Do you have too much water in your pool due to rain? Is your inground or above-ground pool overflowing?
Whether it’s torrential rain or a light shower, rainwater going into your swimming pool can be problematic (and even expensive) if left unchecked — especially if it causes your pool to overflow.
This will article will explain why rainwater can be bad for your pool, and how to go about draining and rebalancing the water the right way.
What Happens When a Pool Overflows from Rain?
How bad can excess water really be in a swimming pool? Well, as it turns out, things can get pretty bad, especially when we’re talking about rainwater.
It Compromises Your Filter System
Water doesn’t necessarily need to be flowing over the edges of your pool for it to have too much water in it.
The optimal water level for most inground pools is at around the midpoint of the skimmer opening, so anything over that level could be considered “overflowing”.
When that happens, the skimmers won’t be able to absorb surface debris, which means the filtration system ends up being compromised. Eventually, things like leaves, bugs, and other debris build-up and your water becomes murky.
Note: If your pool is only marginally over the ideal water level, letting the water evaporate over a few days might be all it takes to solve the problem.
It Messes With Your Pool Chemistry
Rainwater isn’t like the water in your pool.
First of all, rain is acidic so it will cause your pool water pH level to become more acidic. This not only inhibits sanitation and potentially leads to stains on your pool, but it can also cause discomfort to swimmers.
Secondly, it doesn’t have the necessary chemicals to maintain clean and clear water. It contains zero chlorine or any other sanitizing agent, no pool stabilizer, and almost no calcium.
Thirdly, as rain falls through the air, it picks up all sorts of contaminants along the way such as dust, spores, and other particles. When that rain enters your pool, those contaminants consume even more chlorine.
For all the additional water in your pool due to rain, you’ll need to counteract that by readjusting the pH and adding a slew of chemicals to rebalance the pool chemistry.
It Floods the Surrounding Area
The water has to go somewhere, right?
That somewhere is likely going to be the immediate surrounding area, and ultimately the rest of your backyard.
Without proper drainage, large amounts of water spilling out of your pool can lead to flooding. This not only destroys the landscape but also creates a soft, wet environment that attracts all kinds of insects, including mosquitos.
In severe cases, too much moisture in the surrounding soil can even cause your swimming pool shell to completely pop out of the ground when drained; a phenomenon known as “pool popping”.
If this is a recurring problem, your pool deck, coping, and caulking will also be at a higher risk of staining, cracking, or worse damage due to excessive exposure to water.
It Damages the Pool Itself
It’s hard to imagine that too much water can cause damage to a pool, but it’s not as farfetched as you hoped.
If you have an inground pool that’s overflowing, it’s possible some water can find its way between the pool wall and vinyl liner, which may eventually lead to sinking on the affected side.
If you have an above-ground pool that’s overflowing, the primary concern should be your pool walls and frame having to withstand more pressure than they were designed to.
If that wasn’t bad enough, your pool equipment isn’t safe either. One of the more common issues to watch out for is flooding your pool pump, which can lead to short-circuiting and sometimes even permanent damage.
How to Drain Your Pool After Rain (When It’s Overflowing)
Before draining your pool, it’s important to think about where you’re putting the excess water. Be sure to check your city regulations for water drainage before expelling a large amount of water.
Now, let’s cover your best options for lowering the water for both inground and above-ground pools.
Use a Garden Hose
If you have a standard garden hose, you can siphon the water out of your pool without requiring any other equipment.
- Simply place one end of the hose into your pool and screw the other end onto your outdoor tap (spigot).
- Turn the water on and wait for the water to fully pass through the hose, pushing out all the air.
- Finally, turn off the water, unscrew the hose from the tap, and set that end of the hose down wherever you wish to drain the water.
If done correctly, you should start seeing the water from your swimming pool being “sucked” out through the hose.
Use Your Drainage Spigot
This is similar as it requires a garden hose to drain the water, however, it also relies on a particular feature of your plumbing.
Some filter systems allow you to attach a hose spigot directly to the plumbing. If you’re lucky enough to have this option, you can simply attach the spigot and hose in order to suck the water right out of your pools’ circulation.
This is easier than putting the hose directly into your pool because you don’t have to worry about pushing the air out first.
Use a Submersible Pump
If you’ve ever used a pool cover pump to drain water from your cover, you’ll know how submersible pumps work.
These can be good in a pinch as they can be placed directly beneath the water surface, while the attachment hose can be directed away from the pool with pretty high precision.
The downside? Well, they’re not exactly the cheapest thing to buy, so it’s hard to justify a one-off emergency.
Use a Bucket
If your above-ground pool is overflowing from rain, you can often get by just using a bucket to scoop the water out — especially if it’s a small pool such as an Intex or Bestway setup.
The only problem with this approach is that it encourages you to dump the water in the nearby surrounding area in order to speed up the process, but that shouldn’t be an issue for a small volume of water.
Call in a Professional
If you have the time, energy, and equipment to deal with an overflowing pool, by all means, drain it yourself. Otherwise, don’t put your swimming pool and yard at risk over a few bucks.
Most local pool stores should be able to help you out, if not point you in the right direction for something like this.
What to Do After Draining Your Pool
Simply removing the excess water from your pool isn’t enough because you can’t drain the rainwater without also draining some of your original pool water; it’s all mixed together.
For that reason, the last thing you need to do is shock, test, and rebalance your water to bring everything back into harmony.
Shocking your pool is basically like dropping a sanitation carpet bomb. It destroys all the contaminants brought (or caused by) rainwater and allows you to “reset” your chemistry.
Following a successful shock, you’ll need to test your water to figure out what chemicals need to be added. This can be done using a pool testing kit, though choosing the right kit is important for accuracy.
Finally, use those results to add whatever chemicals are necessary to bring the water back into balance. For example, if your pH has dropped a few points, you’ll need to add some soda ash (or baking soda if alkalinity is even lower) to bring it back up to the desired level.
Note: We have a whole guide on how to balance your pool water.
How to Prevent Pool Overflow
Prevention is always the best solution. While you can’t prevent rain itself, there are some things you can do to mitigate the damaging effects on your pool.
Use a Pool Cover
You don’t need to whip out your pool cover every time it rains, as a little rainwater isn’t going to have much impact. However, it’s certainly not a bad idea if you’re expecting heavy or prolonged rain.
Just be sure to use the appropriate type of cover, like a winter cover, as not all of them will do a good job of keeping the rain out.
If rainwater is an ongoing issue, you might consider going the extra mile and investing in a pool enclosure instead.
Install a Drainage System
A drainage system is designed to help water flow away from your pool in a controlled manner.
This not only helps with overflowing water, it helps to mitigate the buildup of rainwater, protects your deck and coping from flooding, and minimizes the amount of slip around the pool to prevent accidents.
Deck drainage can come in various forms, including strip drains, spot drains, and french drains. Each have their pros and cons, so it’s worth reading up on pool deck drains before deciding which one to implement.
Pre-Drain the Pool
If you’re expecting storms or heavy rain, it may be worth proactively lowering the water level in your pool to offset what’s to come.
This proactive approach is ideal if you don’t already have a drainage system installed or pool cover handy to mitigate the impact.
An overflowing pool shouldn’t cost you an arm and a leg, as long as you take quick action to bring the water level back down and rebalance your water.
Besides that, investing some time into overflow prevention will ensure you never have to worry about this problem again.