April Showers, Bring Concern to Swimming Pools

We have all heard the old adage “April Showers, Bring May Flowers”. Those showers also bring concerns to our swimming pools. When it rains, there are many effects that the rainwater can have on our swimming pools whether they are open or closed. Let’s explore how it can affect our pools.

A Little Water Never Hurt Anyone

When rainwater falls into your pool, it affects your water chemistry. Rain water is going to bring down your chemistry readings. This means your sanitizer will be lowered, as will as your pH and alkalinity. This can all contribute to cloudy water and algae growth. It will also dilute your calcium hardness and cyanuric acid levels. A low calcium hardness level, which can especially affect gunite pools, can lead to the water becoming aggressive and affecting your surface and pool equipment. When your cyanuric acid is lowered, it affects the ability for your sanitizer to be maintained against UV degradation.

Look What the Cat Dragged In

When it rains, the rain brings in our environmental debris including sticks, leaves, acorns, bugs, pollen, pesticides, and dirt. All of these things place a higher demand on your sanitizer making it less effective to oxidize and sanitize. Also, all of these items supply nutrients for algae growth. These items can also clog up your skimmers which can cause your pump to run dry and burn out your pump motor. These items also have the potential to lay on your surface and cause surface staining. After a rain event, you want to get as much debris and contaminants out of the pool as possible to thwart any potential problems.

In the Blink of an Eye

If you are one of the unlucky ones, you may have seen your crystal-clear pool go from blue to green in a snap. An algae problem can sneak up on the best of our pool owners. When it rains, it can bring in increased phosphates and nitrates which algae loves. It can also wash pesticides from your landscaping into your pool which algae also love. All of this can turn your pool green quickly. So, it is best after a rain storm to test your water and balance chemicals as soon as possible.

Saving for a Rainy Day

So, what is a pool to do in case of a rain event? It is best to be proactive rather than reactive. The best thing to do is to keep properly maintained water chemistry. Shocking prior to a rain storm will help to maintain your sanitizer and may prevent against algae growth. It is recommended to keep the pH and alkalinity at the higher end of the ideal range so when the rain comes it hopefully will bring it down only to the lower end of the ideal range. If we are expecting a severe storm, you can consider taking extreme proactive measures like lowering your water level an inch or two to accommodate against increased water getting into the pool from the rain. For more tips and tricks, give us a call…. before the rain comes.

*This information is obtained from the Certified Pool and Spa Operator Handbook. This information may not be applicable to your pool based on your pool type and location. One should reference all applicable regulations and standards for your facility.

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