Swimmers enjoying their first laps of the season in public pools on Memorial Day can thank the naked working-class boys of the Victorian era for the luxury.

The country's municipal pools, in fact, were first constructed to get rowdy, scantily clad youths out of the rivers and lakes and away from the public eye. They also served as large bathtubs for poor and immigrant neighborhoods.

In his new book, Contested Waters: A Social History of Swimming Pools in America, historian Jeff Wiltse traces the evolution of municipal pools in America from the late 1860s to today. Focusing on northern cities like Chicago, Milwaukee, and St. Louis, Wiltse finds that pools gradually became hotbeds of social change.

Originally pools were melting pots where blacks, whites and immigrants interacted. Men and women, however, swam on separate days.

The dynamics changed after World War I. Pools went from bathhouses to leisure destinations, complete with sand and chairs for sunbathing. Cities across the country joined in a construction craze, building pools like Fairgrounds Park Pool in St. Louis that could accommodate thousands of swimmers at a time.

As a recreational refuge, pools became prime destinations for families. Men and women interacted in the water for the first time, and Wiltse found that the change spawned a wave of racial segregation across northern pools: Whites were mainly concerned about black men interacting with white women — they feared the sexual atmosphere at a pool might promote racial mixing.

Wiltse examines how whites enforced segregation, and how blacks fought back. He tells Jacki Lyden that while municipal pools have been officially desegregated, they have yet to fully integrate.

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