Swimming Pool Blog

Can I Keep my Pool Uncovered all Winter?

Can I Keep my Pool Uncovered all Winter?
Rob Cox  October 13, 2016

Back when I ran all over Northern Virginia on a pool service route, we had a customer with a cute backyard pool, very colorful and charming, like the homeowner, a single woman in her late 50's.

She couldn't stand to look at a solid pool cover all winter, and the idea of a safety cover was also not appealing. She asked me if I could winterize the pool, but not put a cover on the pool.

I took a look around. The pool backed to a golf course, and there were no large trees around the pool, just a few small maple trees, and the sun exposure to the pool was about average.She had a solid fence and no children in the house, so safety was not a main concern.

"We can winterize it, and Not cover the pool, if that's what you want", I told her, "But..., you'll need to keep the pool clean, with a Leaf Rake or a Leaf Master. Leaves use up the algaecide, and can leave stains. And, you should brush the pool weekly. And, also test the water at least monthly, And your going to need more chemicals to keep the water clear...".

She stopped me by raising her hand, and with my mouth still hanging open, said "How much would it cost for you to take care of all that for me?". :-)

She kept the pool mostly clean, and we stopped by once per month to clean the pool and balance the water. During the coldest winter months, when the pool was frozen solid, we didn't need to visit.

Must You Use a Winter Pool Cover? 

It is recommended to use a winter cover, and 99% of pool owners who have their pool winterized will cover the pool for winter. However, if you are in that 1% that wants to close the pool, but keep it uncovered all winter, here are the steps we took to do it for our customer above.

  1. KEEP THE POOL CLEAN:  If your pool is surrounded by trees, stop reading and buy a pool cover. But if you have low leaf litter, or a desert environment perhaps, read on. With the pumps and pipes winterized, you can't vacuum the pool through the system. The options are to use a Leaf Master® type device, which connects to a garden hose to create a venturi vacuum. You can also use a pool leaf rake, the bag type of skimmer net, to scoop leaves, twigs, bugs from the surface, and when you become proficient, from the floor easily. A good pool brush should also be used vigorously each week, to give some water circulation, and to break up any tiny bacteria or algae colonies that are forming on the wall or floor surfaces.

  2. TEST & BALANCE THE WATER: Use a good test kit, or test strips to run the full battery of tests on the pool water, once or even twice per month. Winter rain and snow, and everything floating in the air above is absorbed into your pool during winter, and this can consume your winter pool chemicals, and pummel your pH, Alkalinity and Calcium Hardness levels. In addition, be sure that your cyanuric acid level is at 50 ppm, to protect your chlorine from the sun. To add chemicals to an uncovered pool during winter, predissolve by adding to a bucket filled with water, then pour around the edge. Then brush the pool well to disperse the adjustment chemical.

  3. CHLORINE + ALGAECIDE: Keep your chlorine level up in the pool by filling a chlorine floater (or two), with tablets and floating them in the pool. Refill the floaters as needed, and test the water regularly to be sure that you have at least 1.0 ppm, until water temperatures drop below 60 degrees, then it can go to 0.5 ppm. For winter algaecide, add an initial dose of 1 qt per 10000 gallons, and a weekly maintenance dose of a good winter pool algaecide like 60 Plus, If you notice algae growing in early fall or late spring, shock the pool with a heavy dose of your favorite pool shock, and brush well. When the pool is frozen solid, or has water temperatures in the 40's - you can suspend treatment.

  4. OPEN THE POOL EARLY: Oh, I didn't mention this part before sorry. My customer who wanted to leave the pool uncovered in winter also was agreeable to opening the pool in April, which is about a month earlier than most people in the Mid-Atlantic region. She also closed the pool later than usual too, in late October. When the water temperature rises, and sunny days grow longer, it can be hard to control algae growth without the pool filter. So plan on opening the pool about a month before normal, or when the water temperature rises into the 60's. While the water is still cold, you can run the pool pump less, say 6 hours per day, and maintain clear water, in most cases.


- Rob