How to empty your shell pool?

While an annual renewal of ¼ of your pool water is generally sufficient to maintain healthy and clean water all year round, there are certain special cases in which you will need to drain your pool completely.

For example, if the pool water remains green despite using a suitable treatment, we recommend that you empty your shell pool. The same applies if the shell of your pool is scaled (greyish walls and bottom) or damaged.

However, draining is not without risk for your pool. In fact, if done incorrectly, it can irreversibly damage the structure of your polyester shell pool.

So to avoid any unpleasant surprises, discover in the following lines our advice for emptying the water from your pool safely.

Legislation: can you empty a shell pool?

Before you start draining your pool , it is important to know that the evacuation of water from a private pool is subject to regulations. Indeed, article R1331-2 of the Public Health Code prohibits the introduction of pool drain water into collective sanitation networks (i.e. the sewer system).

Is your pool connected to the collective rainwater network? In this case, you are authorized to drain the water from your pool provided that you have stopped water treatment (chlorine, bromine, etc.) at least 15 days before. Indeed, since rainwater is discharged into nature, it is essential to empty the pool without polluting the environment.

In any case, do not empty the tank without first requesting permission from your local authority. Also remember to find out about the conditions to be respected when emptying (maximum authorized flow rate, etc.) and to warn your neighbors.

Why empty your swimming pool?

When pool maintenance is done properly, it is not necessary to completely renew the water in your pool every year. In fact, using a vacuum cleaner, a pool robot and an efficient filtration system can often keep the water clean and healthy.

Emptying your shell pool to change the water in your pool should only be done every 4 or 5 years, regardless of the type of pool (concrete pool, tubular pool, above-ground pool or in-ground pool).

There are also other reasons why you may need to empty the water from your pool: 

• Pool water that remains green due to the development of algae inside the pool. This phenomenon appears in particular during variations in water temperature or when winterizing the pool , when a step has been carried out incorrectly;
• A pool shell with scale . To get rid of this grayish film that covers the walls and bottom of the pool, you will need to drain and clean it.
• Poor water balance , caused by too high a stabilizer level.
• Wear of the coating or cracks in the hull also require having an empty basin to carry out renovation or repair work.

How to empty your shell pool?

Is your pool green, scaled or damaged? You must therefore empty it. To ensure that this is done without a hitch, it is important not to rush things…

1. Don't drain your pool water in winter

To the question, “should you empty your swimming pool in winter?”, the answer is no!

And the reason for this is simple: in winter, there is a good chance that the ground surrounding your pool will be waterlogged, putting pressure on the shell of your pool. The risk is therefore that the structure will come off its foundation. 

In addition, with temperatures dropping, the risk of frost is greater in winter. This can cause deterioration of the walls, structure or even pipes. It is therefore essential to avoid frost.

To avoid damaging the polyester shell of your pool, we recommend that you empty it as soon as the good weather arrives in the spring. At this time, the ground has already started to dry out; it will then exert less pressure on the shell of your pool.

To enjoy swimming during the summer season, remember to check the weather forecast regularly to find the right time to drain the oil!

2. Stop treating your pool

Spring has arrived and you have decided to empty your pool in the coming days? Also remember to respect the 15-day deadline without pouring chemicals so as not to pollute the soil.

In the meantime, contact your local authority to find out what additional precautions to take and warn your neighbours of any potential ground infiltration .

3. Empty the water from your pool in several batches

To empty the water from your pool, the simplest technique is to drain it using a garden hose . Pumps are also effective for draining it easily. To avoid any risk of flooding and to give the water time to drain, however, be sure to empty the water from your pool in several times.

Once your pool is emptied, make sure to leave at least 20 cm of water inside your pool to prevent the structure from coming off its base. In addition to the water level, installing beams across the width can also be useful to keep the bottom of the pool in place for the entire duration of the draining. However, take care to protect the coating at the contact points, using rags or cardboard sheets.

Finally, don't delay in refilling your pond: the less time it spends without water, the better it will be!