Swimming pool leaks can be frustrating, especially when the water level keeps dropping despite regular maintenance. Homeowners often wonder: can you fix a pool leak underwater? The answer is yes — many types of pool leaks can be fixed without draining your pool. This is great news for anyone wanting to save time, water, and effort while protecting their pool investment.

At Showtime Pools, we specialize in pool leak detection and repair throughout Toronto, the GTA, York Region, Durham Region, Simcoe County, Peel Region, and Muskoka. Our expert team uses advanced technology and proven methods to accurately locate and fix leaks — even when they are underwater.

In this blog, we will explain how underwater pool leak repairs work, what tools are used, and why early detection is essential. By the end of this post, you will clearly understand what underwater repairs involve and why addressing leaks quickly is so important.

What Causes Pool Leaks?

Before answering “can you fix a pool leak underwater?”, it helps to understand where and why leaks occur.

Here are some of the most common causes:

• Cracked pool surfaces (tiles, plaster, concrete, or vinyl liners)

• Faulty fittings such as return jets, drains, and skimmer boxes

• Underground plumbing leaks

• Separated expansion joints or structural cracks

• Worn-out gaskets and seals

According to industry research, up to 30 percent of residential pools will experience a leak at some point. If ignored, a leak as small as 1/8 inch per day can lead to a loss of over 700 gallons of water per week in an average-sized pool.

How Do You Detect a Pool Leak?

Leak detection is a precise science that relies on both visual inspection and modern diagnostic tools. At Showtime Pools, we use non-invasive equipment such as:

• Electronic leak detection probes

• Pressure testing systems for plumbing lines

• Underwater microphones (hydrophones)

• Dye testing for confirming surface leaks

• Thermal imaging for temperature variation around the leak site

Our trained technicians perform a full inspection of both the pool structure and underground plumbing. In most cases, the source of the leak is found within 2 to 3 hours, depending on the pool size and construction type.

The most common signs of a leak include:

• Water loss exceeding normal evaporation (more than 1/4 inch per day)

• Wet or soggy spots around the pool

• Air bubbles in return lines

• Loose tiles or cracks

• Increased water bills

Once the leak is located, the next step is determining the best method for repair — and often that means fixing it underwater.

Can You Fix a Pool Leak Underwater?

Yes, you can fix a pool leak underwater, and it is a standard practice in professional pool maintenance. In fact, draining a pool can sometimes do more harm than good, especially for in-ground pools in the Toronto and GTA climate. When a pool is emptied, the surrounding soil pressure can cause structural damage, particularly if the groundwater table is high.

Fixing leaks underwater is safer for the pool structure, and more efficient in terms of time and water usage.

Here are the most common underwater repair techniques:

1. Underwater Epoxy Putty or Sealant

This is used for cracks in concrete, gunite, or fiberglass pools. The epoxy hardens quickly and bonds with wet surfaces. Repairs can be completed in under 30 minutes, and full curing occurs within 24 to 48 hours.

2. Vinyl Liner Patch Kits

For vinyl pools, adhesive patches are applied directly underwater to seal tears or holes. These patches are pressure-resistant and can last for years when applied correctly.

3. Skimmer and Fitting Repairs

Leaky skimmer throats or return lines can be sealed with specialty underwater products, sometimes combined with hydraulic cement for added strength.

4. Leak Repair In Pool Lights or Drains

If the leak originates around light fixtures or bottom drains, a flexible sealant is injected around the perimeter to stop water loss without removing fixtures.

5. Plumbing Leaks Repaired from Inside Pool

When underground pipes are leaking, some advanced solutions allow internal repairs using inflatable pipe plugs and epoxy injection through pool fittings — all done from within the pool.

Each method is tailored to the specific type and location of the leak. At Showtime Pools, we conduct a detailed evaluation before deciding on the most effective underwater repair.

Why Fixing a Pool Leak Quickly Matters

Delaying repairs can result in:

• Structural damage to the pool shell

• Erosion under the pool foundation

• Chemical imbalance due to constant water replacement

• Increased utility bills

• Damage to landscaping and nearby structures

A leak that goes unchecked for just one month could lead to the loss of over 25,000 liters of water — that’s equivalent to over 150 bathtubs full of water. This water loss also includes your pool’s chemicals, which means more frequent chemical balancing and potential algae outbreaks.

That’s why we always recommend early intervention. Our professional leak detection and repair team can identify and fix a pool leak underwater quickly and effectively — saving both your water and your wallet.

How Long Does Underwater Leak Repair Last?

When done professionally, underwater leak repairs can last for 5 to 10 years, depending on the material used and the pool condition. Epoxy seals, vinyl patches, and flexible underwater caulks are designed to withstand water pressure, chemical exposure, and temperature changes.

We often revisit older pools in the Durham Region, York Region, and Simcoe County, where original repairs made years ago are still holding strong. This proves that with the right tools, experience, and technique, underwater repairs are a long-term solution — not just a temporary fix.

What Types of Pools Can Be Repaired Underwater?

Underwater repairs are possible on virtually all pool types:

• Concrete and Gunite Pools: Sealing surface cracks or tile joints

• Vinyl Liner Pools: Applying underwater patches or replacing gaskets

• Fiberglass Pools: Fixing spider cracks or leaks around returns

Our service areas cover everything from backyard pools in Toronto to high-end resort-style pools in Muskoka. Wherever your pool is located, our mobile leak detection unit is ready to help.

How Showtime Pools Makes a Difference

At Showtime Pools, our mission is to take the stress out of leak detection and repair. We serve homeowners and commercial pool operators across Toronto, GTA, York Region, Durham Region, Simcoe County, Peel Region, and Muskoka.

Here’s what sets us apart:

• Fully equipped mobile units

• Same-day appointments available in peak season

• Non-destructive detection tools

• Over 15 years of combined experience

• Clear communication and detailed reports

When you ask, can you fix a pool leak underwater? — we don’t just say yes. We show up with the right tools, perform a precise diagnosis, and apply durable, proven repair techniques that stand the test of time.

Final Thoughts: Can You Fix a Pool Leak Underwater?

Let’s repeat it loud and clear: Yes, you can fix a pool leak underwater. Whether it’s a cracked surface, leaking skimmer, or damaged light fixture, modern repair methods allow you to resolve the issue without draining your pool or causing more problems.

A small leak may seem harmless, but the long-term consequences can be costly. Fixing your pool underwater ensures that your structure stays strong, your water stays balanced, and your peace of mind stays intact.

If you suspect a leak or notice your water level dropping, don’t wait. Showtime Pools is just a call away. We provide expert pool leak detection and repair with services available across Toronto, Durham, York, Peel, Simcoe, and Muskoka.

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Contact Us Today
Showtime Pools
(289) 264-1250
info@poolleakdetection.com
www.PoolLeakDetection.com