Should You Leave Water In The Swimming Pool During Winter?

Large swimming pool closed for winter

After a summer of sun and fun, you may wonder what you need to do to set up your swimming pool for the winter months.

The most common question we get is, “Should I leave water in the pool during the winter?” The answer is a resounding “YES!”

Why? Many pools rely on the water pressure to retain the integrity of the structure and keep the liner in place. Some require the weight of the water to maintain hydrostatic balance to stay within the ground. Regardless, leaving your pool empty during the winter months can lead to significant damages.

So what should you do to prepare your pool for winter? Here are 3 ways to prepare your pool for winter now:

Drain some, but not all of the water

The rule of thumb is to drain your pool’s water BELOW the skimmer line during the winter. Different types of swimming pools require different minimum water levels. For example:

  • An aboveground pool that relies on the water pressure to support the structure and keep the liner in place should not be drained. Remove just enough water so there’s room for the water to expand and contract as the temperature fluctuates.
  • An inground vinyl pool needs 6 to 12 inches of water covering the shallow end at all times.
  • A concrete or fiberglass pool often relies on the weight of the water to remain hydrostatically balanced so it stays in the ground. A drained pool, combined with the wrong set of circumstances, could result in a concrete pool being lifted off the ground or a fiberglass pool breaking completely.

Keep it clean

Adding the right winterizing chemicals to the water, like chlorine stock, stain prevention and algaecide, help to prevent the water from freezing. These winterizing chemicals also maintain the right chemical balance so that the water stays clean and safe.

Maintaining clean and chemically balanced water in the pool will help protect the pool liner while making it easier and faster to reopen the pool next spring.

Cover it up

A pool cover is essential for ensuring safety, keeping the water clean, and protecting the pool from the elements.

Enough water should be drained to allow the cover to be installed properly. Ensure that the cover is stretched taut over the pool. This will help prevent the cover from collecting large amounts of water and debris, which can cause stress, rips and other damage.