Can a Pool Overflow from Rain (Easy Fix) - Globo Pool
Pool Care Pool Troubleshooting

Can a Pool Overflow from Rain (Easy Fix)

A swimming pool gives us a haven from all the scorching heat and a busy week. But at times, Mother Nature disrupts everything. When it rains, you cannot swim, and when the rain is over, you’ll probably have other issues to deal with, one being pool overflow from rain. Is it possible?

Of course, your pool can overflow from rain. If you have never experienced it, some people have. It’s probably the most underrated problem pool owners face. It’s quite a common problem for most people, especially in areas that receive heavy rainfalls and storms.

The fact remains, it’s an avoidable problem with practices starting from construction to simple pool maintenance. In this article, I will take you through easy ways you can fix pool overflow from rain and simple tricks to help you avoid the problem entirely. Read along!

Will my pool overflow from rain?

An average rainfall should be an issue for your swimming pool. That’s because the pool drains and skimmers can handle the additional water. Pool building experts plan for these coping to be around 2-inches below the home’s water level during the construction, safeguarding against flooding.

However, if your area receives heavy rainfall, a tropical storm, or even worse, a hurricane, your swimming pool drain might not help to lead to overflow. The amount of water received during such weather can fill a tank in hours.

Now imagine your pool is almost full and the water keeps draining to it. At a certain point, the runaway water could also get to your swimming pool if the backyard drainage is filled up.

What Happens If a Pool Overflows from Rain?

Average rainfall by itself wouldn’t harm your swimming pool. However, as the raindrops fall, they collect pollen and other particles in the air depositing them into your pool and onto the ground.

Any runoff that finds its way into your pool water will contain contaminants that can turn the beautiful, relaxing oasis into a mess. When the pool fills up and starts to overflow, a lot can happen. Here is a list of misfortunes your pool can endure if it overflows from rain.

Chemical Disruption

Pool chemicals maintain the pool water cleanliness. They are responsible for making sure the water is safe for both the swimmers and the swimming pool itself. And they have to stay balanced for their protection to be adequate.

If the swimming pool were to overflow from rain, the chemical gets diluted, leaving your swimming pool unprotected. At times, if you in a warm climate, this could lead to rapid algae growth, making the swimming pool not swimmable.

That’s why it’d be best to test and balance the water immediately after the storm. You will have to reduce the water to the ideal level and clean it first before testing it.

Water Damage

If you have an above-ground pool, and the water starts to spill from one edge, the chances are, the whole thing will collapse and leave you with an empty swimming pool. There’s also the risk of the walls bending or the liner bursting.

If it’s a semi above-ground pool, the spilling water can wet the grass to the point that it cannot accommodate any excess water. Excessive water can cause several problems, such as pool equipment malfunctioning and deck damage. The equipment such as the pool pump and the heater could get flooded, and the causalities might be extreme.

You might even be forced to buy new ones, especially if they were running when they were flooded. If the water sits under the deck for an extended period, there could be heaving, cracking, or lifting. The problem is common in areas with clay-based soil or an older pool.

When the wet soil expands, it creates an upward force that can elevate the deck. Even though when the water dries up, it can get back to the original, there will still be markings that show the cracking.

Another thing, if you’re pool is near the house, few inches below the house floor, it could mean the rising water might end up entering your home and causing an interior flood.

How Does Pool Overflow Affect Pool Chemistry?

As I mentioned in the section above this, pool overflow from rain disrupts pool chemistry. How?

When the rainwater enters your swimming pool, the water capacity increases but the chemicals you used remain the same. Because of these, they become diluted, affecting the chemical balance.

According to expert, raindrops collects few gases as it falls. Upon reaching the ground, the water is acidic. If it enters your swimming pool in this state, it will disrupt your pool water chemistry.

Plus, rainwater adds pollutants from the air to your pool and brings in contamination you don’t want. And, algae can set in quickly if you don’t act fast. Apart from this, there are pollutants and contaminants the raindrops could carry with them during the fall.

When they enter your pool water, chemical balance will shamble. Algae will take the opportunity to increase their growth, especially if the water remains warm.

How to Drain and Lower Water from Your Pool after Overflow

When your swimming pool overflows from rain, you want to lower the pool water level back and proceed with the next after-rain maintenance steps. Here are the multiple ways you can drain some water from your overflowing swimming pool.

Use the Filter Multiport Valve

What type of pool filter do you have? Sand or DE filter? If so, you’re in luck. The units come with a multiport valve used for or various functions like filter, circulate, drain, rinse, and more.

You can use two settings here (backwash or waste) to drain the water. These settings send the water to a drainage port to redirect it to an ideal draining spot.

The difference between the two is that the backwash setting reverses the filtration flow to help clean the filter, while the waste setting bypasses everything to waste. I would recommend the backwashing method since it’ll help you clean the filter media while draining water from the pool.

Use Pool Pump Drain Plug

If your pool uses a cartridge filter, you cannot use a multiport valve since it doesn’t have one. It does allow you to remove the filter cartridge during cleaning.

You can use the pool pump’s drainage spigot set between the pool pump and the pool filter for such a case. Connect a garden hose to the spigot, open it up, and the system will do the rest.

Siphon the Water

If you have an above-ground pool, there is a cost-free method of draining the excess water, siphoning the water. All you need is a drain hose and fill it with water with one end closed. Drop the open end to the swimming pool, lay down the hose on the draining spot, and allow the water to flow.

Remember, the place you’re draining to must be on lower ground than the swimming pool to allow gravity to do its work. The same method could be used for a semi-raised inground pool.

Use a Submersible Pump or a Cover Pump

Pool owners mostly use a submersible pump, or a cover pump to keep their pool cover dry during winters. It’s also an ideal piece of equipment to get water out of a flooded basement as it works the same as a sump pump.

A submersible pump works underwater. If you have one in your home, you can connect a drain hose and drop it into your swimming pool. Allow it to sink to the pool bottom, direct the drain to an ideal draining spot, and power it on. It’s an ideal option if you don’t have a spigot, a multiport valve, and the siphon method isn’t applicable for you.

Dos and Don’ts When Dealing With Pool Overflow from Rain

  • Before you can start the draining, make sure you know what you’re doing, and also, you have enough time to supervise the whole procedure.
  •  Don’t leave your premises while your pool is still draining. Be available to turn off the pool pump or change the valves when the water reaches the desired level.
  • Ensure you’re draining the water in an approved location. It will help you avoid flooding your neighbor’s lawn or backyard.
  • Never delegate pool draining to a minor or anyone unfamiliar with your pool pump and the valves.
  • Don’t ever operate a piece of electrical equipment while standing in water.

How can you prepare and prevent pool overflow from rain?

Though it can be tough to prevent rainwater from entering your pool, there are ways you can prepare it for the rainfall effect and prevent overflow.

Lower the Pool Water Level

If the weather focuses on new predictions, there will be a heavy storm in your area, reducing the pool water a few inches. That gives it enough space to fill and prevent overflow.

Test and Balance the Water Chemistry

Check the water chemistry of your pool water before it rains. You want to make sure the alkalinity and pH are balanced in the high range, around 7.8. That’s because rainwater is acidic.

If it enters your swimming pool in such a state, it can help balance it to the lower range, around 7.2. You will have to repeat the same process after the rain, but that’s on another section.

Attend to Your Yard Drainage

Poor drainage in your yard can be the culprit of your pool overflow problems. When it rains, does your backyard flood? If so, there’s a problem with your drainage system. Check to make sure it’s not blocked in any way. If no visible signs, the problem might be underground.

It’d be best to call a professional to check it out and repair it in such a situation. It’ll benefit both your home and your swimming pool at the same time.

What to Do After Solving Pool Overflow Problem

After draining the overflowing water and returning the water level to its original level, you have to maintain your pool to make it swimmable again. Here are a series of things you can do to restore your swimming pool.

Skim the water: Use a leaf net to assist the skimmer in removing all the debris that might have entered your pool during the heavy rainfall.

Run the pool filtration system: Running the filtration system will help remove any dirt and other contaminants brought in by the raindrops. If there are strong winds, your pool could have received pollen and dirt, and the filtration can help remove them.

Balance the pool water: Once your swimming pool is clean, you can test your pool water using a pool testing kit or take a sample to the nearest pool store for testing. After getting the test results, balance the pool chemicals right.

Shock your pool: the last bit of making your pool swimmable is to shock it. Pool shocking kills any algae and microorganisms in your pool and prevents algae spores from growing. You can use this opportunity to add an algaecide to add some strength to the algae control.

Add water clarifier: If the water is still cloud even after shocking it, add a pool clarifier. The chemical will help break down the cloudiness.

Final Verdict!

Pool overflow from rain is a common problem, maybe not in your area, but it’s a menace and a nightmare to those living in areas that receive heavy rainfall, storms, and hurricanes. If you want to keep your swimming pool in good condition, it would be best to lower the pool water before a storm, balance the pool chemistry, and do the necessary cleaning and shocking after the rain.

About the author

Sharif Miah

Hi! I'm Sharif, the founder of Globo Pool® and I have been working in the pool & hot tub industry for the last few years. I love to share my experiences with people & hope you are enjoying my information and lessons!

Leave a Comment