Feature Article - February 2007
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Special Supplement: A Complete Guide to Aquatic Centers

By Jessic Royer Ocken


For filtering your pool, your options are essentially the standards that have been available for a number of years, and if you have an older facility, you're likely already familiar with one of the following: Most commercial pool filtration systems use sand, cartridge-style filters or diatomaceous earth (DE) filters, which are definitely made of the coolest material—the fossilized skeletons of itty-bitty creatures.

Each generally works by drawing unfiltered water into the filter and sending filtered water, free of organic material and many bacteria, out the other side. As the filter fills up with debris, the pressure in the system rises, and you know it's time to clean things out.

Filter systems, especially the DE variety, can capture some remarkably small bacteria, and hopefully anything that zips through will be zapped by the sanitation system you have in place (more on this below) in short order. Over time, however, a few of the more wily germs have developed ways to elude chlorine, and if you don't have other sanitation options at the ready, your pool may have a problem.

To combat this situation, consider adding a coating to your filters. Coatings give your filter a positive charge, which helps it grab bacteria and viruses (that tend to have a negative charge) like a giant magnet. The Environmental Protection Agency recently approved a new particle-removal system product that even helps your filters contain the evil cryptosporidium—notorious for causing nasty illness outbreaks at sprayparks—as well as algae and E. coli.

Crypto germs come contained in a handy chlorine-resistant shell, so your best bet is to filter them out of the water altogether (or prevent them from getting there in the first place—see the section on safety for more on this). This improved ability to remove debris and germs from water also yields a clearer, less cloudy pool, and these products work with many existing filter systems.

But about that sanitizing. This is, of course, your other main line of defense against debris, disease and other potential water nastiness. The majority of pools still use chlorine, either gas or liquid, but even those old-school facilities can adopt an automated chlorine-delivery system. Automation helps regulate water chemicals and can mean less chlorine use and less labor for your staff.

Open to All

As you work toward your goal of making your aquatic center as broadly appealing as possible, make sure your facility is able to welcome all who want to attend.

A submergible stairway will ease entry and exit from the pool for seniors and those with disabilities, and wide walkways and doorways make wheelchairs easier to maneuver.

Pay particular attention to your bathrooms and locker rooms, as these are often areas without a lot of extra space. Cram things too close together, and you'll make it impossible for a portion of the population to use your facility.

Whether it's a full-sized pool, a hot tub or a wading pool, "more organizations, states and counties are requiring automatic feeders," said Tom Lachocki, president of the National Swimming Pool Foundation (NSPF). "When you have automatic controllers and feeders, health codes allow those facilities to test the water manually less frequently, so you save on manpower. You do water chemistry to keep things sanitary based on present conditions and be sure you're not spreading infectious disease. No water is sterile that has people in it, but when you control the pH you make sure the pool has a greater likelihood of being compliant with water standards."

For those able to look toward the cutting edge, there are some other sanitizing options gaining ground on chlorine's market share. Salt-chlorine generators produce the tried-and-true pool-disinfecting substance (chlorine), but they create it by breaking down salt. At the end of the process, any leftover chlorine returns to the salt format. One manufacturer described the process as passing salt ions over specially coated blades, then adding an electrical charge, noting that salt-chlorine generators are by far the most popular means of sanitizing pools in Australia. In many cases salt is a cheaper substance to acquire than chlorine—and less hazardous, too.

Another alternative is an ozone system. Long used to sanitize municipal water, ozone can greatly reduce the amount of chlorine required when it is used as part of your pool-sanitizing mix. "We don't advocate ozone alone, but we have found that when you use ozone in combination with chlorine, you can use a lot less chlorine. In some cases you can reduce it by as much as 80 percent," explained Kevin Caskey, a microbiologist who works with a manufacturer of ozone systems for swimming pools.

"Ozone is a great disinfectant. It kills [germs] and destroys a lot of things quickly. It just penetrates the cell wall of bacteria and destroys it," he said.

With such a system, pool water passes through tubing where it is mixed with tiny bubbles of ozone and disinfected. But after doing this work, ozone doesn't hang around in the water like chlorine does, so you need a bit of chlorine as a second line of defense. However, with a lot of the water's organic contaminants (sweat, urine, fecal matter) knocked out in this initial treatment, the remaining chlorine has less to do. It takes a bit of new plumbing and some extra equipment to add an automated ozone system to your pool, but in the long run, you might decide it's worth it.

Other newer types of sanitizing systems use ultraviolet light, minerals or silver and copper ions to kill bacteria, but you should consult with your pool's designer and maintenance staff to determine what's best for you.

"At Burbach we tend to recommend filtration systems that are easy to maintain, with fiberglass or plastic components," Burbach noted. "With disinfectants there are many styles and concepts. Some people say chemicals are the only way to go. Others say to use UV and ozone generators. There are lots of methods, but primarily we still rely on very proven and easy-to-maintain systems."

If your staff is mostly seasonal and relatively inexperienced in pool sanitation, ease of use may be your primary concern. However, with a more experienced year-round maintenance team in place (and perhaps a larger budget), you may have your pick of systems.