How to Safely Drain an Inground Pool

As a pool owner, you’re probably aware that draining your inground pool is not ideal. Once you’ve drained it you will need to refill it and that is not a cheap procedure. However, chances are you bought your pool because you enjoy a refreshing, clean swim, not because you wanted your own home skate park, so draining your pool is unavoidable

The time to drain will come, especially if you’ve had your pool for a while. Luckily this isn’t a weekly, monthly, or even yearly process. Your pool will need draining every few years, but when it does happen, it needs to be done correctly. If not, you could seriously ruin your inground pool.

I’m going to explain when your pool needs to be drained, how to do it, and also how to refill your pool afterward. Time is of the essence, so let’s get started right away.

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Why drain your pool?

As draining your pool is a procedure that only needs to be done every few years, there are only a few reasons why it needs to happen. If the examples below don’t apply to you, then I would think twice about whether it is really a necessary task right now. I’m trying to help you avoid wasting time, and also to cut costs, so this situation is an ideal example.

To reset the water

Maybe your water’s chemical balance is so off that you’ve decided to get rid of it all and start again. This makes sense and is something that happens to every pool owner. Your water has been sitting in your pool for a long time, but remember that’s why we add chemical sanitizers like chlorine.

There is, however, one element to consider which cannot be removed with any additions to your pool—the remnants of chemicals combined with other dirt, debris, and contaminants. These are referred to as the total dissolved solids (TDS). After building up for a long period of time, they can seriously interfere with the chemical balance of your water. You can use a digital meter or test strips to monitor your TDS. Once it gives a reading of around 2,5000 parts per million (ppm), it is time to drain the pool and give it a fresh start.

In order to reach an ideal chemical balance, you need optimal circulation in your pool. The 1.5 HP Variable Speed Blue Torrent Thunder In-Ground Swimming Pool Pump is a great pump and will save you so much energy in under a year that it pays for itself. It is also eligible for rebates and comes with a lifetime warranty. One customer, Eric D, said, “Day one, I fired this pump up and it ran clean and fast.”

For pool maintenance

Most of the routine pool maintenance carried out can be done with water in the pool. If a high-performance robotic pool cleaner couldn’t function after coming into contact with water that would be quite unreasonable. However, some maintenance jobs really require an empty pool, such as deep cleaning metal stains and calcium deposits, repairing a cracked pool floor, or repainting the bottom of your pool. These jobs come up and they need to be done. If you think your pool will need draining then keep reading.

When to drain your pool: A five-step checklist

I will first tell you the golden rule when it comes to draining your pool—make it quick! Your pool should not be left sitting empty for a long time. How long is too long? I would say more than one week. Look at the checklist below and follow it to make sure you’re not out of your depth when you start draining your pool.

  1. You’re ready to pay the bill

I hate to tell you this, but it isn’t going to be a cheap job. You’re going to be draining and replacing up to 20,000 gallons of water! Make sure you’ve budgeted ahead for next month’s water bill.

  1. You have the time

Remember, you don’t want your pool to be left empty for more than a week at the most. You will also need to allocate time during the draining process. You don’t want to have other jobs to do while you’re dealing with moving thousands of gallons of water. At a guess, I would say it will take between eight and sixteen hours to completely drain. And refilling it afterward? That takes just as long I’m afraid.

  1. It’s a sunny day, but not a scorcher

For obvious reasons, you don’t want to do this job when it is raining, but just because it is a sunny day doesn’t mean you’re good to go. The heat from the sun can badly damage your pool. If you drain it during a heatwave you can be sure to see all sorts of damage from cracked pool walls and floors, to pool liner damage. Never leave an empty pool sitting in temperatures of 85 degrees Fahrenheit/29 degrees Celsius or above.

  1. Your chemical levels are already down

You can take a break from treating your water now. I bet you never thought you’d hear that! The truth is, your city probably requires that your pool water doesn’t have high concentrations of pool chemicals when you drain it. Make sure you use test strips before draining to check that your water’s chlorine is pH neutral, and there are no traces of other chemicals. To find out the exact levels and regulations, contact your local water authority.

  1. Your circulation system is already prepped

Time to turn the automatic timers off. Just imagine, your pump decides to turn on at some point during the draining process. It pulls in air instead of water, overheats, and potentially melts the pump. No, thank you. Or imagine the pool lights come on at 7:00 but the pool is empty so they heat up and shatter. Enough imagining. Go and turn your systems off—go!

Once your pool has drained, you might discover that it wasn’t as clean you had thought. To get your pool floors and walls sparkling again, without injuring yourself, we recommend the 360-Degree Bristles Black & Decker Pool Brush. To prevent back pain and hip problems that one-sided brushes cause, this brush was designed by pool professionals.

Avoid the inground pool popseriously!

It is tempting to skip past the precautions and get straight to the “how to” part. What could go wrong? Well, quite a lot actually. A pool pop up is probably the worst thing that could happen. Just as it sounds, this is when the floor of the pool floats (pops) up. Also, the PVC pipes beneath the floor crack or come apart, and the shell of the pool also cracks. The top edge of the pool will then crack or fall apart, there will be damage to the concrete surrounding the pool, and the electric wiring for the pool lights will be ruined which in turn causes a high risk of electrocution. Yes, you read that right, electrocution. What about homeowners insurance you ask? It rarely covers the damage.

We really do not want this to happen to your pool. To be safe and avoid your pool popping up, we recommend you hire a professional. This applies to you especially if your pool is at high risk, for example, if you live in a high water table area. This is when water only soaks into a slight layer of the ground rather than travelling down further. Also at risk are those who have had rain recently. If your pool is not at risk then the tips below should help avoid any disasters.

Know where you’re going to drain

Before you start the drainage, you will need to have a game plan ready. Remember that you’re about to move thousands of gallons of water. It all has to go somewhere and your yard is not one of the options. Firstly, you don’t want water filled with chemicals going on your grass, and secondly, your pool is more likely to pop up when there is pressure around your pool under the ground. Putting drained water around your pool is going to lead to regrets.

So where should all the water go? Just like with the chemical levels, you should consult your local water authority for their regulations. Usually, the water needs to be directed into a sewer line or cleanout, but in some areas you can drain pool water directly into public lines in the street. Some cities also have restrictions about when you can drain your pool, so check out the regulations that apply to you.

You want to be extra cautious in order to avoid any popping up of the pool. Ensure you have a sufficiently long hose for drainage that will reach wherever you are draining your water. Direct the hose downhill from the pool to avoid any other drainage issues. You don’t know your sewer cleanout is clogged until you try and push thousands of gallons of water through it. If water starts to come back toward you, you will want to make sure it is going nowhere near your pool.

Remember that your pool pump is the heart of your circulation system. Having the right one will not only prevent you from needing to drain anytime soon but also help cut down costs. The Blue Torrent 2 HP Variable-Speed Pump is ultra-powerful and comes with a lifetime warranty. It pays for itself in months with the energy it saves, and you can get a rebate on this pump. As one customer, Bill Britton, said, “Runs great. Super quiet.”

If there’s been rain, wait

Had a stormy week? Well, if you were ever wondering when the worst possible time for pool draining was, then this is it. The rain that has sunk into your yard created more pressure on the sides of your pool which increases the risk of a pool pop as the water from the pool is emptied.

Wait a few weeks and let the ground dry out completely before you attempt to drain the pool. The ground may look dry but you don’t know what is happening underneath. A pool pop up is one extreme way to find out.

Understanding how to relieve your valves

Time for some technical vocabulary. Your pool’s hydrostatic pressure relief valves are a key feature to preventing a pool pop up. If this is the first time you are draining your pool you may not even know that you have them.

When you look at your pool’s floor, you should see one or more rings plastered in place. Underneath the plastic, they are threaded into a slotted pipe that runs along the floor of the pool and ends in a gravel pit that was placed underground when the pool was originally built.

Through these valves, any water that has accumulated underground can come up to the pool when it is drained. Without them, the water collected underground would create enough pressure to cause your pool to pop.

Once the pool has mostly drained, you can remove the rings to reduce the pressure. It would be useful to have a few extra ready just in case they get damaged during removal. It is always best to be prepared when you’re draining your pool.

Ready? Let’s get draining in five steps

You’re aware of the dangers and know how to avoid them, so now it is time to seal the deal—hopefully without unsealing your pool’s floors and walls. These instructions will make draining as safe as can be.

  1. Swap you regular pump for a submersible pump

Your regular pool pump is not going to cut it. It is only designed to suck in water, so once your pool starts draining, the pump will be sucking in air which can lead to a whole host of permanent damages. That’s why it is best to rent or buy a submersible pump. These are not cheap not they won’t break the bank either.

Make sure your power cord reaches the bottom of your pool from the outlet and place the submersible pump on the pool floor in the center of the deep end. Avoid using an extension cord for this. The pump will have a hose connected and you need to place the other end of the hose wherever the drained water is going. Ensure that it reaches all the way or you will have thousands of gallons of escaped water to deal with.

  1. The moment we’ve been waiting for: Start draining!

Simply turn on the pump and drain away. Even if it takes a long time, you need to stay and watch the hose and cords. Make sure everything is running smoothly so you don’t have any house floods to deal with.

While your pool is draining you can get on with another task. Switch over to saltwater so your chlorine is operating at the lowest, safest, and most consistent levels possible. You can make a smooth transition with Salt Ways Eco-Friendly Salt Chlorine Generator which is a trusty option with an added lifetime warranty.

  1. Say thank you and goodbye to your pump

There will come a point when the water level will be so low that the pump no longer is pushing anything out of the pool. This is totally normal, and it is very rare that you need to drain every last inch of water. Anything left behind won’t mess with your pool’s chemical balance in the future. You can turn off and remove the submersible pump now as it is time for the next step.

  1. Time to open the flood gates – or just your relief valves

To keep your pool from popping up you will need to ease the pressure of the underground water by opening the hydrostatic pressure relief valves.

  1. Do what you need to do

If your reason for draining the pool was to fix the chemical balance, then you should proceed to the next steps immediately. If you have work to do to your pool (e.g. repairing or painting) you can go ahead and do that now. In the rare case that you need the floor to be completely dry in order to work, use a heavy-duty and durable cover pump such as the Brute Force Pool Cover Pump. As soon as you can, no later than one week from draining, proceed to the next steps to refill your pool.

How to refill your pool in three steps

A pool is supposed to be full of water so let’s get it back to how it should be. The refilling process is a lot simpler than the draining part but it will still take time. You will also need to rebalance your water from scratch. It will all be worth it once you are swimming in your pool again.

  1. Replace the relief valves

Go and restore the relief valves. You don’t want them opening when you refill your pool with water. That will drown out the gravel pitch, creating immense pressure. Tightly twist the plug into the valve using Teflon tape on the threads.

  1. Refill your pool and turn on the pump

Using as many garden hoses as you have, refill your pool. If your water source is highly concentrated with metals, you should put hose filters on if not you will have unsightly metal stains later on. That would mean draining your pool again. No, thank you.

  1. Balance your water

Just as you do when opening your pool for swimming season, you need to balance your water from scratch. This is the hardest part of the refilling process, but you will be rewarded with clean, sparkling, and safe water very soon.

That must’ve been draining!

Although the physical aspects of draining a pool are not too strenuous, the planning, waiting, and extra waiting, can be really exhausting. Now that your water is balanced, you can dive back into your pool and relax. Order has been restored and everything is as it should be. Enjoy!

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