How to close your pool for the winter

Winterizing a pool sounds easy enough. Drain the water and you’re done closing the pool for winter, right? Wrong. There’s a series of steps necessary to prevent the freeze and thaw damage that can create cracks or leaks in the pool, equipment, and water lines. If a mistake is made in closing your in-ground or above-ground pool, you’ll be in for expensive repairs when you open the pool in spring.

If you’re in doubt about closing your pool correctly, consider hiring a pro and avoid these mistakes pool owners often make when winterizing a pool.

Photo Credit: iStock.com/ Parilov

Although the steps are usually straightforward, the most common mistake DIYers make when closing a pool is having unbalanced water chemistry. This can allow scale to accumulate or corrode the pool.

Ensuring winterizing chemicals are adequately dissolved is often overlooked. These chemicals can stain or damage the pool. Many pool owners add a chlorine shock for winterization, which can weaken the pool lining and throw the winterizing chemicals off balance. Ensure you use a chlorine-free shock.

Without the right method and product, cleaning the pool filter can cause irreparable damage. Extend the life of your pool filter by carefully following the manufacturer’s cleaning instructions.

Not protecting the pool heater is another step that’s often forgotten. In harsh climates, it’s best to use a pool heater cover to protect it from moisture and animals.

1. Perform a thorough inspection of pool equipment and structure to identify any needed maintenance or repairs.
2. Clean and test water to ensure it’s balanced, and remove all dirt and leaves which can stain if left in the pool all winter.
3. Clean pool filter and drain pool water to below skimmer level, ensuring compliance with local pool water discharge restrictions.
4. Use an air blower to remove all water from plumbing lines and add anti-freeze to lines for extra protection.
5. Remove and store accessories such as lighting, skimmer basket, and saltwater equipment (if applicable).
6. Add appropriate winter chemicals for your size and type of pool.
7. Install the winter pool cover to prevent debris, animals, or people from falling into your pool.

The basic steps are the same for winterizing all pools, but there are a few unique considerations for an above-ground pool. Above-ground pools have more equipment that needs to be removed, cleaned, and stored for winter such as the stairs, lights, chlorinator, and pump. Also, the pool deck will need to be pulled several inches away from the pool to prevent damage to the pool structure. Finally, it’s important to remove snow buildup over 12 inches to relieve excessive pressure on the above-ground pool walls.

Later is always better, when it comes to pool closing. The warmer the water, the faster it will turn into an algae-filled mess. Waiting until the water temperature is constantly less than 18 degrees Celsius (but before the first frost) will help ensure you will have a clear pool in the spring. And don’t end your pool maintenance just because the swimming season is over. Be sure to maintain chlorine levels and keep your pool pump running 10-12 hours per day until the pool is closed.

It’s important to remember to check the water level of your pool periodically over winter to determine if there are any leaks. If you discover your pool is losing water, keep adding water to the desired level until the leak can be repaired once the pool is opened in spring.