Should I Drain My Pool for the Winter?

When It Makes Sense

• Good fit: You need to carry out structural or surface work that cannot be done with water in place. Tasks such as acid washing, plaster or fiberglass resurfacing, repainting, tile and coping repair, major crack repair, or vinyl-liner replacement are usually safer and more effective when the pool is empty. Scheduling this work during the off-season can reduce summer downtime, but only if the empty shell is protected from groundwater, rain, and temperature swings throughout the winter.
• Good fit: Your pool manufacturer’s written winterizing instructions explicitly recommend draining or lowering the water to a very low level. Some above-ground pools and certain specialty designs have walls, frames, or supports that can be stressed by ice expansion, so the manufacturer may advise a near-complete drain to protect the structure. Always follow the specific guidance for your make and model rather than a generic rule.
• Good fit: You live in a dry climate with well-drained, stable soil and a low water table, and you have a reliable plan to keep the empty basin covered and dry. In these conditions, the risk of groundwater lifting the shell is reduced, and a controlled drain lets you inspect the interior, service lights and fittings, and clean stains thoroughly. Even then, you should monitor the pool and manage any accumulated precipitation.

When You Should Avoid It

• Warning sign: Your inground pool sits in an area with a high water table, clay soil, or heavy winter rainfall. Groundwater exerts hydrostatic pressure against the underside of an empty shell; without the weight of the pool water to counter it, the shell can lift, crack, or bow. This damage can be severe and expensive, which is why full drainage is generally not recommended as a routine winter step for most inground pools.
• Warning sign: You are closing the pool purely out of habit and not for a specific repair or manufacturer requirement. Standard winterization typically lowers the water only below the skimmer and return lines, then blows out and seals the plumbing. Removing all the water eliminates the protective ballast and thermal mass that help the shell resist ground movement and freeze-thaw cycles.
• Warning sign: You cannot reliably prevent rain, snow, or runoff from entering the empty pool. If water pools in the basin and freezes, it can chip tile, crack coping, damage steps, and ruin an unsupported vinyl liner. Keeping an empty pool truly dry requires an effective cover, drainage, and periodic inspection, which adds risk and labor compared with a normal closed pool.
• Warning sign: Your warranty, local code, or community rules restrict drainage or require professional winterization. Draining thousands of gallons may also violate water-use or discharge regulations in some areas. Ignoring these requirements can lead to fines or voided coverage.

Pros and Cons

Pros

• Major maintenance becomes accessible. An empty pool lets you see and treat cracks, stains, scaling, and surface wear, replace a liner, repaint walls, reset tiles, and service drains, lights, and fixtures without working around water.
• There is no standing pool water to freeze inside the shell, skimmers, or returns if the winterization is done correctly. When plumbing is blown out, equipment is drained, and the basin is protected, freeze-related damage to the pool body and piping can be reduced.
• Operating costs during the off-season may fall. An empty pool needs no chlorine, balancing chemicals, filtration, or pump runtime over the winter, which can save money and maintenance time while the pool is not in use.

Cons

• Hydrostatic pressure is the biggest risk for inground pools. Groundwater can push an empty concrete, fiberglass, or vinyl-liner shell upward, causing the floor to pop, walls to crack, or the entire structure to shift. Repairs after such events can be extensive.
• Dry vinyl liners and some surface finishes can shrink, become brittle, crack, or lose adhesion when exposed to cold air and sunlight. A liner that relaxes out of its track may need reinstallation or replacement in spring.
• Draining, refilling, and rebalancing is expensive and time-consuming. It uses a large volume of water, may conflict with drought restrictions or sewer capacity rules, and delays spring opening until chemistry and temperature are restored.

Decision Checklist

• Have I checked my pool manufacturer’s owner’s manual and warranty terms? Many warranties require specific water levels during winter, and improper drainage can void coverage.
• What are my soil type, water table, and typical winter precipitation? Sandy, well-draining soil in a dry region presents a different risk profile than clay or high-groundwater areas. A qualified pool builder or service technician can help assess this.
• Is the drainage tied to a specific repair, resurfacing, or manufacturer directive? If not, a standard winter closure is usually the safer and less expensive option.
• Do I have a plan to keep the empty pool dry and monitored? This means a well-secured cover, a way to remove groundwater such as a sump pump or functioning hydrostatic relief valve, and a schedule to remove rain or snowmelt.
• Are there local rules about discharging pool water? Check for water-use restrictions, storm-drain regulations, or neighborhood covenants before pumping out thousands of gallons.

Alternatives to Consider

For most pools, the preferred winter approach is a standard closure that leaves water in the pool. Lower the water level below the skimmer and return fittings, blow out and plug the plumbing lines, add pool-safe antifreeze where appropriate, drain and store pumps and filters according to manufacturer instructions, and cover the pool with a solid winter cover. This preserves the shell’s ballast against ground pressure and provides thermal mass that moderates temperature swings. For above-ground pools, a partial drain to the level recommended by the manufacturer, combined with an air pillow and a tight cover, is often safer than a full drain. If you must drain for repairs, keep the empty period as short as possible, refill before severe weather arrives when feasible, and consider hiring a professional who can manage groundwater pressure and protect the shell while it is empty.

Final Recommendation

Fully draining a swimming pool for winter is usually not the best default choice. Most inground pools should remain partially filled and properly winterized to protect against hydrostatic pressure, surface damage, and liner shrinkage. Reserve complete drainage for situations where the manufacturer or a qualified pool professional recommends it, or when the pool must be empty for repairs, resurfacing, or liner replacement. If you do drain, install safeguards such as a reliable cover, a sump pump or hydrostatic valve management, and regular inspections for precipitation accumulation. Because pool structure and safety decisions involve high stakes and local conditions vary widely, consult a licensed pool service professional before deciding to drain your pool for the winter.