Is Pool Maintenance Necessary in Winter?

Yes, winter pool maintenance is required regardless of location, pool type, or surface material. Neglecting it can lead to equipment damage, chemical imbalance, algae growth, and costly repairs. Proper winter care ensures a clean and functional pool at spring opening and extends system lifespan. Maintenance varies by climate zone, pool type (above-ground or in-ground), and cladding (plaster, tile, PVC membrane (for example, 60 mil pool liner), fiberglass).

Zone	Example Regions	Winter Lows	Core Tasks
Warm (USDA 9–11)	Florida, Southern California, Arizona	Rarely below 20°F	Keep the pool open or lightly covered. Run pump 2–4 hrs weekly. Test and balance water monthly.
Mild (USDA 7–8)	Carolinas, Pacific Northwest, Texas	10–20°F	Partial winterization. Cover pool. Check water every 2 weeks. Drain lines if freezing forecast.
Transitional (USDA 5–6	Midwest, Virginia, Colorado	0–10°F	Full winterization. Blow out lines, add antifreeze. Check cover monthly for snow/ice.
Cold  (USDA 3–4)	Northeast, Minnesota, North Dakota	Below  0°F	Complete shutdown. Drain equipment. Use air pillows. Inspect cover every 2–3 weeks.

Feature	Above-Ground	In-Ground
Drain Level in Cold Climate	Below return jets	12–18 inches below skimmer
Cover	Reinforced tarp + air pillow	Safety mesh or solid cover with water bags
Freeze Risk	High	Low, but plumbing vulnerable
Snow Load	Remove snow promptly	Use cover rated for 500+ lbs/sq ft

1. Water Chemistry: Calcium 200–275 ppm, alkalinity 100–150 ppm, pH 7.2–7.6.  
2. Drain: 12–18 inches below skimmer (in-ground pool).  
3. Risk: Etching if calcium drops; scaling if too high.  
4. Action: Increase calcium before closing. Use winter algaecide.

• Water Chemistry: Calcium <250 ppm, chlorine 1–3 ppm.
• Drain: 12–18 inches below skimmer.
• Risk: Tile pop-off from ice expansion.
• Action: Use expansion pillows.

• Water Chemistry: Alkalinity 80–120 ppm, pH 7.2–7.6.  
• Drain: Keep full (in-ground); 4–6 inches below skimmer (above-ground).  
• Risk: Fading if chlorine >5 ppm long-term. 
• Action: Use enzyme cleaner.

• Water Chemistry: Calcium <150 ppm, pH 7.2–7.4.  
• Drain: Never below skimmer (risk of shell pop-up from groundwater in spring).
• Risk: Structural damage if drained in frozen ground.  
• Action: Maintain high water level. Blow out and cap lines.

1. Clean thoroughly – brush, vacuum, skim. 
2. Balance water – test pH, alkalinity, calcium, chlorine. 
3. Shock pool – raise chlorine to 10 ppm. 
4. Add winter algaecide and stain preventer. 
5. Drain equipment – pump, filter, heater, chlorinator. 
6. Blow out lines – use shop vac or compressor (60 PSI max.) 
7. Add pool-grade antifreeze to plumbing (non-toxic, -50°F rated). 
8. Install cover – secure tightly, remove standing water/snow. 
9. Monthly checks – inspect cover, water level, chemistry (if open).

• Warm climate: Operate normally or reduce filtration. Full winterization is not required.  
• Cold climate: Complete shutdown required. Freeze protection is a priority.  
• Above-ground pools: More vulnerable to wind and collapse. Use extra tie-downs.  
• In-ground pools: Focus on plumbing and water balance.  
• Thick PVC membrane and fiberglass: Minimal winter maintenance due to non-porous surfaces.  
• Plaster and tile: Require strict water chemistry to prevent surface damage.

• DIY: $100–$300 (chemicals, antifreeze, cover care)  
• Professional Closing: $250–$600 (includes blow-out, chemicals, inspection)  
• Recommended: Hire pros in cold climates or for complex systems.