Flood Control Act of 1950 which spawned projects such as the Priest Rapids Dam.

The loss of Vanport is considered a factor in the eventual closing of the Jantzen Beach Amusement Park on Hayden Island in 1970.