Swimming Pools and Spas

The swimming pool, and to a lesser extent the spa, has long been a symbol of affluence and a critical amenity for hotels and resorts. Swimming for fitness is common at schools, health clubs, and military installations. According to the U.S. Census Bureau, swimming is the second most popular recreational activity—behind walking—in the United States. Residential swimming pools were a $6.9-billion industry during the first decade of the 21st century. Many people believe that the ancient Romans invented the swimming pool, but they were actually latecomers to the idea. The earliest known sacred baths date to about 3000 b.c.e. in the Indus Valley, [Page 893]and the ancient Greeks built swimming pools near their gymnasiums. Although “taking the waters” at fashionable spas had long been an activity for the affluent, modern swimming pools were introduced to the Western world by the British, who during the 1800s had experienced public baths in India and the Far East.

In many coastal cities, floating baths provided swimming facilities. These were simply barges moored alongshore with open bottoms. Changing rooms, benches, and diving boards surrounded the swimming area. In the polluted harbors of the era, exposure to floating sewage limited their popularity. Nonetheless, Boston, Massachusetts, operated 14 such facilities in 1901, along with 10 municipal beaches and two swimming pools. The first municipal swimming pool in the United States was in Brookline, Massachusetts, in 1887. During the 1890s, a hygienic reform movement in the United States encouraged cleanliness through regular bathing and exercise through swimming. Swimming as a sport gained popularity after the first modern Olympic Games in 1896. By the 1920s, there were several thousand public swimming pools in operation; about two-thirds were operated by Young Men's Christian Associations (YMCAs), colleges, schools, Boys’ Clubs, and the remainder were commercially operated.

If swimming pools are drained into ponds or lakes, the chlorinated water can harm aquatic ecosystems. Almost all sterilizing agents must be disposed of as hazardous wastes. Chlorine can react with organic materials in drinking water to form carcinogenic compounds.

Prior to World War II, private, in-ground pools were reserved for the wealthy. A typical 20-by-40-foot residential pool cost at least $8,000 on the West Coast and more in the eastern states. The technology to apply concrete pneumatically was introduced in 1940 and cut the cost of a residential pool by as much as 75 percent. By 1963, advances in construction techniques lowered the price of a residential pool to an average of $4,000. By the mid-1980s, there were 2.6 million in-ground residential pools in the United States and an additional 2 million above-ground pools. Twenty years later, 8 million families owned a swimming pool, and there were an additional 5 million spas.

During the first decade of the 21st century, the average size of residential pools declined by 14 percent. In the early 1990s, 40 percent of new pools were 30,000 gallons or larger, and fewer than one-third were 20,000 gallons or smaller. However, as house sizes increased, the available land for pools and other outdoor amenities decreased.

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