How to Winterize a Pool the Right Way

Winter is creeping in, and if you own a pool, it’s time to start prepping for the off-season. Winterizing your pool the right way helps protect your equipment, keep the water clean, and make spring opening easier. Whether you’re a new pool owner or need a refresher, this guide will walk you through each step.

Why Winterizing Matters

Skipping winter prep can cause serious issues like frozen pipes, cracked equipment, or algae blooms. Plus, if you winterize properly, you’ll spend less time and money fixing your pool when the warm weather returns.

When to Start Winterizing

The best time to winterize your pool is when the water consistently stays below 65°F. If you close it too early, you risk algae growth. Wait too long, and you could be dealing with frozen lines.

What You'll Need

Before getting started, gather these essentials:

• Pool test kit

• Pool shock and algaecide

• Winterizing chemicals

• Skimmer plugs or gizmos

• Winter pool cover

• Air compressor or shop vac

• Pool brush and vacuum

• Cover pump

Step-by-Step: How to Winterize a Pool

1. Clean the Pool Thoroughly

Brush the walls, vacuum the floor, and remove any leaves or debris. A clean pool is less likely to develop staining or algae.

2. Balance the Water Chemistry

Test and adjust these levels:

• pH: 7.4 to 7.6

• Alkalinity: 80 to 120 ppm

• Calcium hardness: 200 to 400 ppm

Use winterizing chemicals or shock to sanitize the water.

3. Lower the Water Level

Drain the pool water to below the skimmer opening, but make sure not to go too low. If you have a vinyl liner, avoid draining too much to prevent liner damage.

4. Add Algaecide and Winter Chemicals

Pour in an algaecide to prevent blooms. Add any specialized winterizing chemicals recommended for your pool type.

5. Blow Out the Lines

Using a shop vac or air compressor, blow out the water from your return lines, skimmer, and main drain. Plug the lines with winter plugs or gizmos to prevent water from reentering.

6. Remove and Store Equipment

Take out ladders, diving boards, skimmer baskets, and return fittings. Clean them and store them in a dry place.

7. Cover the Pool Securely

Lay the winter cover over the pool and secure it tightly. Use water bags or cover clips if needed. Make sure there are no gaps for debris to get through.

8. Add a Cover Pump

Place a cover pump on top to remove rainwater or melted snow. Standing water can damage the cover and add unwanted weight.

Common Mistakes to Avoid

• Closing too early while the water is still warm

• Forgetting to balance chemicals

• Leaving water in the pipes

• Using a worn-out or poorly fitting cover

How to Maintain Your Pool During Winter

Even when your pool is closed, keep an eye on it:

• Clear off leaves and snow from the cover

• Check for any sagging or wear

• Use a cover pump to remove standing water

• Do a mid-winter chemical check if temperatures fluctuate

When to Reopen in Spring

Once temperatures stay above 65°F consistently, you’re in the clear to start opening your pool again. Starting too early can waste chemicals, and waiting too long could allow algae to take hold.