In summer, a pool is a perfect retreat. When the blazing hot sun gets too much, those crystal clear waters draw you in.
For kids, a pool in summer is an opportunity to play without overheating. Adults appreciate the calming relaxation of gently lapping water.
But in winter, the pool is a different story. As days get dark, and the wind turns bitter, no one wants to think about diving into a freezing pool. But it’s a bad idea to just leave it be. You need to winterize your pool.
Winterizing is a way of making your pool safe over the colder months. It’s necessary to protect the pool, and to make things easier for you when the summer months roll in.
This guide can help you get your pool ready to ride out the winter, ready for the next glimpse of sunshine.
How to winterize a pool
Clean the pool. You absolutely have to clean the pool before winter. If you don’t do this, you’ll be in for a horrible shock when the summer comes around. Use a pool vacuum to clean any grit up from the bottom, and a skimmer to remove anything that’s floating on the top. Scrub down the floor, and brush all the sides well. When you put the cover on, it needs to be over a completely clean pool.
Remove and clean all pool accessories. Pool toys, railings, wall fittings, brushes, skim baskets etc. They all need to be removed, scrubbed until they’re spotless, and sanitized. Leave them to dry completely. Otherwise, you risk growing algae and bacteria over winter.
Balance the water. The water is what keeps your pool healthy, so you need to be aware of the chemistry of it. Any problems now can only be made worse over the winter, so before you put your pool away, the water needs to be just right.
To balance your water, you should get a water testing kit. The best ones come with testing strips, which allow you to really easily check different chemical levels in the water.
When testing the pool, check to see that the alkalinity is between 100 and 150 parts per million (ppm), the pH level is 7.2 to 7.6, the calcium hardness is between 175 and 225 ppm, and the chlorine level is 1 to 3 ppm.
Start by adjusting the alkalinity, and then carefully work on everything else. It’s better to be on the higher side of average. Over winter, the levels will naturally start to come down.
Shock. Shock is adding a huge amount of chlorine to your pool in one go. This effectively kills the remaining bacteria and algae. You may have done it in the summer after a particularly busy day, but it’s worth doing before packing up for winter as well.
Shocks can take a while to get to work, so it's best to get on with this a couple of days before you plan on putting your winter cover on.
Add winterizing algaecide. A winterizing algaecide is just a little extra help to stop algae from developing over winter. It isn’t necessary, but it can be helpful. If you’re used to seeing a green pool, then an algaecide can help prevent build up.
Lower the water levels. The water needs to be carefully lowered, until it’s roughly 4 to 6 inches below the bottom of the skimmer. There are a few reasons for doing this. It helps to clear the rest of the water out of the plumbing, so it doesn’t freeze. A lower level is also needed if you suspect the water might freeze over winter. If you live in an area with heavy rain, lowering the water can prevent the pool from overflowing if there’s excessive rainfall.
Drain and clean the filter. How you approach this will depend on what style of filter you have. If you have a sand or Diatomaceous Earth (DE) filter, they need to be drained and backwashed, and then stored indoors. If a sand filter is too heavy to carry indoors, remove the drain plugs and leave outside. For a cartridge filter, drain it and rinse it, and then keep inside.
Remove all drain plugs and filters, and leave them to drain. Store them together, and store them inside if you can.
Cover your pool. When the pool is scrubbed clean all over, it’s finally time to put the cover on. A winter cover offers good protection against anything that might fall into your pool, and the dark it provides inhibits the growth of algae and bacteria. Secure it tight using winter cover clips or a cable and winch. It needs to be tight, to stop anything from sneaking in.
Keep an eye on it. If you live in a place where the temperature regularly drops close to freezing, then you want to keep an eye on how your pool is doing. Similarly, if there are heavy winds or rain, take a moment to check everything is okay.
Why winterize your pool?
Okay, there are a lot of steps to winterizing your pool, and it isn't the easiest of activities. However, the work you need to do winterizing is nothing compared with what you’d find in summer if you didn’t.
Winterizing is important because it keeps your pool safe. The cold temperatures can freeze the pumps, filters, and even crack the tiling.
Winterizing dries out the parts liable to freeze and break.
Without use and care, algae and bacteria can thrive. Left alone over winter, you’ll likely find the water in summer needs a lot of work to be clean again.
After winterizing, you still need to clean and balance your pool before use, but it’s a much easier task.
Of course, if you live in a place with balmy weather year round, there’s no need to winterize your pool. As long as you keep it clean, your pool can offer you the perfect refuge, even as the sun blazes on.