How to Winterize Your Swimming Pool

How to Winterize Your Swimming Pool


It’s officially fall and as winter draws near, it is once again time for homeowners to winterize their swimming pools.  Winterizing a swimming pool not only can protect it from damage caused by frozen water, the pool owner can simplify the process for preparing it for use again in the spring. Though the procedures for winterizing an above ground pool and an in-ground pool differ slightly, most of the steps are exactly the same.

Follow the steps below to prepare your in-ground or above ground pool for the winter season.

  1. Balance water chemistry. Start with a clean slate. Make sure your pH, Total Alkalinity and Calcium Hardness are all within balance. By balancing water chemistry, the surface of the pool will be protected from staining and etching.
  2. Winterize the water. Add a winterizing chemical kit to the water to help keep it clear for the next season. Follow the directions for the kit provided by the manufacturer. Be careful with any products that have chlorine or bromide, as they both have the potential to stain the inside of the swimming pool if not used properly.
  3. Lower the water levels. Lower the water level in the above-ground or in-ground swimming pool to below the mouth of the skimmer. Ensure that no water is trapped inside the skimmer, as when it freezes and expands it could break the equipment. Drain all water from the filter and pump as well. Turn the pump on for a moment to get the water out of the veins, but only briefly as the seal can easily be burned out in no time. Do not re-plug drains, so any precipitation that may accumulate has the potential to freeze and damage equipment over the winter.
  4. Purge the plumbing. Disconnect all of the hoses and blow out the water from all plumbing lines of the filter system and skimmer. This can be easily accomplished using a shop vac or air compressor. After purging the veins, add a plug in the line at the wall outlets. Though rubber plugs work well, threaded winterizing plugs provide the ultimate protection from unwanted water.  Be sure to open the air relief valve on top of the filter if you have one.
  5. Clean and maintain. Use a brush on the walls and floors of the in-ground or above-ground swimming pool. Remove any leaves, silt or algae. Vacuum the filter out with the shop vac. Perform any recommended routine pump maintenance following your manufacturer’s manual for instructions and schedule. Ensure all feeders are empty of chemicals, as leaving them in your feeder over the winter can cause damage. Whenever possible, bring any detachable pool equipment like pressure gages, filters or pumps indoors for the winter. Remove ladders for above-ground pools.
  6. Secure the cover. Covering the pool keeps debris, sunlight and precipitation out of the pool, while further reducing the potential for algae growth. A high-quality mesh safety cover is ideal for winterizing an in-ground pool. A sturdy cover and air pillows are a perfect combination for keeping above-ground pools secured. The air pillows cause the cover to arch in a dome-like shape to prevent pooling and debris accumulation.

When winter approaches, temperatures drop and the swimming pool falls into disuse, it is best to take precautions to safeguard your investment, no matter where you live. The temperature can drop below freezing nearly anywhere during the cold season. When water freezes, it expands, which can cause great damage to a pool, pool plumbing and other equipment like filters and pumps. In addition to protecting these items, all of the detail work performed in the fall will make restarting the pool in the spring much easier. By following these steps, you can ensure that your swimming pool weathers the winter well to provide family fun for many summer seasons to come.