Activities Sports & Athletics Fascinating Facts About Pools, Spas, Swimming and Safety Share PINTEREST Email Print Sports & Athletics Swimming & Diving Gear Workouts Health & Safety Technique Diving Baseball Basketball Bicycling Billiards Bodybuilding Bowling Boxing Car Racing Cheerleading Cricket Extreme Sports Football Golf Gymnastics Ice Hockey Martial Arts Professional Wrestling Skateboarding Skating Paintball Soccer Table Tennis Tennis Track & Field Volleyball Other Activities Learn More By Lisa Hallett Taylor Lisa Hallett Taylor is a writer and editor with 12+ years experience covering architecture, landscape design, and do-it-yourself projects. our editorial process Lisa Hallett Taylor Updated January 29, 2020 Just how many pools and hot tubs are in the United States? What percentage of the country's population goes swimming during a given year? And, for those who like to be informed or are germ-obsessed, which of those recreational water infections lurking in our waters is most prevalent? We've compiled facts and statistics from the U.S. Centers for Disease Control and Prevention (CDC), Association of Pool and Spa Professionals (ASPS), and the United States Census Bureau to enlighten and address any questions you might have related to swimming, safety, and even pool construction. Arming yourself with knowledge will help in making smart decisions related to recreational water activities. 01 of 13 How Many Pools Are in the United States? David Sucsy/Getty Images There are 10.4 million residential and 309,000 public swimming pools in the United States, according to the Association of Pool & Spa Professionals (APSP). As you can imagine this leaves thousands of possibilities for world records; From the largest wave pool to the deepest pool for diving. 02 of 13 How Popular Is Swimming in the United States? Ojo Images/Getty Images Swimming is the fourth most-popular sport or activity in the U.S. No. 1 is walking, while the No. 2 spot goes to exercising with equipment, according to the U.S. Census Bureau. One of the many reasons people love to swim is because it's such a good exercise for weight loss. 03 of 13 The Top 5 States for Above-Ground Pools AleksandarGeorgiev/Getty Images While the portability of above-ground pools connects them with states in which owners use them solely during the summer, that's not always the case. The five states that report the highest number of above-ground pool sales and installations are: CaliforniaTexasFloridaOhioIllinois 04 of 13 The Top 5 States for Hot Tub Installations Mint Images/Getty Images Oh, those Californians with their neutral-toned fruitwood chairs and Sonoma County merlots. Of course, they'd be number one in the hot tub category. Here are the top five: CaliforniaTexasFloridaIllinoisNew York 05 of 13 The Top 5 States for In-Ground Pools Getty Images It won't come as a surprise that sun-drenched and most populous states report the most in-ground swimming pool installations. The top five are: CaliforniaFloridaTexasArizonaNew York 06 of 13 How Many Adults and Kids Swim Annually? Fuse/Getty Images According to statistics, 36 percent of children aged 7 to 17 years, and 15 percent of adults go swimming at least six times annually in the United States. Swimming isn't restricted to residential and public pools. About 91 million people over the age of 16 swim in oceans, lakes, and rivers each year in the United States. 07 of 13 Kids and Teens Lisa Hallett Taylor This may come as no surprise but swimming is the most popular recreational activity for children and teens (ages 7-17). 08 of 13 Water Safety Through Swim Lessons Westend61/Getty Images Swimming lessons aren't just "something to do" during the summer. The goal of lessons is to make children and adults safer in and around the water, according to the USA Swimming Foundation. Among the organization's findings: In households with incomes of less than $50,000, 79 percent of children have minimal or no swimming ability.An average of 10 people drown each day in the U.S.Swimming lessons from a certified instructor, school, or organization reduce the incidence of childhood drownings by 88 percent. 09 of 13 How Many Hot Tubs? Photo © Jacuzzi There are more than 7.3 million hot tubs in operation in the U.S., according to a study conducted by Pool and Spa Marketing. 10 of 13 Swimming With Diarrhea Sarah Small/Getty Images You may think that swimming with sharks poses a danger, but swimming with diarrhea can pose a real threat to those around you. So, if you're experiencing a bout of it, do everyone a favor and stay out of the pool until your tummy has resolved itself. More than 1 in 5 (21.6 percent) of American adults aren't aware that swimming while sick with diarrhea can contaminate pool water and make other swimmers sick. 11 of 13 How Many Spa Closures? Photo/MGM About half (56.8 percent) of hot tubs and spas are in violation of local environmental health ordinances, and about 1 in 9 spas require immediate closure (11 percent), according to the U.S. Centers for Disease Control (CDC). 12 of 13 Beware the Crypto KATERYNA KON/SCIENCE PHOTO LIBRARY / Getty Images Cryptosporidium (or Crypto) is an extremely chlorine-tolerant parasite that can survive in a properly chlorinated pool for 3.5 to 10.6 days. Of 49 recreational water-associated outbreaks of gastroenteritis from 2009 to 2010, 55 percent were caused by Crypto. Of 57 gastroenteritis outbreaks associated with treated (for example, chlorinated) recreational water venues, 84 percent were caused by Crypto. 13 of 13 How Long Does It Take for Chlorine to Destroy Germs in a Pool? Philippe TURPIN / Getty Images Chlorine kills most bacteria such as E. coli in about a minute if it is maintained at proper disinfection levels (1 to 3 parts per million [ppm] free chlorine) and under ideal water conditions (pH at 7.5 or less; temperature at 77 F/25 C or more) throughout the pool. However, a few germs are moderately (Giardia and Hepatitis A) to highly (Cryptosporidium) chlorine-tolerant.