How to wake up your swimming pool when temperatures get warmer

Preparing your pool for summer is a job with the promise of happy days ahead, but there are certain steps which need to be taken.

Before you do anything, however, check the drought restrictions in your area, to see if you are allowed to fill swimming pools.

You can do this using the 'Vigieau' website, which gives a commune by commune overview of drought restrictions.

Read more: What is France's 'drought' website VigiEau?

France is divided into two regions – those where winter pool water falls below 12C and those where it remains above.

Where water temperature falls below 12C, swimming pools are usually “put to sleep” in the winter with all the electric equipment switched off. In places where it is above 12C, this does not always happen.

The low temperature means that the risk of algae, bacteria or other nasties multiplying is low, and it is safe to leave the pool without the water filtered, after a good winter clean, and a check that the pH of the water is between 7 and 7.4.

Removable parts like skimmer baskets are taken out, the water level is lowered by 10 cm, winter corks are put into outlets, a wintering anti-fungicide and anti-chalk product is added to the water, and finally, the cover is pulled over.

An additional check is needed to make sure that all the pipes in the pump house which might freeze are well insulated and clean the pumps to make sure calcium deposits do not cause any blockage problems.

For areas where the water is likely to be above 12C, the water continues to be filtered using a less intensive winter programme.

But pools in the area also require a good clean and water treatment, before the cover is put over the pool.

Read more: Stop stigmatising us during droughts, say pool owners in France

The key temperature is 12C

To open up the pool for the new season, the key temperature again is 12C – you have to wait until the water is above this temperature.

Where the pump has been off all winter the restart process is a bit longer, than when it has been left on.

The first step is to work on the pool and its surroundings.

Take off the winter cover, and any floats, or winter corks in outlets which you might have fitted.

Clean them, fold them carefully, and stock them in a dark space, ready for the end of the season.

Put back the skimmer baskets, take out the corks from outlets and make sure everything is in place.

Some people take photographs each autumn as a memory jogger, so they do not forget anything.

The next step is to clean the edge of the pool using a hose jet or a power washer, being careful to direct the stream away from the poolside.

Next, use a net to clean as many of the solids as you can from the pool.

Then it is time to clean off the watermark left by the winter water level, using an appropriate product and lots of elbow grease.

Once this is done top up the pool so it reaches a third of the way up the skimmers.

The next step is to get the pump house working, before treating the water.

First check there has been no damage from frost or animals nesting, before cleaning the filter, and turning on the pump.

Sometimes you need to use a screwdriver to turn the pump when it has stuck.

Set the filter programmer, and if you have a water heater, robot cleaner or equipment like a swimming current, turn them on to make sure they are working properly.

Check that the water is warm enough for robot cleaners – some need the water to be around 15C.

Read more: Swimming pools: How to check you are within tax rules in France

‘Shock treat’ water

You then need a “shock treatment” of the water using your normal products (chlorine, bromide salts etc.) and then switch the filter on to continual operation for 24 to 48 hours.

At this stage get out the brushes and clean the sides of the pool carefully – using the time to also check there are no cracks to the lining or grouting in tiled pools.

Check and clean the filter every day if needed during this time.

If the water does not clear up, do not panic, keep filtering for up to a week, till you can see the bottom of the pool.

You need also to get out the chemistry set, and check that the PH of the water is between 7.2 and 7.4, adjusting it with pool acid or alkaline if necessary.

For chlorine pools, check that the level is between 1 ppm and 1.5 ppm.

The next check is for the Complete Alkalimetric Titration (TAC in French) which checks the level of bicarbonates and carbonates, which needs to be between 80 ppm and 120ppm, and the TH for the concentration of calcium and magnesium (how “hard” or “soft” the water is), which should be between 150 ppm degrees and 250 ppm.

Where the filter has been left on all winter, the process is usually quicker after the basic cleaning of the pool and its surrounds has been done, because usually, the water chemistry is at or near the recommended levels.

Clean the filter, check the pump does not need to have deposits cleaned, and set the filter to its summer settings, before having a shock treatment and a 24- / 48-hour filter to, hopefully, get crystal clear water.

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