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Plumbing

How Does a Plumber Find a Water Leak Underground?

7 minutes read

Underground water leaks are a homeowner’s nightmare. They are hidden, costly, and potentially destructive. A small leak can waste thousands of gallons of water and cause structural damage if left undetected. 

But how do plumbers locate these invisible leaks without tearing up your yard or driveway? In this guide, we’ll walk through the professional techniques used to detect underground plumbing leaks quickly and efficiently.

Steps for Underground Leak Detection

Step 1: Inspecting Visible Signs

Before breaking out the heavy machinery, a trained plumber starts with a careful visual inspection. Even hidden leaks often leave behind subtle clues that an experienced eye can spot. We look for specific environmental changes around your property, such as:

  • Wet or soggy patches in the yard
  • Unexpected spikes in your water bill
  • Low water pressure throughout the house
  • The sound of running water
  • Cracks in your home’s foundation

If these signs are present but the exact source isn’t obvious, we move on to more technical diagnostic tools to narrow down the search.

Step 2: Pressure Testing

Plumbers can determine if and where a leak is present by isolating the system. By shutting off the water supply and monitoring the system’s pressure levels, we can see if the pipes are holding pressure. A sudden or steady drop signals that water is escaping somewhere underground.

Step 3: Thermal Imaging Cameras

For leaks that are difficult to spot with the naked eye, technology is our best friend. Infrared cameras detect slight temperature variations in the ground, revealing where water may be pooling. Thermal imaging is particularly useful for hot water line leaks, as the heat signature shows up clearly against the cooler surrounding soil.

Step 4: Video Pipe Inspection

To get an inside look at what is happening underground, we use video pipe inspection. A small, waterproof camera is inserted into the plumbing system, providing real-time footage of the pipes’ interior. This method allows us to visually confirm the root cause—whether it is a crack, heavy corrosion, or a blockage causing a pressure buildup and subsequent leak.

Why You Shouldn’t Ignore an Underground Plumbing Leak

It might be tempting to put off a repair if the leak isn’t actively flooding your basement, but underground leaks are silent destroyers. Delaying a repair often turns a minor plumbing issue into a major renovation project. Leaving a leak unchecked can lead to:

  • Structural damage
  • Mold and mildew growth
  • High water bills
  • Sinkholes and soil erosion

Addressing the problem early is always cheaper, safer, and less stressful than dealing with these long-term consequences.

Can You Find an Underground Water Leak Yourself?

While professional tools are best for pinpointing the exact location of a leak to avoid digging up the wrong spot, you can do some preliminary detective work. If you suspect an issue, here are a few simple tests you can run to confirm the problem.

  • Water meter test: 

Turn off all water inside and outside the house. Watch your water meter; if the dial is still moving, water is leaking somewhere.

  • Food coloring test: 

Add a few drops of food dye to your toilet tanks. If the color seeps into the bowl without flushing, you have a leak in the toilet (a common culprit for high bills).

  • Yard inspection: 

Walk your property and look for soggy areas or patches of grass that are unusually green compared to the rest of the lawn.

These tests can verify that a leak exists, but they rarely tell you exactly where to dig. That is where our advanced technology comes in to save the day.

When to Call a Professional for Underground Water Leak Detection

You should reach out to a professional immediately if your DIY checks confirm a leak or if you observe any red flags in your home’s plumbing performance. It is time to call Arnold & Sons Plumbing if you notice:

  • Unexplained water bill increases that don’t match your usage.
  • Persistent low water pressure that doesn’t resolve itself.
  • Wet spots or pooling water in the yard during dry weather.
  • Foundation cracks or shifting ground around your home’s perimeter.
  • Sounds of running water behind walls or under floors when pipes aren’t in use.

Don’t let these symptoms linger. A quick response from our team can save your yard and your foundation from extensive damage.

Underground Water Leak FAQ

How long does it take to detect an underground leak?

Most leaks can be pinpointed within a few hours using specialized equipment.

Will leak detection damage my yard?

No. Non-invasive tools like acoustic sensors and thermal imaging help locate leaks without digging.

Can Arnold & Sons fix the leak once it’s found?

Yes! We provide full-service leak repair to restore your plumbing system quickly.

Schedule Professional Leak Detection Today

Underground water leaks are serious, but finding them doesn’t have to be a guessing game. If you suspect an underground plumbing leak, don’t wait. Contact Arnold & Sons Plumbing today! Our experienced team is ready to help. Call us today or schedule an appointment online.

 

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351 West Hubbard Street Chicago IL 60654 US
309.691.8291
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