Quick Summary
- Concrete pools develop three main types of leaks: structural (cracks in the shell), fitting (around skimmers, lights, and jets), and plumbing (underground pipe failures)
- Common causes include shifting soil, freeze/thaw cycles, corrosion, and improper installation
- Key warning signs: needing to add water frequently, mushy ground around the pool, algae returning quickly after treatment, or an automatic filler constantly running
- Small fitting and skimmer leaks can be temporarily patched with silicone, but most repairs require a qualified pool professional
- Plumbing leaks are the most costly, they can require digging up the foundation and replacing pipes
- Prevention comes down to proper installation: pressure-tested plumbing, secured fittings, and professional engineering from the start
Dread washes over you like the water that used to be in your pool the moment you realize there might be a leak. Is there a leak? How did it happen? When did it happen? And the scariest question, how much will it cost to repair it?
This is a common problem that plagues many concrete pool owners. Leak repairs can cost hundreds to thousands of dollars, so it’s important to know the details associated with them.
After more than 25 years in the pool industry, I’ve seen how stressful and expensive concrete pool leaks can become for homeowners. Let’s take a look at what causes them, how leak detection works, and what repair options are available.
Types of Leaks That Require Concrete Pool Repair
Concrete pools are made to last decades, and with good care and maintenance, they can. However, over time, leaks can develop due to age, movement, improper installation, or wear and tear. The three most common types of leaks include:
- Structural leaks
- Fitting leaks
- Plumbing leaks
Structural Leaks in Concrete Pools
A structural leak is a leak in the structure of the vessel itself. For concrete pools, this most likely means there is a crack or fissure somewhere in the pool shell.
Structural cracks are one of the more serious concrete pool repair issues because they can grow over time and lead to larger problems if they aren’t addressed.
What Causes Structural Pool Leaks?
Structural leaks are commonly caused by:
- Poor construction or engineering
- Ground movement
- Pressure from groundwater
- Settling due to shifting soil
- Freezing and thawing cycles
Read Next: Concrete Pool Repair: Structural Problems
Fitting Leaks in Concrete Pools
A fitting leak occurs around penetrations in the pool shell, such as lights, skimmers, jets, drains and railings. Because concrete pools themselves are not naturally watertight, the opportunity for leaks is higher.
What Causes Fitting Leaks?
The cavity of a concrete pool is mainly plumbing, and when a fitting is inserted, builders seal those areas with plaster. Over time, those connection points can become vulnerable to leaks.
Common causes of fitting leaks include:
- Loose or aging fittings
- Cracked plaster around fittings
- Areas around fittings becoming loose or deteriorated
- Movement around installed components
- Improper sealing during installation
Plumbing Leaks in Concrete Pools
Plumbing in a pool can be fickle. Correct installation is critical because if it moves at all, it can leak. This means that the plumbing needs to be secured during installation. If it’s held down with straps or run all the way to the ground, you can rest easy that your plumbing will not move.
What Causes Plumbing Leaks?
Plumbing leaks are commonly caused by:
- Movement of underground plumbing lines
- Settling soil
- Corrosion
- Improper installation
- Plumbing that was not properly secured during construction
Proper installation is especially important because pool plumbing should remain stable and supported throughout the life of the pool.
Identifying a Pool Leak
The process of concrete pool leak detection can be fairly transparent if you know what to look for. You may have a pool leak if you notice any of the following:
- Cracks or gaps in the concrete pool shell
- Settling of the pool into the ground
- Displaced or loose tiles
- Mushy spots or standing water around the pool
- Needing to add water more often than usual
- A sudden increase in your water or electric bill
- Algae forming quickly after a chemical treatment
- The automatic filler constantly releasing water
Early leak detection can help reduce the cost and complexity of concrete pool repair by preventing additional damage to the structure or plumbing system.
Hacks for Identifying a Pool Leak
If you suspect your pool is leaking, there are a few simple tests homeowners can use to help confirm the problem and narrow down the location of the leak.
- Use Food Coloring: If you know you have a leak but want to be sure of the location, grab some food coloring and squeeze it near the cracked area. If there is a leak, you’ll likely see the food coloring get pulled toward the leaking area.
- The Bucket Method: Place a 5-gallon bucket on the second step of your pool. Fill it to match the water level in your pool. Turn off the pump and check the levels in 24 hours. If the water in the bucket is higher than the water surrounding it, you probably have a leak.
Once you’ve determined that you have a leak, the next step is to repair it.
Repairing Concrete Pool Leaks
Concrete pool repair for leaks can range from simple temporary fixes to extensive structural or plumbing repairs depending on the severity and location of the issue.
While some small repairs may temporarily slow a leak, we strongly recommend contacting a qualified pool professional as soon as possible.
- Fittings Leaks: To repair a leak near the faceplate, jets, or lights, you can likely put silicone around it to secure the water and stop the leak.
- Plumbing Leaks: If you think there is a leak in your plumbing, call a professional. It could involve digging up the foundation around the pool and/or replacing pipes. This would be one of those scarier leaks that will likely cost more to repair.
- Main Drain Leaks: Unfortunately, the only option to repair the main drain is to replace it. While you wait for the replacement, you can plug a pipe into the drain and turn it off completely.
- Skimmer Leaks: A temporary fix for a leak in the skimmer is to patch it with silicone. Most cases require a skimmer replacement as a permanent fix.
Preventing Concrete Pool Leaks
When it comes to preventing concrete pool leaks, the secret is in the installation. Concrete pools are made to withstand years of use if installed correctly.
To help reduce the risk of future concrete pool repair, make sure:
- Plumbing lines are pressure tested and securely supported
- Fittings are properly sealed and installed
- The pool is engineered by professionals with the foundation and soil of your property taken into account
Final Thoughts
Concrete pool leaks are fairly common over the life of a pool, but the type of leak and the cause behind it can have a major impact on the repair process. Some issues may require a simple fix, while others can involve more extensive concrete pool repair.
The key is understanding what signs to look for and addressing potential problems before they lead to larger structural or plumbing-related damage. With the right inspection and repair approach, many concrete pool leaks can be identified and repaired before they become even more costly and disruptive.
Frequently Asked Questions
What are the different types of concrete pool leaks?
The three most common types of concrete pool leaks are structural leaks, fitting leaks, and plumbing leaks. Structural leaks involve cracks in the pool shell, fitting leaks occur around components like skimmers or lights, and plumbing leaks happen within the underground plumbing system connected to the pool.
What causes leaks in concrete pools?
Concrete pool leaks are commonly caused by structural cracks, shifting soil, plumbing movement, corrosion, improper installation, or deterioration around fittings like skimmers and returns.
How do I know if my concrete pool is leaking?
Common signs of a pool leak include cracks in the pool shell, loose tiles, wet spots around the pool, constantly needing to add water, algae growth, or an automatic filler that frequently runs.
Can I fix a concrete pool leak myself?
Some small leaks around fittings or skimmers may be temporarily patched using pool sealants or silicone. However, most concrete pool repair work should be handled by a qualified pool professional to properly identify and fix the underlying issue.
From the Author
Concrete pool leaks are one of those issues many homeowners don’t think about until they suddenly start losing water. I’m Jason Hughes, a partner at River Pools Virginia and a fiberglass pool installer with more than 25 years of hands-on experience in the swimming pool industry.
I wrote this article to help homeowners better understand the common causes of concrete pool leaks, what warning signs to look for, and the types of repair solutions that may be involved.
My goal is to give you clear, practical information so you can feel more informed and confident if you ever find yourself dealing with a leaking concrete pool.
From the Manufacturer
At River Pools, we understand that pool ownership comes with ongoing maintenance and occasional repairs, especially as pools age over time. Homeowners dealing with a leaking concrete pool are often trying to understand not only what caused the problem, but also what repair options may be involved and how serious the issue might be.
That’s why we create educational resources like this: to help homeowners better understand common pool problems and feel more informed as they evaluate repair solutions and long-term pool ownership decisions.
If you’re unsure about a concrete pool for your yard, and want to explore how fiberglass pools compare, connecting with a trusted independent installer in your area can help you better understand your options.
Ready to start the conversation?
