When Bob Carpenter and Roger Ralph, partners in Eastern Athletic Clubs, opened their Hockessin Athletic Club in Hockessin, DE, last year, they didn't follow the traditional route of using a chlorine system for the club's four pools. Instead, they chose a salt water system because they determined it would be less expensive and easier to maintain.
So far, the choice has meant less of a chlorine smell in the building, a softer feel to the water, less skin irritation and less eye irritation because the water's salt content is similar to that of human tears, says Tito Rosa, the club's ground/pool manager.
Lauren Suleski, aquatics director of the Hockessin Athletic Club, expects the salt water system will help the club save on maintenance costs.
“The salt water system is a hefty investment for any facility to make, but once the system is in place and properly maintained, savings will start to show within a given amount of time — one to three years depending on the size of the facility and number of pools,” she says.
Until recently, operators of pools have had little choice but to use chlorine disinfection systems. Even though chlorine remains the water disinfectant of choice for most club owners, alternative treatments, such as salt water and ultraviolet light systems, are gaining popularity. However, no water disinfection system is foolproof, and state regulations often require chlorine to be used in pools even if they are salt water or use ultraviolet light.
Hockessin's salt water system uses low-voltage electrical systems to convert salt into chlorine. Chlorine generator systems contain electric cells that — because of salt being added to the water — generate chlorine continually, Rosa says. After the chlorine has done its job, it reverts back to salt to be reused again, thus allowing free chlorine to be produced and allowing it to react just as liquid chlorine would from a bucket.
Connie Centrella, program director for the online Aquatic Engineering Program at Keiser University eCampus, a division of the Fort Lauderdale, FL, campus, says that salt water systems are gaining in popularity for a couple of reasons, including reduced handling of chemicals by staff and potential savings.
“The initial installation of a chlorine generator is more than the traditional chlorine erosion feeder,” she says. “However, the process continually makes chlorine without manually adding additional tablets to a feeder. So while the initial cost is more, over a period of time they will notice a reduction in not only the cost of the trichlor tabs or hypochlorite tabs but also in the transportation costs and storage costs involved.”
The Case for Chlorine
Despite their growing popularity, not everyone is a fan of salt water systems. When the owners of La Camarilla Racquet, Fitness & Swim Club in Scottsdale, AZ, built a 25-meter outdoor swimming pool about five years ago, they opted to go with a salt water system. Initially, the decision seemed like a wise one. However, over time, maintenance requirements became a problem, particularly keeping the water chemistry balanced.
“Salt water is cheaper to operate, but the upkeep was the more costly factor,” says Roger Furman, general manager of the club. “Salt systems require much more maintenance than you are led to believe. They are much harder to regulate and keep within limits.”
Furman stopped using the salt water system about two years ago and switched to chlorine.
Rosa says he has experienced only one problem with the salt water system at Hockessin: holding the minimum salt level below a certain level tends to overwork the equipment.
Mick Nelson, club facilities development director for USA Swimming, the national governing body for the sport of swimming based in Colorado Springs, CO, says that chlorine produced from salt is extremely unstable and burns off quickly — especially when exposed to sunlight. Also, pools using salt-generated chlorine systems have to be stabilized, as pH levels tend to bounce, and maintaining proper salt content is critical.
The Maricopa County (AZ) Health Department is responsible for regulating La Camarilla's pool. Its chemical standards, listed under the Maricopa Environmental Health Code, state that “whenever chlorine, or a chlorine compound is employed for pool disinfection, the amount of free chlorine residual in the water shall not be less than 1.0 ppm (parts per million) or more than 5.0 ppm for public and semipublic swimming pools.”
In most cases, Nelson says, a state's department of public health is the primary regulatory agency for commercial pools. In some isolated cases, the state's Environmental Protection Agency is involved, and the Center for Disease Control and Prevention works closely with these entities to ensure best practices. Regulations vary by state.
“Each state is different in their regulations for the amount of free chlorine and total chlorine, and they each require a different ppm, but most levels are between 1.0 ppm and 5.0 ppm,” Suleski says. “There is no regulation difference at this point for the amount of chlorine required for the different systems. They are all the same and require the same amount.”
Seeing the Light
The use of ultraviolet light systems for water disinfection also is growing in popularity. To mitigate the odor and irritants associated with chlorine, management at the YWCA of Minneapolis is considering retrofitting one of its pools with ultraviolet light next year. Currently, the Minneapolis YW uses chlorine gas in each of its nine pools. The gas form of chlorine is acidic, with a pH close to muriatic acid, so the YW uses a base of soda ash and sodium bicarbonate to make it easier and less risky to handle.
Gas chlorine is the most effective per unit of any chlorine or halogen sanitizer, says Jason Burmeister, product coordinator for aquatics at the YW.
“It is 100 percent chlorine as compared to pellets at 65 percent and liquid at 12 percent,” he says.
The ultraviolet water system is attractive to the YW, Burmeister says, because it would be easy to add on to the current system and has minimal maintenance requirements. In addition, it would reduce the number of super chlorination sessions and help combat germs such as crypto, which infects a swimming pool through fecal matter coming into contact with water. Using ultraviolet light in conjunction with chlorine would eliminate the presence of chloramines, a chlorine compound that is more stable in the water system than chlorine and does not burn off in the water.
Chloramines smell like ammonia and can cause eye irritation and respiratory problems for swimmers and staff. High levels of chloramines can also cause corrosion issues to metal components of the pool, including ladders, handrails and a building's heating, ventilating and air conditioning system.
Indoor pools have been adversely affected by municipal water companies adding chloramines in excess of 1.5 ppm to drinking water supplies, a practice that Nelson says causes “terrific problems for indoor pools and air quality.” He says that properly designed ultraviolet water treatment systems, along with installing an activated carbon filter on the city water line that fills the pool, provides the best remedy for fighting chloramines.
One factor preventing some club owners from making the switch to ultraviolet systems is budgetary concerns.
“Funding is always an issue, and the pool stuff doesn't always register on the top priority list of the many other issues that need to be dealt with,” Burmeister says.
According to Nelson, the price tag for a medium pressure ultraviolet unit in a 25-yard, six-lane pool can range from $20,000 to $35,000. For a 50-meter pool, the price ranges from $32,000 to $70,000.
Making the Switch
Ultraviolet light systems, when used in conjunction with chlorination, lower the amount of chlorine and other chemicals while preventing harmful effects on a pool's pH balance. Not only does this technique improve the pool environment and water quality, but it also destroys chloramines and other toxic byproducts of chlorine, thus effectively eliminating the strong odor associated with chlorine, according to Patrick Wolf, facilities coordinator for the Baylor Tom Landry Fitness Center.
A persistent odor was the driving force behind why management at the Landry Fitness Center switched from a traditional chlorine disinfection system to an ultraviolet light water treatment system for its two pools. The facility, which consists of three floors, had been permeated with the distinctive aroma of chlorine.
“It used to be when you walked in the building, you could automatically tell there was a pool in the building,” Wolf says.
Prior to switching to the ultraviolet system in 2002, the center had used a chemical chlorine enhancer in an attempt to eliminate the smell in the building. However, the enhancer caused people's skin to itch. One of the primary benefits of an ultraviolet system, Wolf says, is that swimmers' skin does not become irritated. The Landry Fitness Center, located in Dallas, uses the minimal amount of chlorine required by Texas state law: 1.2 ppm.
In addition to being easier on a swimmer's nostrils and skin, ultraviolet light provides substantial benefits to the fitness center in the form of reduced expenditures. Wolf estimates that the ultraviolet light system cuts costs for chemicals by two-thirds while maintaining ideal water chemistry levels.
The system cost the Landry Fitness Center approximately $30,000 to install. The average annual maintenance cost, which includes replacing pressure bulbs that go out about once a year, is roughly $2,000, a figure Wolf characterizes as “relatively nothing in the pool industry.”
Although both ultraviolet systems and salt-generated chlorine systems combat chlorine odor and reduce irritation to swimmers, Nelson favors the ultraviolet system for a number of reasons, including its ease of maintenance and ability to fight chloramines.
In the future, Nelson expects more public pools to transition to ultraviolet light.
“I don't think they will really have a choice if they want breathable air indoors,” Nelson says. “The municipalities and their chlorination of source [city] water make this a necessity.”
How to Choose The Best Treatment
Traditional chlorine disinfection systems, salt-generated chlorine systems and ultraviolet light systems each have their proponents. So what's best for your facility? It depends on a number of factors.
“When looking at new types of sanitation, you can't just base it on the number of gallons in the pool. You need to base it on the environment: Is it indoors or outdoors? What is the water temperature? How many people use the facility?” says Connie Centrella, program director for the online Aquatic Engineering Program at Keiser University eCampus, a division of the Fort Lauderdale, FL, campus.
Before choosing a pool system, club owners should research and consider all options.
“Evaluate your specific pool and water needs,” says Lauren Suleski, aquatics director of the Hockessin Athletic Club in Hockessin, DE. “Gather information from facilities that use the various types of sanitizers, and see which one is best for your budget and the needs of your patrons.”
The most important factor to consider? The safety of swimmers.
“The primary goal of every aquatic facility manager is to provide a safe environment for those who get in the water, to prevent recreational water illnesses and contamination, and to maintain a water condition that will ensure user comfort,” Centrella says.
Roger Furman, general manager at La Camarilla Racquet, Fitness & Swim Club in Scottsdale, AZ, adds, “What works for you and keeps you open and safe is the way to go.”