Keeping an above-ground pool in good condition year-round requires a bit of foresight, especially as winter approaches. One of the most common questions pool owners ask is: Are you supposed to drain an above-ground pool for winter? The short answer is no—not entirely. Draining it completely can actually cause more harm than good. But there’s a lot more to winterizing your above-ground pool than just leaving the water in. This guide provides a detailed, season-by-season roadmap for preparing your above-ground pool for winter and explains why completely draining it is generally discouraged.
Understanding Why You Shouldn’t Fully Drain an Above-Ground Pool for Winter
Above-ground pools are made of flexible materials—typically steel, aluminum, or resin wall panels with a vinyl liner. These materials are sensitive to environmental factors, and completely draining the pool during the winter months can lead to serious damage.
Structural Integrity and Liner Damage
When water is removed from an above-ground pool, the structure is no longer held in place by the hydrostatic pressure of the water. Without proper bracing, this can lead to structural warping, collapsing, or tearing of the vinyl liner. In wet or freezing climates, residual moisture trapped in seams can freeze, leading to expansion and tearing.
Groundwater and the Risk of Liner Floatation
In areas with high water tables, draining the pool can actually allow groundwater infiltration, potentially causing the liner to float or buckle. If the groundwater enters behind the liner while the pool is empty, the pressure can lift the liner off the wall brackets or distort it entirely when the soil thaws in spring.
Chemical Imbalance and Algae Growth
An empty or partially emptied pool is prone to algae growth when exposed to damp conditions. Without water circulation, algae can thrive on standing moisture, dirt, and sunlight. Cleaning a neglected, drained pool in the spring can be a time-consuming and intensive job—costing more effort than properly winterizing a full pool.
What is the Correct Way to Winterize an Above-Ground Pool?
The key to a well-maintained pool during winter is not to remove the water but to prepare the pool and its components to endure the colder weather safely.
Step 1: Clean the Pool Thoroughly
Start by vacuuming the floor and removing all debris from the pool. Brush the walls and skimmer area to dislodge any algae or buildup. Use a pool net to scoop up leaves and dirt floating on the surface.
Step 2: Balance the Water Chemistry
Balancing the pH, alkalinity, and calcium hardness is crucial for winter protection. Imbalanced water can corrode metal parts and stain the pool surface. Ideal levels include:
- pH: 7.2–7.8
- Total Alkalinity: 80–120 ppm
- Calcium Hardness: 200–400 ppm
Once the water is balanced, perform a chlorine shock treatment to ensure all bacteria and algae are eliminated before winter begins.
Step 3: Lower the Water Level (But Not All the Way)
Drain the pool water to a level that’s below the skimmer but above the top of the pool wall. This prevents freezing water from expanding into plumbing lines and keeps the structure pressurized enough to maintain integrity. Typically, this means lowering the water about 4–6 inches below the skimmer mouth.
Step 4: Winterize the Pump, Filter, and Pipes
Turn off the pool pump and power supply. Remove drain plugs and drain all equipment water. Use a pump to clear water from the plumbing lines. Add pool-specific non-toxic antifreeze into the lines to prevent freezing.
Step 5: Install a Quality Winter Cover
Use a strong, UV-resistant solid winter cover that fits your pool securely. Reinforce it with water bags or straps if necessary. A proper cover keeps out debris, sunlight (which promotes algae growth), and helps prevent accidental drowning by maintaining a tight fit.
Step 6: Optional – Use Winterizing Chemicals
Adding a winterizing chemical kit or algaecide ensures that algae doesn’t develop during the off-season. Some kits also contain stain inhibitors that protect the pool surface.
Step 7: Store Accessories Properly
Remove ladders, diving boards, pool toys, and vacuum heads. Clean them and store them in a dry, indoor location to protect against corrosion and cracking. If the weather is extremely cold, store hoses and any winterized equipment inside a basement or shed.
When Is Draining an Above-Ground Pool Necessary or Acceptable?
While most above-ground pools shouldn’t be fully drained for winter, there are exceptions. Certain situations may necessitate complete or partial draining for winter maintenance.
Structural Repairs or Liner Replacement
If you plan to repair or replace the pool wall, floor, or vinyl liner, you’ll need to drain the pool. However, this should ideally be done when no freezing is expected, and only for a short duration. Water should not be left out long enough for frost or ground moisture to reach the pool base.
Poor Drainage Around the Pool Area
In regions where seasonal snowmelt or heavy rains cause standing water around the pool, some pool owners choose to lower the water level below the skimmer but leave enough to maintain hydrostatic pressure. Draining the pool too much could invite groundwater damage, but partial draining may help with overflow management.
Removing the Pool for Winter Storage
For temporary above-ground pools (like inflatable or small frame pools), some owners choose to completely drain the pool and store it indoors for winter. This is only acceptable when the design allows disassembly and reinstallation without damage.
Suitable Scenarios for Complete Drainage
| Scenario | Drain Completely? | Notes |
|---|---|---|
| Replacing a vinyl liner | Yes | Only if done before freezing and in dry conditions |
| Major structural repairs | Yes | Winter is not ideal—reassembly must wait for favorable conditions |
| Portable or inflatable pool | Yes | Requires proper storage and reinstallation in spring |
| Heavy snowfall / flooding risk | No | Water should remain to protect structure |
The Dangers of Improper Pool Winterization
Even with careful planning, mistakes in winterizing can lead to costly damage. Understanding these risks helps pool owners make better decisions.
Cracked or Warped Wall Panels
Metal and resin wall panels may buckle when the surrounding pressure is off-balance. Fully draining the water removes the tension that keeps these panels aligned, and freezing temperatures can amplify warping if moisture gets into corners or seams.
Vinyl Liner Damage
Vinyl liners can tear from exposure to cold, heat, or sharp debris when the pool is empty. They also dry out quickly, becoming brittle and prone to cracking. If the liner dries too much, it’s nearly impossible to re-stretch during reinstallation.
Plumbing and Equipment Damage
If water isn’t fully removed from pipes, filters, pumps, or heaters, it can freeze and expand, causing cracks. This can lead to expensive replacements and delays in reopening the pool in spring.
Pest Infestation
An improperly drained or covered pool can become a hotbed for mosquitoes or attract small animals seeking shelter. This increases the chance of disease, contamination, and debris problems.
Top Tips for Choosing and Using Winter Covers
A good cover is the last and most important line of defense against weather damage. However, not all covers are equal.
Choosing the Right Winter Cover
- Solid covers are best for winter as they block sunlight and debris.
- Mesh covers allow water to drain but are not ideal for debris-heavy areas.
- Ensure that the cover is the right size and shape for your above-ground pool.
- Look for UV-treated or reinforced covers for long-term durability.
Securing the Cover
- Use water bags, cover anchors, or straps to keep it anchored tightly.
- Avoid leaving gaps around the edge of the cover where animals or rainwater might enter.
- Consider a cover pump to remove standing rainwater or melting snow.
Removing the Cover in Spring
Before reopening the pool, remove accumulated snow and debris. Use a leaf net or manual lifting to unroll the cover without tearing it. Rinse and dry the cover before storing it away for reuse next year.
Conclusion: Maintain the Water, Protect Your Investment
So, are you supposed to drain an above-ground pool for winter? The answer is clear: no, not completely. The water serves a crucial structural purpose, maintaining hydrostatic balance and protecting the walls and liner from damage. Draining the pool unnecessarily can lead to warping, collapse, and expensive repairs. Proper winterization, instead, involves chemical balancing, lowering the water level appropriately, using a high-quality winter cover, and protecting the equipment from freezing.
By following the steps outlined in this guide, pool owners can ensure their above-ground pools remain safe and functional throughout the winter, and ready for enjoying when summer rolls back around. Whether you live in a snowy northern state or a temperate southern region, always prioritize structure, chemical safety, and equipment care during the winterization process. With proper planning, your pool will outlast the seasons and continue to provide years of enjoyment.
About the Author
This guide was crafted by expert pool care professionals with over a decade of combined experience in both residential and commercial swimming pool maintenance. Our goal is to empower pool owners with practical, science-based advice that helps them protect their investments and improve their pool care outcomes.
Do you have to drain an above-ground pool for winter?
Draining an above-ground pool completely for winter is generally not recommended. Most above-ground pools are designed to stay partially or fully filled during the off-season to help maintain the structure’s integrity. Completely emptying the pool can lead to the walls collapsing or the liner shrinking and becoming damaged due to exposure to cold temperatures and wind.
However, the correct approach involves partially lowering the water level, typically below the skimmer and return jets, to prevent freeze damage. It’s important to use a pool cover and winterizing chemicals to protect the water quality. Always check the manufacturer’s guidelines and consult a pool professional familiar with your specific model before deciding how much water to keep or drain.
Why is it bad to completely drain an above-ground pool in the winter?
Draining an above-ground pool completely during winter can cause structural damage because the water usually helps support the sides of the pool. Without water pressure against the walls, the pool may collapse or warp, especially when exposed to wind or heavy snow loads. Additionally, an empty pool is more vulnerable to debris accumulation and liner damage, which could lead to costly repairs or replacements.
Moreover, the water in the pool acts as a barrier against air and temperature fluctuations. If drained, pool components such as the liner, skimmer, and plumbing are more susceptible to cracking due to freezing and thawing cycles. Draining also exposes the pool to sunlight, which can degrade the vinyl liner over time, especially when the water isn’t there to provide a protective barrier.
How much water should I drain from my above-ground pool for winter?
The proper way to winterize an above-ground pool is to lower the water level to just below the skimmer and jets, typically about 6 inches below the skimmer mouth. This prevents water from freezing in those components and causing cracks or other types of damage. However, the exact depth may vary depending on your pool design, so it’s best to follow the manufacturer’s instructions for best results.
It’s also important to use a submersible pump for complete control and accuracy when lowering the water. You should leave enough water in the pool to protect the liner and maintain structural support. If you have a mesh cover, you don’t need to lower the water as much as with a solid cover, which collects water and snow that must be drained away from the pool surface.
Do I need to remove the ladder and other accessories before winter?
Yes, removing the ladder, diving board, and other accessories is generally advisable before winterizing an above-ground pool. These items can be damaged by heavy snow, freezing temperatures, or prolonged exposure to pool chemicals. Removing them also makes it easier to clean and cover the pool properly, reducing the risk of staining or wear on both the equipment and the pool surface.
All accessories should be cleaned, inspected for damage, and stored in a dry, frost-free location for the winter. Ladders and rails should be checked for rust or corrosion, and lightly lubricated if necessary. Taking these steps helps prolong the life of your pool equipment and makes setup easier when the next swimming season begins.
What should I do with the pool water after winterizing?
After winterizing, the pool water should be treated with proper winterizing chemicals, including algaecide and a chlorine tablet or other sanitizer, to prevent algae growth and bacterial contamination during the off-season. A quality pool cover—either solid or mesh—should then be securely fastened over the pool to keep debris and leaves out and to protect the water from exposure to contaminants.
Throughout the winter, it’s still important to monitor the water occasionally, especially after heavy storms or in warmer spells when algae can develop. If using a solid cover, use a cover pump to remove accumulated rain or melted snow to avoid putting stress on the cover and adding undue pressure on the winterized water level. Keeping the pool water balanced and protected ensures a smoother opening in the spring.
Can I leave my above-ground pool pump and filter outside for winter?
Leaving pool pumps and filters outside during winter is not recommended, especially in areas with freezing temperatures. The water inside the equipment can freeze and expand, leading to cracks in the pump housing, filter tank, or plumbing connections. To avoid damage, these components should be cleaned, drained, and stored in a dry, frost-free location like a basement or garage.
Before storage, it’s important to winterize the pump, filter, and heater by removing water and using non-toxic antifreeze in the lines, if necessary. Components like the pressure gauge, filter valves, and pump lid should also be checked for wear and cleaned to prevent rust or mold formation. Proper care and storage will extend the life of your equipment and ensure trouble-free operation come spring.
How do I properly cover and secure my above-ground pool for winter?
Choosing the right cover is essential for winter pool protection. Solid vinyl covers block debris and most sunlight, minimizing algae growth, while mesh covers allow water to drain through and are good for heavy snow and rain areas. The selected cover should fit snugly over the pool and be secured with a cable and winch system or specially designed cover clips to prevent sagging, tearing, or wind uplift.
Before covering, clean the pool thoroughly and balance the water chemistry. Install a winterizing kit that includes air bags or pillows to absorb the pressure of ice expansion. Use water bags or concrete blocks on the cover to hold it down safely without puncturing it. Always check the cover at least once a month during winter to ensure it remains secure and is not holding excess water or debris.