It's time for traditional pool winterizing practices to evolve

Terry Arko Headshot

Any parent of small children knows that when you put your child to bed for the night, you will at some point need to check and make sure that they are settled and asleep. When you winterize a pool you are in a sense putting it to bed for the winter. However, most pool professionals put their pools to bed and forget about them until the next spring. In today's world, it might be wiser to check on the pool before it's time to wake it up in the spring - to avoid challenging pool openings.

In areas where winters are severe, it is common practice to open and close pools by the calendar - usually Memorial Day and Labor Day form the bookends of the season. Once the pool is winterized and covered it is pretty much forgotten until spring.

However, in light of current climate changes, traditional winterizing may need to evolve. Systems for closing down a pool based on temperatures rather than by the calendar should be considered. In addition, because chemicals are consumed faster when temperatures are warmer, it may be prudent for service pros to consider incorporating follow-up visits to the pool when temperatures rise.

Traditional Winterizing

Winterizing differs depending on what region of the country the pools are in. The Northeast experiences hard freezes, and several important steps are needed to keep the pool protected during these periods. First, the chemical balance needs to be checked and adjusted as needed: pH should be 7.2 to 7.6; total alkalinity should be between 80 to 120 ppm, calcium hardness 175 to 250 ppm. Pools should be super-chlorinated or dosed with a chlorine-free shock. After shocking, allow chlorine levels to come down to between 1.0 to 3.0 ppm and then add a winterizing algaecide.

Other duties include partially draining water, blowing out all above-water lines with air, plugging all returns and drains, adding a pool-grade antifreeze and covering the pool. Once this is done the pool is typically forgotten until time for a spring opening. In milder regions, pools may be covered with a mesh cover (or not), then chemically treated while filtration time is reduced.

Until recently, these traditional winterizing methods have worked fairly well. But weather patterns have definitely changed, leading to warmer fall seasons, shorter winters and early springs.

As a result, pool professionals across the country have reported their pools are filled with much more algae and are very difficult to get into shape for swimming. A growing number of pool professionals are now opting for new ways to close and open pools because of these challenging openings.

Steve White with UnderWater Pool Masters in Massachusetts has changed his closing and opening routine with recent changes in weather patterns. "We have definitely changed our winterizing program in the last few years because of warmer weather here in the Northeast. We find that with increased rain and warmer weather in March and April, the pools open with a real algae challenge. Since most of our pools have safety covers, the mesh material allows rain water and nitrates to enter the pool water, and with a little sunshine and temperatures above 50 or 55 degrees, the pools are filled with algae by the time you open in May."

With fall staying warmer longer some residential pool owners may choose to keep the pool open longer. One problem that can occur in these situations is the falling leaves in many regions. Ginny Mulvaney, president of Custom Pools in Minnesota says, "We actually try to encourage people to keep their pools open longer, but with the leaves that come down in the fall, a pool can be covered with leaves in one hour or less. It can be just too much work for the homeowner."

A short winter, an early spring and lots of leaves in the pool can lead to heavy algae and staining problems at opening time. Leaves left in pools over the winter and into spring hold algae spores that release stains from tannins on the pool surface.

Warm Weather Contingencies

Many pool professionals are incorporating contingency plans to deal with warmer weather patterns and earlier spring openings. "What we now offer is what we call a 'Chemical Drop' - a pre-opening service for both our residential and commercial customers," says White. "This service involves adding five gallons of liquid chlorine and one quart of algaecide to arrest the algae growth. This keeps the algae from growing so we don't have to battle algae in late May. We even recommend this to customers who are treating pools themselves."

Others, such as Mulvaney of Custom Pools, will start to prepare for warmer springs at closing time. "Our main focus at the end of the summer is to heighten the awareness of customers about the importance of having to use extra chlorine and extra algaecide before closing, to hopefully help with the spring openings. But again, you just don't know what kind of winter we might have." These professionals have become keenly aware of changing patterns and understand the importance of checking on pools both late and early to ensure easier openings.

Late Fall Checkup

Warmer seasons may be conducive to doing a late fall checkup; pool professionals should consider adding chemicals in cases where an Indian summer has stretched into November. This goes back to the analogy of checking on the children after putting them in bed. A good checkup includes testing the water balance and chlorine levels, adjusting as needed and adding algaecide.

One beneficial treatment that can be done both early fall and spring is to treat for phosphates. White says, "So we still follow the rule of closing our pools 'clean' - super-chlorinating, removing all nutrients (using a ton of phosphate remover) and providing our 'pre-season' treatment to ensure we get the cleanest, easiest pool openings in the spring."

Keeping phosphate levels down ensures that algaecide will be more effective through fall and into early spring. Also, when algae are lacking a key nutrient they are less likely to get a serious foothold before the pool is opened.

Staying Flexible

There is a saying, "Blessed are the flexible for they shall not be broken." In today's world pool professionals need to be more flexible than ever when it comes to maintenance. Not only are weather patterns changing, but there are also many new source water challenges (such as lower water tables with more minerals and metal-bound bacteria). This could mean that stain removers, metal sequesterants and clarifiers may be needed when closing and opening pools. Water municipalities now use ammonia-bound chlorination and add phosphates for iron corrosion, so additional oxidation and regular phosphate testing may also need to be incorporated into closing and opening programs.

The challenges of today's water professionals require quick thinking and the ability to adapt to a changing environment. In short, check up on the kids from time to time.

Comments or thoughts on this article? Please e-mail [email protected].

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