For a service technician accustomed to working on residential and small commercial sites, the first Olympic account can seem like a major step up.

These pools range in size from 100,000 to upwards of 400,000 gallons — often with bather loads to match. Still, much of the equipment and chemistry isn’t all that different from that of a smaller pool — and the distinctions tend to center more on logistical hurdles than unique principles.

Here, we talk with veterans of competition pool service, and compare their experiences working on Olympic-size pools with common practices in residential and small commercial pool service. Their insights offer a clear sense of what’s different — and what’s the same — about taking on a site of this scale.

Chemical principles

Service experts agree that when it comes to working with an Olympic-size pool, the biggest difference is time — and not just the time investment necessary for proper service.

“Changes in chemistry, water levels and so on don’t happen as fast as in a smaller pool, unless you have a catastrophic event,” says Dave Hutner, aquatic director for Butler County, Pa. “So you often don’t get to see the effects of your adjustments right away — you’ve got learn to precisely anticipate what’ll happen after you leave the site.”

That means it’s crucial to record data carefully, and check existing records with a similarly keen eye for detail. At the same time, large commercial sites often have strict reporting guidelines in place, so chemical and equipment adjustments can be made with a clear idea of what effects similar actions have caused in the past.

For example, if the filter media is clogging up more quickly than usual, this might indicate that the media needs to be changed out — but by checking records of recent bather loads, it might also be possible to correlate the increased clogging with a rise in swimmer traffic over the past month, and to notice that this trend is common early in the swim season. This level of detailed documentation is unlikely to be available for a residential or small commercial pool — but at an Olympic-size site, it can help head off small problems before they snowball into larger ones.

Along with more detailed documentation, though, these sites often bring their share of high expectations. “It’s amazing how sensitive people can be to the temperature of the water,” says John Mangan, property director for the Ambler, Pa., YMCA. “Some come to swim every day, and they can tell you when it’s one degree above normal.”

What all this means is that it’s vital to test and document water variables like temperature, free chlorine and pH on a daily basis, and calculate the Langelier Saturation Index value at least once per week, to prevent problems from beginning to accumulate. “This isn’t a residential pool, where you can test the water chemistry whenever it’s convenient,” Mangan says. “You need to be checking it on a consistent schedule.”

Still, as long as measurements and adjustments are made regularly, it shouldn’t be necessary to devote more service calls to an Olympic-size pool than to any other. In fact, due to the leisurely pace at which the water chemistry of these pools changes, many techs say checking on them more than a few times a week may not serve much of a purpose.

Equipment adjustments

What holds true for chemistry is also true for equipment: It’s not so much the principles that change as it is the scale. On Olympic-size pools, a 1-hp pump may be replaced by several pumps with 15 hp, and the filter may hold hundreds of pounds of sand or D.E. Thus, it’s helpful to plan equipment service calls well ahead of time whenever possible, and bring along one or more pairs of helping hands.

“Think of it as being like the difference between working on a small car and working on a semi truck,” Hutner explains. “The equipment mostly does the same stuff — just on a much larger scale.”

In terms of piping, 4-inch and even 6-inch diameters are common — and these larger sizes typically have costs to match. This means it’s crucial to budget for such replacements, and be prepared to order them from the distributor in case of a leak or breakage.

When it comes to pumps, motors and impellers, logistical concerns can become as significant as costs. The size and weight of a 15-hp motor means a swap-out is at least a two-person job — one that may even require some out-of-the-box thinking. “It got to be such a nightmare to lift our motors up to where they needed to be for us to work on them,” Hutner says, “so we actually built a crane — a lifting system — that allows us to maneuver them into and out of position.”

Even chemical feeders — devices known for their time-saving features — can present some confusing questions to techs used to dumping chemicals directly into the pool. Because Olympic-size pools demand hundreds of gallons of chlorine per month, barrels are often stored in a room designed for that purpose, and chlorine is frequently siphoned directly from the barrels into the circulation system. While this can eliminate some logistical hurdles, it also means a lone tech doesn’t have the ability to adjust chlorine levels by hand. This is one more reason why it’s crucial to stay on top of the pool’s chemical parameters, and make careful adjustments via the control panel.

Maintenance tips

Though an Olympic-size pool doesn’t necessarily require more frequent service than any other, it’s still important to keep some unique principles in mind when arriving on site for a scheduled checkup. The most central of these is to come prepared.

“For example, I’ve got to have storage for 300 gallons of chlorine on site,” Hutner says. “I can’t just assume I’ll be able to pour it in by hand, or suck it out of a 5-gallon tank.”

Though the site’s existing management will often have strategies in place to deal with logistical hurdles like these, that in itself often makes for less flexibility in a pool’s maintenance regimen. In other words, to add enough of a chemical to make a noticeable difference, it’s necessary to plan ahead in terms of supplies and on-site space, because a quick dash to the distributor isn’t likely to be sufficient.

It’s also helpful to devote more time to vacuuming and scrubbing in a pool this size. Though there are automatic cleaners designed for large pools, service veterans say there’s no substitute for regular, thorough scrub-downs — especially for outdoor pools where algae can thrive.

“We do a lot more brushing than in smaller pools because I don’t want algae to take hold even a little,” Hutner says. “It can get to be a real hassle to deal with in a pool of this size.”

Further complicating this issue is the fact that extremely large pools are prone to develop “dead spots” — areas where the water doesn’t circulate as actively as in other parts of the pool. This makes brushing all the more important, as it helps circulate sanitizers and algaecides through these areas.