Contested Waters: A Social History of Swimming Pools in America

A compelling read that surveys the sociology of public swimming in the United States, and notably captures the reasons behind the advent of racial segregation in aquatic facilities, and its demise. It's an academic book, yet written without obscurant language (in other words, it's easy to read!)

The book has a regional bias (as I recall -- I read the book several years ago, there is no or scant discussion of west coast facilities, including the famous Sutro baths in San Francisco) but it’s a great addition to pool libraries replete with coffee table monographs and little else of substance.